* [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series
@ 2010-01-14 14:58 Jason Wessel
2010-01-14 14:58 ` [PATCH 01/40] softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume Jason Wessel
` (40 more replies)
0 siblings, 41 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:58 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo
This is version 2 of the series posted in December.
Thank you very much to everyone who provided feedback on the original
patch set.
The new patch set is more stable, cleaned up based on feedback and now
includes documentation.
The following is a list of differences between since the last time the
kdb / kgdb series was posted:
* All the code is now in linux-next via kgdb-next
* 6 different build breakages were repaired around different .config
options not compiling
* kms / kdb / kgdb was built tested as kernel modules
* The kdb core was split into 2 patches, 1 for the core, and one for all
the files touched outside the kdb core
* kdb_seq_printf added to eliminate the duplicate meminfo commands in procfs
* kdb breakpoint code refactored to remove unused globals and struct members
* Fixed the possibility to loop infinitely in the kdb md command
* Cleaned up the kdb kernel/modules.c patch
* Removed the unused kdb report helper function in kernel/sched.c
* HW instruction and data access breakpoints implementation completed
* The kdb keyboard code no longer modifies include/linux/keyboard.h
* The kernel_probe_read and kernel_probe_write were cleaned up for blackfin
* The blackfin arch specific kgdb implementation was cleaned up and merged
* The debug core now turns off tracing while the kernel debugger is active
* New in the series is a command for kdb called ftdump, which allows
dumping the ftrace buffer
* kdb will automatically set the correct number of rows on the display
via the information from the vt_console when using kms
* There is preliminary documentation for kdb and kms
* The drm hacks patch is still a hack, but cleaned up and using macros
The acks were added for the blackfin, sparc and sh arch specific code by the
respective maintainers.
-- From v1 patch set --
Back in May 2009 an initial kdb prototype was posted to lkml as an RFC
to see if there was sufficient interest to merge kdb and kgdb together.
There was enough interest to continue on with the project, and it is
now in a state where further work can occur to review, and hopefully
merge the code into a future kernel.
If this is the first time you have heard about kgdb or kdb, you might
consider taking a look at the presentation slides from LPC 2009.
http://kgdb.wiki.kernel.org/index.php/Main_Page#Linux_Plumbers_Conference_presentation_2009
The code included in this series does not include any of the USB code
referenced in the presentation.
Several changes have occurred since the original prototype was posted.
All of the architectures using the kgdb core today have had the
functions implemented to make use of the kdb shell. This list
includes x86, arm, ppc, mips, sh, sparc, and blackfin. The proposed
atomic kernel modesetting project now has an initial implementation
for the intel i915 driver, and it should be possible to add atomic
mode setting hooks for any other video driver which makes use of
builtin kernel mode setting. All the dead code and functions that
were not previously implemented in the RFC have been removed or
implemented.
The directory of the kernel debugger changed as well. All the kernel
debugger pieces, the debug core, gdbstub and kdb now live under
kernel/debug.
While the patch set may be slightly large, it is broken down into
logical, incremental functionality. Only the first 12 patches are
needed to see kdb in action on a serial port which has a kgdboc driver
for example.
It is important to understand that this work was directly derived from
the original kdb, and the intent is to deprecate the out of tree kdb
and move all its functionality to this code base. This version of kdb
is completely wired into the debug core and the kgdboc polled I/O
model using the same API used by the gdbstub (which people call kgdb).
The kdb front end in this patch series works a little differently than
if you were to take the original kdb patch set from:
ftp://oss.sgi.com/projects/kdb/download/v4.4/
In the kernel .config you should enable the following options:
CONFIG_KGDB=y
CONFIG_KGDB_SERIAL_CONSOLE=y
CONFIG_KGDB_LOW_LEVEL_TRAP=y
CONFIG_KGDB_KDB=y
CONFIG_KDB_KEYBOARD=y
To use kdb with a serial port you would use the kgdb/kgdboc way of
doing things. You would used a kernel command line with:
console=ttyS0,115200 kgdboc=ttyS0 kgdbwait
That will get you access to kdb just after the console has been
registered. If you want to use the keyboard, you could use the
following (NOTE it is kbd and not kdb, kbd is short for keyboard):
console=tty0 kgdboc=kbd kgdbwait
You can also use the keyboard and or serial console:
console=ttyS0,115200 console=tty0 kgdboc=kbd,ttyS0
In terms of breaking into the debugger after the system is up, you
must use the sysrq-g sequence. That means you could run:
echo g > /proc/sysrq-trigger
Or you can use the SysRq key on your key board. On a typical laptop
you might have to do the following:
press and hold ALT -- You will be holding this the whole time
press and hold FN
press and release the key with the SysRq label
release FN
press and release g
release ALT
Once you are in kdb you can run help to see a limited list of
commands.
You can also still connect gdb or re-enter kdb without leaving the
exception state, if you are using a serial port. To get out of kgdb
mode you can type "$3#33", or to get into kgdb mode from kdb, you can
type "kgdb".
>From gdb you can issue commands to the kdb front end, via gdb's
monitor command. For instance you could issue "monitor lsmod".
Allowing the gdb monitor extension was certainly another motivation
behind the prototype.
Included among the kdb patches are some kgdb specific fixes for the
next kernel merge window, and if kdb were to not make the cut, these
patches will be split out of the series. Anything too ugly for a
possible merge is also a candidate to get removed from the series.
Thanks,
Jason.
You can find the development branch for this here:
http://git.kernel.org/?p=linux/kernel/git/jwessel/linux-2.6-kgdb.git;a=shortlog;h=kdb_prototype11
or grab a static version of the patches here:
http://kernel.org/pub/linux/kernel/people/jwessel/branches/kdb_prototype11.tar.bz2
---
Jason Wessel (38):
softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume
x86,hw_breakpoint,kgdb: kgdb to use hw_breakpoint API
Move kernel/kgdb.c to kernel/debug/debug_core.c
Separate the gdbstub from the debug core
kgdb: eliminate kgdb_wait(), all cpus enter the same way
kgdb,sparc: Add in kgdb_arch_set_pc for sparc
kgdb,sh: update superh kgdb exception handling
kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin
kdb: core for kgdb back end (1 of 2)
kdb: core for kgdb back end (2 of 2)
kgdb: core changes to support kdb
kgdb,8250,pl011: Return immediately from console poll
sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code
sparc,sunzilog: Add console polling support for sunzilog serial driver
kgdb: gdb "monitor" -> kdb passthrough
kgdboc,keyboard: Keyboard driver for kdb with kgdb
kgdb,docs: Update the kgdb docs to include kdb
kgdb: remove post_primary_code references
x86,kgdb: Add low level debug hook
arm,kgdb: Add hook to catch an oops with debugger
powerpc,kgdb: Introduce low level trap catching
mips,kgdb: kdb low level trap catch and stack trace
kgdb: Add the ability to schedule a breakpoint via a tasklet
kgdboc,kdb: Allow kdb to work on a non open console port
printk,kdb: capture printk() when in kdb shell
keyboard, input: Add hook to input to allow low level event clear
debug_core,kdb: Allow the debug core to process a recursive debug entry
kdb,panic,debug_core: Allow the debug core to receive a panic before smp_send_stop()
MAINTAINERS: update kgdb, kdb, and debug_core info
kgdboc,debug_core: Add call backs to allow kernel mode switching
kms,kdb: Force unblank a console device
i915: when kgdb is active display compression should be off
drm_fb_helper: Preserve capability to use atomic kms
drm,i915 - atomic mutex hacks
kgdb,docs: Update the kgdb docs to include kms
kgdbts,sh: Add in breakpoint pc offset for superh
debug_core: Turn off tracing while in the debugger
ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
Jesse Barnes (2):
kgdb: add ops arg to kgdb console active & restore hooks
drm: add KGDB/KDB support Add support for KDB entry/exit.
Documentation/DocBook/kgdb.tmpl | 713 +++++++--
Documentation/kernel-parameters.txt | 18 +-
MAINTAINERS | 6 +-
arch/arm/include/asm/kgdb.h | 11 +
arch/arm/include/asm/kmap_types.h | 1 +
arch/arm/kernel/kgdb.c | 13 +
arch/arm/kernel/traps.c | 5 +
arch/blackfin/kernel/kgdb.c | 5 +
arch/mips/include/asm/kgdb.h | 2 +
arch/mips/kernel/kgdb.c | 27 +-
arch/mips/kernel/traps.c | 14 +
arch/powerpc/include/asm/kmap_types.h | 1 +
arch/powerpc/kernel/kgdb.c | 12 +-
arch/powerpc/kernel/traps.c | 7 +
arch/sh/kernel/kgdb.c | 14 +-
arch/sparc/kernel/kgdb_32.c | 6 +
arch/sparc/kernel/kgdb_64.c | 6 +
arch/x86/include/asm/kgdb.h | 3 +
arch/x86/kernel/hw_breakpoint.c | 5 +-
arch/x86/kernel/kgdb.c | 247 ++-
arch/x86/kernel/traps.c | 6 +
drivers/char/Makefile | 1 +
drivers/char/kdb_keyboard.c | 204 +++
drivers/char/kdb_keyboard.h | 143 ++
drivers/char/keyboard.c | 30 +-
drivers/gpu/drm/drm_fb_helper.c | 93 +-
drivers/gpu/drm/i915/intel_display.c | 114 ++-
drivers/input/input.c | 15 +
drivers/misc/kgdbts.c | 6 +
drivers/serial/8250.c | 4 +-
drivers/serial/amba-pl011.c | 6 +-
drivers/serial/kgdboc.c | 117 ++-
drivers/serial/sh-sci.c | 6 +-
drivers/serial/sunzilog.c | 50 +
drivers/video/console/fbcon.c | 7 +
fs/proc/internal.h | 4 +-
fs/proc/meminfo.c | 15 +-
fs/proc/mmu.c | 8 +-
include/asm-generic/kmap_types.h | 3 +-
include/drm/drm_crtc_helper.h | 2 +
include/drm/drm_fb_helper.h | 4 +
include/linux/input.h | 10 +
include/linux/kdb.h | 118 ++
include/linux/kgdb.h | 77 +-
include/linux/sched.h | 4 +
include/linux/serial_core.h | 1 +
include/linux/swap.h | 2 +
init/main.c | 6 +
kernel/Makefile | 2 +-
kernel/debug/Makefile | 8 +
kernel/debug/debug_core.c | 985 ++++++++++++
kernel/debug/debug_core.h | 82 +
kernel/debug/gdbstub.c | 1022 ++++++++++++
kernel/debug/kdb/.gitignore | 1 +
kernel/debug/kdb/Makefile | 24 +
kernel/debug/kdb/kdb_bp.c | 567 +++++++
kernel/debug/kdb/kdb_bt.c | 217 +++
kernel/debug/kdb/kdb_cmds | 32 +
kernel/debug/kdb/kdb_debugger.c | 167 ++
kernel/debug/kdb/kdb_io.c | 825 ++++++++++
kernel/debug/kdb/kdb_main.c | 2857 +++++++++++++++++++++++++++++++++
kernel/debug/kdb/kdb_private.h | 399 +++++
kernel/debug/kdb/kdb_support.c | 1007 ++++++++++++
kernel/debug/kms_hooks.c | 62 +
kernel/kallsyms.c | 21 +
kernel/kgdb.c | 1760 --------------------
kernel/module.c | 4 +
kernel/panic.c | 7 +-
kernel/printk.c | 25 +
kernel/sched.c | 7 +-
kernel/signal.c | 42 +
kernel/softlockup.c | 16 +
kernel/trace/Makefile | 3 +
kernel/trace/trace.c | 48 +-
kernel/trace/trace.h | 17 +
kernel/trace/trace_kdb.c | 116 ++
lib/Kconfig.kgdb | 24 +-
mm/swapfile.c | 10 +-
78 files changed, 10412 insertions(+), 2117 deletions(-)
create mode 100644 drivers/char/kdb_keyboard.c
create mode 100644 drivers/char/kdb_keyboard.h
create mode 100644 include/linux/kdb.h
create mode 100644 kernel/debug/Makefile
create mode 100644 kernel/debug/debug_core.c
create mode 100644 kernel/debug/debug_core.h
create mode 100644 kernel/debug/gdbstub.c
create mode 100644 kernel/debug/kdb/.gitignore
create mode 100644 kernel/debug/kdb/Makefile
create mode 100644 kernel/debug/kdb/kdb_bp.c
create mode 100644 kernel/debug/kdb/kdb_bt.c
create mode 100644 kernel/debug/kdb/kdb_cmds
create mode 100644 kernel/debug/kdb/kdb_debugger.c
create mode 100644 kernel/debug/kdb/kdb_io.c
create mode 100644 kernel/debug/kdb/kdb_main.c
create mode 100644 kernel/debug/kdb/kdb_private.h
create mode 100644 kernel/debug/kdb/kdb_support.c
create mode 100644 kernel/debug/kms_hooks.c
delete mode 100644 kernel/kgdb.c
create mode 100644 kernel/trace/trace_kdb.c
^ permalink raw reply [flat|nested] 56+ messages in thread
* [PATCH 01/40] softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
@ 2010-01-14 14:58 ` Jason Wessel
2010-01-14 14:58 ` [PATCH 02/40] x86,hw_breakpoint,kgdb: kgdb to use hw_breakpoint API Jason Wessel
` (39 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:58 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Dongdong Deng, peterz
When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is set sched_clock() gets the
time from hardware, such as from TSC. In this configuration kgdb will
report a softlock warning messages on resuming or detaching from a
debug session.
Sequence of events in the problem case:
1) "cpu sched clock" and "hardware time" are at 100 sec prior
to a call to kgdb_handle_exception()
2) Debugger waits in kgdb_handle_exception() for 80 sec and on exit
the following is called ... touch_softlockup_watchdog() -->
__raw_get_cpu_var(touch_timestamp) = 0;
3) "cpu sched clock" = 100s (it was not updated, because the interrupt
was disabled in kgdb) but the "hardware time" = 180 sec
4) The first timer interrupt after resuming from kgdb_handle_exception
updates the watchdog from the "cpu sched clock"
update_process_times() { ... run_local_timers() --> softlockup_tick()
--> check (touch_timestamp == 0) (it is "YES" here, we have set
"touch_timestamp = 0" at kgdb) --> __touch_softlockup_watchdog()
***(A)--> reset "touch_timestamp" to "get_timestamp()" (Here, the
"touch_timestamp" will still be set to 100s.) ...
scheduler_tick() ***(B)--> sched_clock_tick() (update "cpu sched
clock" to "hardware time" = 180s) ... }
5) The Second timer interrupt handler appears to have a large jump and
trips the softlockup warning.
update_process_times() { ... run_local_timers() --> softlockup_tick()
--> "cpu sched clock" - "touch_timestamp" = 180s-100s > 60s --> printk
"soft lockup error messages" ... }
note: ***(A) reset "touch_timestamp" to "get_timestamp(this_cpu)"
Why "touch_timestamp" is 100 sec, instead of 180 sec?
With the CONFIG_HAVE_UNSTABLE_SCHED_CLOCK" set the call trace of
get_timestamp() is:
get_timestamp(this_cpu) -->cpu_clock(this_cpu)
-->sched_clock_cpu(this_cpu) -->__update_sched_clock(sched_clock_data,
now)
The __update_sched_clock() function uses the GTOD tick value to create
a window to normalize the "now" values. So if "now" values is too big
for sched_clock_data, it will be ignored.
The fix is to invoke sched_clock_tick() to update "cpu sched clock" in
order to recover from this state. This is done by introducing the
function touch_softlockup_watchdog_sync(), which allows kgdb to
request that the sched clock is updated when the watchdog thread runs
the first time after a resume from kgdb.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Dongdong Deng <Dongdong.Deng@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: peterz@infradead.org
---
include/linux/sched.h | 4 ++++
kernel/kgdb.c | 6 +++---
kernel/softlockup.c | 16 ++++++++++++++++
3 files changed, 23 insertions(+), 3 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 8d4991b..112c621 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -310,6 +310,7 @@ extern void sched_show_task(struct task_struct *p);
#ifdef CONFIG_DETECT_SOFTLOCKUP
extern void softlockup_tick(void);
extern void touch_softlockup_watchdog(void);
+extern void touch_softlockup_watchdog_sync(void);
extern void touch_all_softlockup_watchdogs(void);
extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
void __user *buffer,
@@ -323,6 +324,9 @@ static inline void softlockup_tick(void)
static inline void touch_softlockup_watchdog(void)
{
}
+static inline void touch_softlockup_watchdog_sync(void)
+{
+}
static inline void touch_all_softlockup_watchdogs(void)
{
}
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
index 2eb517e..87f2cc5 100644
--- a/kernel/kgdb.c
+++ b/kernel/kgdb.c
@@ -596,7 +596,7 @@ static void kgdb_wait(struct pt_regs *regs)
/* Signal the primary CPU that we are done: */
atomic_set(&cpu_in_kgdb[cpu], 0);
- touch_softlockup_watchdog();
+ touch_softlockup_watchdog_sync();
clocksource_touch_watchdog();
local_irq_restore(flags);
}
@@ -1450,7 +1450,7 @@ acquirelock:
(kgdb_info[cpu].task &&
kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
atomic_set(&kgdb_active, -1);
- touch_softlockup_watchdog();
+ touch_softlockup_watchdog_sync();
clocksource_touch_watchdog();
local_irq_restore(flags);
@@ -1550,7 +1550,7 @@ kgdb_restore:
}
/* Free kgdb_active */
atomic_set(&kgdb_active, -1);
- touch_softlockup_watchdog();
+ touch_softlockup_watchdog_sync();
clocksource_touch_watchdog();
local_irq_restore(flags);
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index d225790..57f1295 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -79,6 +79,14 @@ void touch_softlockup_watchdog(void)
}
EXPORT_SYMBOL(touch_softlockup_watchdog);
+static int softlock_touch_sync[NR_CPUS];
+
+void touch_softlockup_watchdog_sync(void)
+{
+ softlock_touch_sync[raw_smp_processor_id()] = 1;
+ __raw_get_cpu_var(softlockup_touch_ts) = 0;
+}
+
void touch_all_softlockup_watchdogs(void)
{
int cpu;
@@ -118,6 +126,14 @@ void softlockup_tick(void)
}
if (touch_ts == 0) {
+ if (unlikely(softlock_touch_sync[this_cpu])) {
+ /*
+ * If the time stamp was touched atomically
+ * make sure the scheduler tick is up to date.
+ */
+ softlock_touch_sync[this_cpu] = 0;
+ sched_clock_tick();
+ }
__touch_softlockup_watchdog();
return;
}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 02/40] x86,hw_breakpoint,kgdb: kgdb to use hw_breakpoint API
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
2010-01-14 14:58 ` [PATCH 01/40] softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume Jason Wessel
@ 2010-01-14 14:58 ` Jason Wessel
2010-01-14 14:58 ` [PATCH 03/40] Move kernel/kgdb.c to kernel/debug/debug_core.c Jason Wessel
` (38 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:58 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
In the 2.6.33 kernel, the hw_breakpoint API is now used for the
performance event counters. The hw_breakpoint_handler() now consumes
the hw breakpoints that were previously set by kgdb arch specific
code. In order for kgdb to work in conjunction with this core API
change, kgdb must use some of the low level functions of the
hw_breakpoint API to install, uninstall, and receive call backs for hw
breakpoints.
The kgdb core needs to call kgdb_disable_hw_debug anytime a slave cpu
enters kgdb_wait() in order to keep all the hw breakpoints in sync as
well as to prevent hitting a hw breakpoint while kgdb is active.
During the architecture specific initialization of kgdb, it will
pre-allocate 4 disabled (struct perf event **) structures. Kgdb will
use these to manage the capabilities for the 4 hw breakpoint
registers. Right now the hw_breakpoint API does not have a way to ask
how many breakpoints are available, on each CPU so it is possible that
the install of a breakpoint might fail when kgdb restores the system
to the run state. The intent of this patch is to first get the basic
functionality of hw breakpoints working and leave it to the person
debugging the kernel to understand what hw breakpoints are in use and
what restrictions have been imposed as a result.
While atomic, the x86 specific kgdb code will call
arch_uninstall_hw_breakpoint() and arch_install_hw_breakpoint() to
manage the cpu specific hw breakpoints.
The arch specific hw_breakpoint_handler() was changed to restore the
cpu specific dr7 instead of the dr7 that was locally saved, because
the dr7 can be modified while in a call back to kgdb.
The net result of these changes allow kgdb to use the same pool of
hw_breakpoints that are used by the perf event API, but neither knows
about future reservations for the available hw breakpoint slots.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/x86/kernel/hw_breakpoint.c | 5 +-
arch/x86/kernel/kgdb.c | 191 +++++++++++++++++++++++++++------------
kernel/kgdb.c | 3 +
3 files changed, 139 insertions(+), 60 deletions(-)
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index 05d5fec..cbf19e0 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -466,7 +466,7 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
{
int i, cpu, rc = NOTIFY_STOP;
struct perf_event *bp;
- unsigned long dr7, dr6;
+ unsigned long dr6;
unsigned long *dr6_p;
/* The DR6 value is pointed by args->err */
@@ -477,7 +477,6 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
if ((dr6 & DR_TRAP_BITS) == 0)
return NOTIFY_DONE;
- get_debugreg(dr7, 7);
/* Disable breakpoints during exception handling */
set_debugreg(0UL, 7);
/*
@@ -525,7 +524,7 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
if (dr6 & (~DR_TRAP_BITS))
rc = NOTIFY_DONE;
- set_debugreg(dr7, 7);
+ set_debugreg(__get_cpu_var(cpu_dr7), 7);
put_cpu();
return rc;
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index dd74fe7..48384fa 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -42,6 +42,7 @@
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/nmi.h>
+#include <linux/hw_breakpoint.h>
#include <asm/debugreg.h>
#include <asm/apicdef.h>
@@ -204,40 +205,27 @@ void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
static struct hw_breakpoint {
unsigned enabled;
- unsigned type;
- unsigned len;
unsigned long addr;
+ struct perf_event **pev;
} breakinfo[4];
static void kgdb_correct_hw_break(void)
{
- unsigned long dr7;
- int correctit = 0;
- int breakbit;
int breakno;
- get_debugreg(dr7, 7);
for (breakno = 0; breakno < 4; breakno++) {
- breakbit = 2 << (breakno << 1);
- if (!(dr7 & breakbit) && breakinfo[breakno].enabled) {
- correctit = 1;
- dr7 |= breakbit;
- dr7 &= ~(0xf0000 << (breakno << 2));
- dr7 |= ((breakinfo[breakno].len << 2) |
- breakinfo[breakno].type) <<
- ((breakno << 2) + 16);
- set_debugreg(breakinfo[breakno].addr, breakno);
-
- } else {
- if ((dr7 & breakbit) && !breakinfo[breakno].enabled) {
- correctit = 1;
- dr7 &= ~breakbit;
- dr7 &= ~(0xf0000 << (breakno << 2));
- }
- }
+ struct perf_event *bp;
+ int val;
+ int cpu = raw_smp_processor_id();
+ if (!breakinfo[breakno].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[breakno].pev, cpu);
+ if (bp->attr.disabled != 1)
+ continue;
+ val = arch_install_hw_breakpoint(bp);
+ if (!val)
+ bp->attr.disabled = 0;
}
- if (correctit)
- set_debugreg(dr7, 7);
}
static int
@@ -259,46 +247,74 @@ kgdb_remove_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
static void kgdb_remove_all_hw_break(void)
{
int i;
+ int cpu = raw_smp_processor_id();
+ struct perf_event *bp;
- for (i = 0; i < 4; i++)
- memset(&breakinfo[i], 0, sizeof(struct hw_breakpoint));
+ for (i = 0; i < 4; i++) {
+ if (!breakinfo[i].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
+ if (bp->attr.disabled == 1)
+ continue;
+ arch_uninstall_hw_breakpoint(bp);
+ bp->attr.disabled = 1;
+ }
}
static int
kgdb_set_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
{
- unsigned type;
int i;
+ struct perf_event *bp;
+ struct arch_hw_breakpoint *info;
for (i = 0; i < 4; i++)
if (!breakinfo[i].enabled)
break;
if (i == 4)
return -1;
-
+ bp = *per_cpu_ptr(breakinfo[i].pev, raw_smp_processor_id());
+ info = counter_arch_bp(bp);
switch (bptype) {
case BP_HARDWARE_BREAKPOINT:
- type = 0;
- len = 1;
+ len = 1;
+ info->type = X86_BREAKPOINT_EXECUTE;
break;
case BP_WRITE_WATCHPOINT:
- type = 1;
+ info->type = X86_BREAKPOINT_WRITE;
break;
case BP_ACCESS_WATCHPOINT:
- type = 3;
+ info->type = X86_BREAKPOINT_RW;
break;
default:
return -1;
}
- if (len == 1 || len == 2 || len == 4)
- breakinfo[i].len = len - 1;
- else
+ switch (len) {
+ case 1:
+ info->len = X86_BREAKPOINT_LEN_1;
+ break;
+ case 2:
+ info->len = X86_BREAKPOINT_LEN_2;
+ break;
+ case 4:
+ info->len = X86_BREAKPOINT_LEN_4;
+ break;
+#ifdef CONFIG_X86_64
+ case 8:
+ info->len = X86_BREAKPOINT_LEN_8;
+ break;
+#endif
+ default:
return -1;
+ }
- breakinfo[i].enabled = 1;
breakinfo[i].addr = addr;
- breakinfo[i].type = type;
+ info->address = addr;
+ bp->attr.bp_addr = info->address;
+ bp->attr.bp_len = info->len;
+ bp->attr.bp_type = info->type;
+ breakinfo[i].enabled = 1;
return 0;
}
@@ -313,8 +329,21 @@ kgdb_set_hw_break(unsigned long addr, int len, enum kgdb_bptype bptype)
*/
void kgdb_disable_hw_debug(struct pt_regs *regs)
{
+ int i;
+ int cpu = raw_smp_processor_id();
+ struct perf_event *bp;
+
/* Disable hardware debugging while we are in kgdb: */
set_debugreg(0UL, 7);
+ for (i = 0; i < 4; i++) {
+ if (!breakinfo[i].enabled)
+ continue;
+ bp = *per_cpu_ptr(breakinfo[i].pev, cpu);
+ if (bp->attr.disabled == 1)
+ continue;
+ arch_uninstall_hw_breakpoint(bp);
+ bp->attr.disabled = 1;
+ }
}
/**
@@ -378,7 +407,6 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
struct pt_regs *linux_regs)
{
unsigned long addr;
- unsigned long dr6;
char *ptr;
int newPC;
@@ -404,20 +432,6 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
raw_smp_processor_id());
}
- get_debugreg(dr6, 6);
- if (!(dr6 & 0x4000)) {
- int breakno;
-
- for (breakno = 0; breakno < 4; breakno++) {
- if (dr6 & (1 << breakno) &&
- breakinfo[breakno].type == 0) {
- /* Set restore flag: */
- linux_regs->flags |= X86_EFLAGS_RF;
- break;
- }
- }
- }
- set_debugreg(0UL, 6);
kgdb_correct_hw_break();
return 0;
@@ -448,6 +462,7 @@ single_step_cont(struct pt_regs *regs, struct die_args *args)
}
static int was_in_debug_nmi[NR_CPUS];
+static int recieved_hw_brk[NR_CPUS];
static int __kgdb_notify(struct die_args *args, unsigned long cmd)
{
@@ -485,16 +500,19 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
break;
case DIE_DEBUG:
- if (atomic_read(&kgdb_cpu_doing_single_step) ==
- raw_smp_processor_id()) {
+ if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
if (user_mode(regs))
return single_step_cont(regs, args);
break;
- } else if (test_thread_flag(TIF_SINGLESTEP))
+ } else if (test_thread_flag(TIF_SINGLESTEP)) {
/* This means a user thread is single stepping
* a system call which should be ignored
*/
return NOTIFY_DONE;
+ } else if (recieved_hw_brk[raw_smp_processor_id()] == 1) {
+ recieved_hw_brk[raw_smp_processor_id()] = 0;
+ return NOTIFY_STOP;
+ }
/* fall through */
default:
if (user_mode(regs))
@@ -531,6 +549,23 @@ static struct notifier_block kgdb_notifier = {
.priority = -INT_MAX,
};
+static void kgdb_hw_bp(struct perf_event *bp, int nmi,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ struct die_args args;
+
+ args.trapnr = 0;
+ args.signr = 5;
+ args.err = 0;
+ args.regs = regs;
+ args.str = "debug";
+ if (__kgdb_notify(&args, DIE_DEBUG) == NOTIFY_STOP)
+ recieved_hw_brk[raw_smp_processor_id()] = 1;
+ else
+ recieved_hw_brk[raw_smp_processor_id()] = 0;
+}
+
/**
* kgdb_arch_init - Perform any architecture specific initalization.
*
@@ -539,7 +574,42 @@ static struct notifier_block kgdb_notifier = {
*/
int kgdb_arch_init(void)
{
- return register_die_notifier(&kgdb_notifier);
+ int i, cpu;
+ int ret;
+ struct perf_event_attr attr;
+ struct perf_event **pevent;
+
+ ret = register_die_notifier(&kgdb_notifier);
+ if (ret != 0)
+ return ret;
+ /*
+ * Pre-allocate the hw breakpoint structions in the non-atomic
+ * portion of kgdb because this operation requires mutexs to
+ * complete.
+ */
+ attr.bp_addr = (unsigned long)kgdb_arch_init;
+ attr.type = PERF_TYPE_BREAKPOINT;
+ attr.bp_len = HW_BREAKPOINT_LEN_1;
+ attr.bp_type = HW_BREAKPOINT_X;
+ attr.disabled = 1;
+ for (i = 0; i < 4; i++) {
+ breakinfo[i].pev = register_wide_hw_breakpoint(&attr,
+ kgdb_hw_bp);
+ if (IS_ERR(breakinfo[i].pev)) {
+ printk(KERN_ERR "kgdb: Could not allocate hw breakpoints\n");
+ breakinfo[i].pev = NULL;
+ kgdb_arch_exit();
+ return -1;
+ }
+ for_each_online_cpu(cpu) {
+ pevent = per_cpu_ptr(breakinfo[i].pev, cpu);
+ if (pevent[0]->destroy != NULL) {
+ pevent[0]->destroy = NULL;
+ release_bp_slot(*pevent);
+ }
+ }
+ }
+ return ret;
}
/**
@@ -550,6 +620,13 @@ int kgdb_arch_init(void)
*/
void kgdb_arch_exit(void)
{
+ int i;
+ for (i = 0; i < 4; i++) {
+ if (breakinfo[i].pev) {
+ unregister_wide_hw_breakpoint(breakinfo[i].pev);
+ breakinfo[i].pev = NULL;
+ }
+ }
unregister_die_notifier(&kgdb_notifier);
}
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
index 87f2cc5..761fdd2 100644
--- a/kernel/kgdb.c
+++ b/kernel/kgdb.c
@@ -583,6 +583,9 @@ static void kgdb_wait(struct pt_regs *regs)
smp_wmb();
atomic_set(&cpu_in_kgdb[cpu], 1);
+ /* Disable any cpu specific hw breakpoints */
+ kgdb_disable_hw_debug(regs);
+
/* Wait till primary CPU is done with debugging */
while (atomic_read(&passive_cpu_wait[cpu]))
cpu_relax();
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 03/40] Move kernel/kgdb.c to kernel/debug/debug_core.c
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
2010-01-14 14:58 ` [PATCH 01/40] softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume Jason Wessel
2010-01-14 14:58 ` [PATCH 02/40] x86,hw_breakpoint,kgdb: kgdb to use hw_breakpoint API Jason Wessel
@ 2010-01-14 14:58 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 04/40] Separate the gdbstub from the debug core Jason Wessel
` (37 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:58 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Move kgdb.c in preparation for to separate the gdbstub from the debug
core and exception handling.n
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/Makefile | 2 +-
kernel/debug/Makefile | 5 +
kernel/debug/debug_core.c | 1763 +++++++++++++++++++++++++++++++++++++++++++++
kernel/kgdb.c | 1763 ---------------------------------------------
4 files changed, 1769 insertions(+), 1764 deletions(-)
create mode 100644 kernel/debug/Makefile
create mode 100644 kernel/debug/debug_core.c
delete mode 100644 kernel/kgdb.c
diff --git a/kernel/Makefile b/kernel/Makefile
index 864ff75..a18b039 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -74,7 +74,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
obj-$(CONFIG_GCOV_KERNEL) += gcov/
obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
obj-$(CONFIG_KPROBES) += kprobes.o
-obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_KGDB) += debug/
obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile
new file mode 100644
index 0000000..5287fc8
--- /dev/null
+++ b/kernel/debug/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for the linux kernel debugger
+#
+
+obj-$(CONFIG_KGDB) += debug_core.o
\ No newline at end of file
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
new file mode 100644
index 0000000..761fdd2
--- /dev/null
+++ b/kernel/debug/debug_core.c
@@ -0,0 +1,1763 @@
+/*
+ * KGDB stub.
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002-2004 Timesys Corporation
+ * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
+ * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2005-2008 Wind River Systems, Inc.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ * Contributors at various stages not listed above:
+ * Jason Wessel ( jason.wessel@windriver.com )
+ * George Anzinger <george@mvista.com>
+ * Anurekh Saxena (anurekh.saxena@timesys.com)
+ * Lake Stevens Instrument Division (Glenn Engel)
+ * Jim Kingdon, Cygnus Support.
+ *
+ * Original KGDB stub: David Grothe <dave@gcom.com>,
+ * Tigran Aivazian <tigran@sco.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+#include <linux/pid_namespace.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/console.h>
+#include <linux/threads.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/ptrace.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/sysrq.h>
+#include <linux/init.h>
+#include <linux/kgdb.h>
+#include <linux/pid.h>
+#include <linux/smp.h>
+#include <linux/mm.h>
+
+#include <asm/cacheflush.h>
+#include <asm/byteorder.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/unaligned.h>
+
+static int kgdb_break_asap;
+
+#define KGDB_MAX_THREAD_QUERY 17
+struct kgdb_state {
+ int ex_vector;
+ int signo;
+ int err_code;
+ int cpu;
+ int pass_exception;
+ unsigned long thr_query;
+ unsigned long threadid;
+ long kgdb_usethreadid;
+ struct pt_regs *linux_regs;
+};
+
+static struct debuggerinfo_struct {
+ void *debuggerinfo;
+ struct task_struct *task;
+} kgdb_info[NR_CPUS];
+
+/**
+ * kgdb_connected - Is a host GDB connected to us?
+ */
+int kgdb_connected;
+EXPORT_SYMBOL_GPL(kgdb_connected);
+
+/* All the KGDB handlers are installed */
+static int kgdb_io_module_registered;
+
+/* Guard for recursive entry */
+static int exception_level;
+
+static struct kgdb_io *kgdb_io_ops;
+static DEFINE_SPINLOCK(kgdb_registration_lock);
+
+/* kgdb console driver is loaded */
+static int kgdb_con_registered;
+/* determine if kgdb console output should be used */
+static int kgdb_use_con;
+
+static int __init opt_kgdb_con(char *str)
+{
+ kgdb_use_con = 1;
+ return 0;
+}
+
+early_param("kgdbcon", opt_kgdb_con);
+
+module_param(kgdb_use_con, int, 0644);
+
+/*
+ * Holds information about breakpoints in a kernel. These breakpoints are
+ * added and removed by gdb.
+ */
+static struct kgdb_bkpt kgdb_break[KGDB_MAX_BREAKPOINTS] = {
+ [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED }
+};
+
+/*
+ * The CPU# of the active CPU, or -1 if none:
+ */
+atomic_t kgdb_active = ATOMIC_INIT(-1);
+
+/*
+ * We use NR_CPUs not PERCPU, in case kgdb is used to debug early
+ * bootup code (which might not have percpu set up yet):
+ */
+static atomic_t passive_cpu_wait[NR_CPUS];
+static atomic_t cpu_in_kgdb[NR_CPUS];
+atomic_t kgdb_setting_breakpoint;
+
+struct task_struct *kgdb_usethread;
+struct task_struct *kgdb_contthread;
+
+int kgdb_single_step;
+pid_t kgdb_sstep_pid;
+
+/* Our I/O buffers. */
+static char remcom_in_buffer[BUFMAX];
+static char remcom_out_buffer[BUFMAX];
+
+/* Storage for the registers, in GDB format. */
+static unsigned long gdb_regs[(NUMREGBYTES +
+ sizeof(unsigned long) - 1) /
+ sizeof(unsigned long)];
+
+/* to keep track of the CPU which is doing the single stepping*/
+atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
+
+/*
+ * If you are debugging a problem where roundup (the collection of
+ * all other CPUs) is a problem [this should be extremely rare],
+ * then use the nokgdbroundup option to avoid roundup. In that case
+ * the other CPUs might interfere with your debugging context, so
+ * use this with care:
+ */
+static int kgdb_do_roundup = 1;
+
+static int __init opt_nokgdbroundup(char *str)
+{
+ kgdb_do_roundup = 0;
+
+ return 0;
+}
+
+early_param("nokgdbroundup", opt_nokgdbroundup);
+
+/*
+ * Finally, some KGDB code :-)
+ */
+
+/*
+ * Weak aliases for breakpoint management,
+ * can be overriden by architectures when needed:
+ */
+int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
+{
+ int err;
+
+ err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
+ if (err)
+ return err;
+
+ return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
+ BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
+{
+ return probe_kernel_write((char *)addr,
+ (char *)bundle, BREAK_INSTR_SIZE);
+}
+
+int __weak kgdb_validate_break_address(unsigned long addr)
+{
+ char tmp_variable[BREAK_INSTR_SIZE];
+ int err;
+ /* Validate setting the breakpoint and then removing it. In the
+ * remove fails, the kernel needs to emit a bad message because we
+ * are deep trouble not being able to put things back the way we
+ * found them.
+ */
+ err = kgdb_arch_set_breakpoint(addr, tmp_variable);
+ if (err)
+ return err;
+ err = kgdb_arch_remove_breakpoint(addr, tmp_variable);
+ if (err)
+ printk(KERN_ERR "KGDB: Critical breakpoint error, kernel "
+ "memory destroyed at: %lx", addr);
+ return err;
+}
+
+unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs)
+{
+ return instruction_pointer(regs);
+}
+
+int __weak kgdb_arch_init(void)
+{
+ return 0;
+}
+
+int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
+{
+ return 0;
+}
+
+void __weak
+kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
+{
+ return;
+}
+
+/**
+ * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
+ * @regs: Current &struct pt_regs.
+ *
+ * This function will be called if the particular architecture must
+ * disable hardware debugging while it is processing gdb packets or
+ * handling exception.
+ */
+void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
+{
+}
+
+/*
+ * GDB remote protocol parser:
+ */
+
+static int hex(char ch)
+{
+ if ((ch >= 'a') && (ch <= 'f'))
+ return ch - 'a' + 10;
+ if ((ch >= '0') && (ch <= '9'))
+ return ch - '0';
+ if ((ch >= 'A') && (ch <= 'F'))
+ return ch - 'A' + 10;
+ return -1;
+}
+
+/* scan for the sequence $<data>#<checksum> */
+static void get_packet(char *buffer)
+{
+ unsigned char checksum;
+ unsigned char xmitcsum;
+ int count;
+ char ch;
+
+ do {
+ /*
+ * Spin and wait around for the start character, ignore all
+ * other characters:
+ */
+ while ((ch = (kgdb_io_ops->read_char())) != '$')
+ /* nothing */;
+
+ kgdb_connected = 1;
+ checksum = 0;
+ xmitcsum = -1;
+
+ count = 0;
+
+ /*
+ * now, read until a # or end of buffer is found:
+ */
+ while (count < (BUFMAX - 1)) {
+ ch = kgdb_io_ops->read_char();
+ if (ch == '#')
+ break;
+ checksum = checksum + ch;
+ buffer[count] = ch;
+ count = count + 1;
+ }
+ buffer[count] = 0;
+
+ if (ch == '#') {
+ xmitcsum = hex(kgdb_io_ops->read_char()) << 4;
+ xmitcsum += hex(kgdb_io_ops->read_char());
+
+ if (checksum != xmitcsum)
+ /* failed checksum */
+ kgdb_io_ops->write_char('-');
+ else
+ /* successful transfer */
+ kgdb_io_ops->write_char('+');
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+ }
+ } while (checksum != xmitcsum);
+}
+
+/*
+ * Send the packet in buffer.
+ * Check for gdb connection if asked for.
+ */
+static void put_packet(char *buffer)
+{
+ unsigned char checksum;
+ int count;
+ char ch;
+
+ /*
+ * $<packet info>#<checksum>.
+ */
+ while (1) {
+ kgdb_io_ops->write_char('$');
+ checksum = 0;
+ count = 0;
+
+ while ((ch = buffer[count])) {
+ kgdb_io_ops->write_char(ch);
+ checksum += ch;
+ count++;
+ }
+
+ kgdb_io_ops->write_char('#');
+ kgdb_io_ops->write_char(hex_asc_hi(checksum));
+ kgdb_io_ops->write_char(hex_asc_lo(checksum));
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+
+ /* Now see what we get in reply. */
+ ch = kgdb_io_ops->read_char();
+
+ if (ch == 3)
+ ch = kgdb_io_ops->read_char();
+
+ /* If we get an ACK, we are done. */
+ if (ch == '+')
+ return;
+
+ /*
+ * If we get the start of another packet, this means
+ * that GDB is attempting to reconnect. We will NAK
+ * the packet being sent, and stop trying to send this
+ * packet.
+ */
+ if (ch == '$') {
+ kgdb_io_ops->write_char('-');
+ if (kgdb_io_ops->flush)
+ kgdb_io_ops->flush();
+ return;
+ }
+ }
+}
+
+/*
+ * Convert the memory pointed to by mem into hex, placing result in buf.
+ * Return a pointer to the last char put in buf (null). May return an error.
+ */
+int kgdb_mem2hex(char *mem, char *buf, int count)
+{
+ char *tmp;
+ int err;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory copy. Hex conversion will work against this one.
+ */
+ tmp = buf + count;
+
+ err = probe_kernel_read(tmp, mem, count);
+ if (!err) {
+ while (count > 0) {
+ buf = pack_hex_byte(buf, *tmp);
+ tmp++;
+ count--;
+ }
+
+ *buf = 0;
+ }
+
+ return err;
+}
+
+/*
+ * Copy the binary array pointed to by buf into mem. Fix $, #, and
+ * 0x7d escaped with 0x7d. Return a pointer to the character after
+ * the last byte written.
+ */
+static int kgdb_ebin2mem(char *buf, char *mem, int count)
+{
+ int err = 0;
+ char c;
+
+ while (count-- > 0) {
+ c = *buf++;
+ if (c == 0x7d)
+ c = *buf++ ^ 0x20;
+
+ err = probe_kernel_write(mem, &c, 1);
+ if (err)
+ break;
+
+ mem++;
+ }
+
+ return err;
+}
+
+/*
+ * Convert the hex array pointed to by buf into binary to be placed in mem.
+ * Return a pointer to the character AFTER the last byte written.
+ * May return an error.
+ */
+int kgdb_hex2mem(char *buf, char *mem, int count)
+{
+ char *tmp_raw;
+ char *tmp_hex;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory that is converted from hex.
+ */
+ tmp_raw = buf + count * 2;
+
+ tmp_hex = tmp_raw - 1;
+ while (tmp_hex >= buf) {
+ tmp_raw--;
+ *tmp_raw = hex(*tmp_hex--);
+ *tmp_raw |= hex(*tmp_hex--) << 4;
+ }
+
+ return probe_kernel_write(mem, tmp_raw, count);
+}
+
+/*
+ * While we find nice hex chars, build a long_val.
+ * Return number of chars processed.
+ */
+int kgdb_hex2long(char **ptr, unsigned long *long_val)
+{
+ int hex_val;
+ int num = 0;
+ int negate = 0;
+
+ *long_val = 0;
+
+ if (**ptr == '-') {
+ negate = 1;
+ (*ptr)++;
+ }
+ while (**ptr) {
+ hex_val = hex(**ptr);
+ if (hex_val < 0)
+ break;
+
+ *long_val = (*long_val << 4) | hex_val;
+ num++;
+ (*ptr)++;
+ }
+
+ if (negate)
+ *long_val = -*long_val;
+
+ return num;
+}
+
+/* Write memory due to an 'M' or 'X' packet. */
+static int write_mem_msg(int binary)
+{
+ char *ptr = &remcom_in_buffer[1];
+ unsigned long addr;
+ unsigned long length;
+ int err;
+
+ if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
+ kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
+ if (binary)
+ err = kgdb_ebin2mem(ptr, (char *)addr, length);
+ else
+ err = kgdb_hex2mem(ptr, (char *)addr, length);
+ if (err)
+ return err;
+ if (CACHE_FLUSH_IS_SAFE)
+ flush_icache_range(addr, addr + length);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static void error_packet(char *pkt, int error)
+{
+ error = -error;
+ pkt[0] = 'E';
+ pkt[1] = hex_asc[(error / 10)];
+ pkt[2] = hex_asc[(error % 10)];
+ pkt[3] = '\0';
+}
+
+/*
+ * Thread ID accessors. We represent a flat TID space to GDB, where
+ * the per CPU idle threads (which under Linux all have PID 0) are
+ * remapped to negative TIDs.
+ */
+
+#define BUF_THREAD_ID_SIZE 16
+
+static char *pack_threadid(char *pkt, unsigned char *id)
+{
+ char *limit;
+
+ limit = pkt + BUF_THREAD_ID_SIZE;
+ while (pkt < limit)
+ pkt = pack_hex_byte(pkt, *id++);
+
+ return pkt;
+}
+
+static void int_to_threadref(unsigned char *id, int value)
+{
+ unsigned char *scan;
+ int i = 4;
+
+ scan = (unsigned char *)id;
+ while (i--)
+ *scan++ = 0;
+ put_unaligned_be32(value, scan);
+}
+
+static struct task_struct *getthread(struct pt_regs *regs, int tid)
+{
+ /*
+ * Non-positive TIDs are remapped to the cpu shadow information
+ */
+ if (tid == 0 || tid == -1)
+ tid = -atomic_read(&kgdb_active) - 2;
+ if (tid < -1 && tid > -NR_CPUS - 2) {
+ if (kgdb_info[-tid - 2].task)
+ return kgdb_info[-tid - 2].task;
+ else
+ return idle_task(-tid - 2);
+ }
+ if (tid <= 0) {
+ printk(KERN_ERR "KGDB: Internal thread select error\n");
+ dump_stack();
+ return NULL;
+ }
+
+ /*
+ * find_task_by_pid_ns() does not take the tasklist lock anymore
+ * but is nicely RCU locked - hence is a pretty resilient
+ * thing to use:
+ */
+ return find_task_by_pid_ns(tid, &init_pid_ns);
+}
+
+/*
+ * CPU debug state control:
+ */
+
+#ifdef CONFIG_SMP
+static void kgdb_wait(struct pt_regs *regs)
+{
+ unsigned long flags;
+ int cpu;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ kgdb_info[cpu].debuggerinfo = regs;
+ kgdb_info[cpu].task = current;
+ /*
+ * Make sure the above info reaches the primary CPU before
+ * our cpu_in_kgdb[] flag setting does:
+ */
+ smp_wmb();
+ atomic_set(&cpu_in_kgdb[cpu], 1);
+
+ /* Disable any cpu specific hw breakpoints */
+ kgdb_disable_hw_debug(regs);
+
+ /* Wait till primary CPU is done with debugging */
+ while (atomic_read(&passive_cpu_wait[cpu]))
+ cpu_relax();
+
+ kgdb_info[cpu].debuggerinfo = NULL;
+ kgdb_info[cpu].task = NULL;
+
+ /* fix up hardware debug registers on local cpu */
+ if (arch_kgdb_ops.correct_hw_break)
+ arch_kgdb_ops.correct_hw_break();
+
+ /* Signal the primary CPU that we are done: */
+ atomic_set(&cpu_in_kgdb[cpu], 0);
+ touch_softlockup_watchdog_sync();
+ clocksource_touch_watchdog();
+ local_irq_restore(flags);
+}
+#endif
+
+/*
+ * Some architectures need cache flushes when we set/clear a
+ * breakpoint:
+ */
+static void kgdb_flush_swbreak_addr(unsigned long addr)
+{
+ if (!CACHE_FLUSH_IS_SAFE)
+ return;
+
+ if (current->mm && current->mm->mmap_cache) {
+ flush_cache_range(current->mm->mmap_cache,
+ addr, addr + BREAK_INSTR_SIZE);
+ }
+ /* Force flush instruction cache if it was outside the mm */
+ flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
+}
+
+/*
+ * SW breakpoint management:
+ */
+static int kgdb_activate_sw_breakpoints(void)
+{
+ unsigned long addr;
+ int error;
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_SET)
+ continue;
+
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_set_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if (error) {
+ ret = error;
+ printk(KERN_INFO "KGDB: BP install failed: %lx", addr);
+ continue;
+ }
+
+ kgdb_flush_swbreak_addr(addr);
+ kgdb_break[i].state = BP_ACTIVE;
+ }
+ return ret;
+}
+
+static int kgdb_set_sw_break(unsigned long addr)
+{
+ int err = kgdb_validate_break_address(addr);
+ int breakno = -1;
+ int i;
+
+ if (err)
+ return err;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_SET) &&
+ (kgdb_break[i].bpt_addr == addr))
+ return -EEXIST;
+ }
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state == BP_REMOVED &&
+ kgdb_break[i].bpt_addr == addr) {
+ breakno = i;
+ break;
+ }
+ }
+
+ if (breakno == -1) {
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state == BP_UNDEFINED) {
+ breakno = i;
+ break;
+ }
+ }
+ }
+
+ if (breakno == -1)
+ return -E2BIG;
+
+ kgdb_break[breakno].state = BP_SET;
+ kgdb_break[breakno].type = BP_BREAKPOINT;
+ kgdb_break[breakno].bpt_addr = addr;
+
+ return 0;
+}
+
+static int kgdb_deactivate_sw_breakpoints(void)
+{
+ unsigned long addr;
+ int error;
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_ACTIVE)
+ continue;
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_remove_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if (error) {
+ printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);
+ ret = error;
+ }
+
+ kgdb_flush_swbreak_addr(addr);
+ kgdb_break[i].state = BP_SET;
+ }
+ return ret;
+}
+
+static int kgdb_remove_sw_break(unsigned long addr)
+{
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_SET) &&
+ (kgdb_break[i].bpt_addr == addr)) {
+ kgdb_break[i].state = BP_REMOVED;
+ return 0;
+ }
+ }
+ return -ENOENT;
+}
+
+int kgdb_isremovedbreak(unsigned long addr)
+{
+ int i;
+
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if ((kgdb_break[i].state == BP_REMOVED) &&
+ (kgdb_break[i].bpt_addr == addr))
+ return 1;
+ }
+ return 0;
+}
+
+static int remove_all_break(void)
+{
+ unsigned long addr;
+ int error;
+ int i;
+
+ /* Clear memory breakpoints. */
+ for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
+ if (kgdb_break[i].state != BP_ACTIVE)
+ goto setundefined;
+ addr = kgdb_break[i].bpt_addr;
+ error = kgdb_arch_remove_breakpoint(addr,
+ kgdb_break[i].saved_instr);
+ if (error)
+ printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n",
+ addr);
+setundefined:
+ kgdb_break[i].state = BP_UNDEFINED;
+ }
+
+ /* Clear hardware breakpoints. */
+ if (arch_kgdb_ops.remove_all_hw_break)
+ arch_kgdb_ops.remove_all_hw_break();
+
+ return 0;
+}
+
+/*
+ * Remap normal tasks to their real PID,
+ * CPU shadow threads are mapped to -CPU - 2
+ */
+static inline int shadow_pid(int realpid)
+{
+ if (realpid)
+ return realpid;
+
+ return -raw_smp_processor_id() - 2;
+}
+
+static char gdbmsgbuf[BUFMAX + 1];
+
+static void kgdb_msg_write(const char *s, int len)
+{
+ char *bufptr;
+ int wcount;
+ int i;
+
+ /* 'O'utput */
+ gdbmsgbuf[0] = 'O';
+
+ /* Fill and send buffers... */
+ while (len > 0) {
+ bufptr = gdbmsgbuf + 1;
+
+ /* Calculate how many this time */
+ if ((len << 1) > (BUFMAX - 2))
+ wcount = (BUFMAX - 2) >> 1;
+ else
+ wcount = len;
+
+ /* Pack in hex chars */
+ for (i = 0; i < wcount; i++)
+ bufptr = pack_hex_byte(bufptr, s[i]);
+ *bufptr = '\0';
+
+ /* Move up */
+ s += wcount;
+ len -= wcount;
+
+ /* Write packet */
+ put_packet(gdbmsgbuf);
+ }
+}
+
+/*
+ * Return true if there is a valid kgdb I/O module. Also if no
+ * debugger is attached a message can be printed to the console about
+ * waiting for the debugger to attach.
+ *
+ * The print_wait argument is only to be true when called from inside
+ * the core kgdb_handle_exception, because it will wait for the
+ * debugger to attach.
+ */
+static int kgdb_io_ready(int print_wait)
+{
+ if (!kgdb_io_ops)
+ return 0;
+ if (kgdb_connected)
+ return 1;
+ if (atomic_read(&kgdb_setting_breakpoint))
+ return 1;
+ if (print_wait)
+ printk(KERN_CRIT "KGDB: Waiting for remote debugger\n");
+ return 1;
+}
+
+/*
+ * All the functions that start with gdb_cmd are the various
+ * operations to implement the handlers for the gdbserial protocol
+ * where KGDB is communicating with an external debugger
+ */
+
+/* Handle the '?' status packets */
+static void gdb_cmd_status(struct kgdb_state *ks)
+{
+ /*
+ * We know that this packet is only sent
+ * during initial connect. So to be safe,
+ * we clear out our breakpoints now in case
+ * GDB is reconnecting.
+ */
+ remove_all_break();
+
+ remcom_out_buffer[0] = 'S';
+ pack_hex_byte(&remcom_out_buffer[1], ks->signo);
+}
+
+/* Handle the 'g' get registers request */
+static void gdb_cmd_getregs(struct kgdb_state *ks)
+{
+ struct task_struct *thread;
+ void *local_debuggerinfo;
+ int i;
+
+ thread = kgdb_usethread;
+ if (!thread) {
+ thread = kgdb_info[ks->cpu].task;
+ local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
+ } else {
+ local_debuggerinfo = NULL;
+ for_each_online_cpu(i) {
+ /*
+ * Try to find the task on some other
+ * or possibly this node if we do not
+ * find the matching task then we try
+ * to approximate the results.
+ */
+ if (thread == kgdb_info[i].task)
+ local_debuggerinfo = kgdb_info[i].debuggerinfo;
+ }
+ }
+
+ /*
+ * All threads that don't have debuggerinfo should be
+ * in schedule() sleeping, since all other CPUs
+ * are in kgdb_wait, and thus have debuggerinfo.
+ */
+ if (local_debuggerinfo) {
+ pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
+ } else {
+ /*
+ * Pull stuff saved during switch_to; nothing
+ * else is accessible (or even particularly
+ * relevant).
+ *
+ * This should be enough for a stack trace.
+ */
+ sleeping_thread_to_gdb_regs(gdb_regs, thread);
+ }
+ kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
+}
+
+/* Handle the 'G' set registers request */
+static void gdb_cmd_setregs(struct kgdb_state *ks)
+{
+ kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
+
+ if (kgdb_usethread && kgdb_usethread != current) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ } else {
+ gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
+ strcpy(remcom_out_buffer, "OK");
+ }
+}
+
+/* Handle the 'm' memory read bytes */
+static void gdb_cmd_memread(struct kgdb_state *ks)
+{
+ char *ptr = &remcom_in_buffer[1];
+ unsigned long length;
+ unsigned long addr;
+ int err;
+
+ if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
+ kgdb_hex2long(&ptr, &length) > 0) {
+ err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ } else {
+ error_packet(remcom_out_buffer, -EINVAL);
+ }
+}
+
+/* Handle the 'M' memory write bytes */
+static void gdb_cmd_memwrite(struct kgdb_state *ks)
+{
+ int err = write_mem_msg(0);
+
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ else
+ strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'X' memory binary write bytes */
+static void gdb_cmd_binwrite(struct kgdb_state *ks)
+{
+ int err = write_mem_msg(1);
+
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ else
+ strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'D' or 'k', detach or kill packets */
+static void gdb_cmd_detachkill(struct kgdb_state *ks)
+{
+ int error;
+
+ /* The detach case */
+ if (remcom_in_buffer[0] == 'D') {
+ error = remove_all_break();
+ if (error < 0) {
+ error_packet(remcom_out_buffer, error);
+ } else {
+ strcpy(remcom_out_buffer, "OK");
+ kgdb_connected = 0;
+ }
+ put_packet(remcom_out_buffer);
+ } else {
+ /*
+ * Assume the kill case, with no exit code checking,
+ * trying to force detach the debugger:
+ */
+ remove_all_break();
+ kgdb_connected = 0;
+ }
+}
+
+/* Handle the 'R' reboot packets */
+static int gdb_cmd_reboot(struct kgdb_state *ks)
+{
+ /* For now, only honor R0 */
+ if (strcmp(remcom_in_buffer, "R0") == 0) {
+ printk(KERN_CRIT "Executing emergency reboot\n");
+ strcpy(remcom_out_buffer, "OK");
+ put_packet(remcom_out_buffer);
+
+ /*
+ * Execution should not return from
+ * machine_emergency_restart()
+ */
+ machine_emergency_restart();
+ kgdb_connected = 0;
+
+ return 1;
+ }
+ return 0;
+}
+
+/* Handle the 'q' query packets */
+static void gdb_cmd_query(struct kgdb_state *ks)
+{
+ struct task_struct *g;
+ struct task_struct *p;
+ unsigned char thref[8];
+ char *ptr;
+ int i;
+ int cpu;
+ int finished = 0;
+
+ switch (remcom_in_buffer[1]) {
+ case 's':
+ case 'f':
+ if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+
+ i = 0;
+ remcom_out_buffer[0] = 'm';
+ ptr = remcom_out_buffer + 1;
+ if (remcom_in_buffer[1] == 'f') {
+ /* Each cpu is a shadow thread */
+ for_each_online_cpu(cpu) {
+ ks->thr_query = 0;
+ int_to_threadref(thref, -cpu - 2);
+ pack_threadid(ptr, thref);
+ ptr += BUF_THREAD_ID_SIZE;
+ *(ptr++) = ',';
+ i++;
+ }
+ }
+
+ do_each_thread(g, p) {
+ if (i >= ks->thr_query && !finished) {
+ int_to_threadref(thref, p->pid);
+ pack_threadid(ptr, thref);
+ ptr += BUF_THREAD_ID_SIZE;
+ *(ptr++) = ',';
+ ks->thr_query++;
+ if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
+ finished = 1;
+ }
+ i++;
+ } while_each_thread(g, p);
+
+ *(--ptr) = '\0';
+ break;
+
+ case 'C':
+ /* Current thread id */
+ strcpy(remcom_out_buffer, "QC");
+ ks->threadid = shadow_pid(current->pid);
+ int_to_threadref(thref, ks->threadid);
+ pack_threadid(remcom_out_buffer + 2, thref);
+ break;
+ case 'T':
+ if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ ks->threadid = 0;
+ ptr = remcom_in_buffer + 17;
+ kgdb_hex2long(&ptr, &ks->threadid);
+ if (!getthread(ks->linux_regs, ks->threadid)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ if ((int)ks->threadid > 0) {
+ kgdb_mem2hex(getthread(ks->linux_regs,
+ ks->threadid)->comm,
+ remcom_out_buffer, 16);
+ } else {
+ static char tmpstr[23 + BUF_THREAD_ID_SIZE];
+
+ sprintf(tmpstr, "shadowCPU%d",
+ (int)(-ks->threadid - 2));
+ kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
+ }
+ break;
+ }
+}
+
+/* Handle the 'H' task query packets */
+static void gdb_cmd_task(struct kgdb_state *ks)
+{
+ struct task_struct *thread;
+ char *ptr;
+
+ switch (remcom_in_buffer[1]) {
+ case 'g':
+ ptr = &remcom_in_buffer[2];
+ kgdb_hex2long(&ptr, &ks->threadid);
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (!thread && ks->threadid > 0) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ kgdb_usethread = thread;
+ ks->kgdb_usethreadid = ks->threadid;
+ strcpy(remcom_out_buffer, "OK");
+ break;
+ case 'c':
+ ptr = &remcom_in_buffer[2];
+ kgdb_hex2long(&ptr, &ks->threadid);
+ if (!ks->threadid) {
+ kgdb_contthread = NULL;
+ } else {
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (!thread && ks->threadid > 0) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ kgdb_contthread = thread;
+ }
+ strcpy(remcom_out_buffer, "OK");
+ break;
+ }
+}
+
+/* Handle the 'T' thread query packets */
+static void gdb_cmd_thread(struct kgdb_state *ks)
+{
+ char *ptr = &remcom_in_buffer[1];
+ struct task_struct *thread;
+
+ kgdb_hex2long(&ptr, &ks->threadid);
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (thread)
+ strcpy(remcom_out_buffer, "OK");
+ else
+ error_packet(remcom_out_buffer, -EINVAL);
+}
+
+/* Handle the 'z' or 'Z' breakpoint remove or set packets */
+static void gdb_cmd_break(struct kgdb_state *ks)
+{
+ /*
+ * Since GDB-5.3, it's been drafted that '0' is a software
+ * breakpoint, '1' is a hardware breakpoint, so let's do that.
+ */
+ char *bpt_type = &remcom_in_buffer[1];
+ char *ptr = &remcom_in_buffer[2];
+ unsigned long addr;
+ unsigned long length;
+ int error = 0;
+
+ if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
+ /* Unsupported */
+ if (*bpt_type > '4')
+ return;
+ } else {
+ if (*bpt_type != '0' && *bpt_type != '1')
+ /* Unsupported. */
+ return;
+ }
+
+ /*
+ * Test if this is a hardware breakpoint, and
+ * if we support it:
+ */
+ if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
+ /* Unsupported. */
+ return;
+
+ if (*(ptr++) != ',') {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+ if (!kgdb_hex2long(&ptr, &addr)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+ if (*(ptr++) != ',' ||
+ !kgdb_hex2long(&ptr, &length)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+
+ if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
+ error = kgdb_set_sw_break(addr);
+ else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
+ error = kgdb_remove_sw_break(addr);
+ else if (remcom_in_buffer[0] == 'Z')
+ error = arch_kgdb_ops.set_hw_breakpoint(addr,
+ (int)length, *bpt_type - '0');
+ else if (remcom_in_buffer[0] == 'z')
+ error = arch_kgdb_ops.remove_hw_breakpoint(addr,
+ (int) length, *bpt_type - '0');
+
+ if (error == 0)
+ strcpy(remcom_out_buffer, "OK");
+ else
+ error_packet(remcom_out_buffer, error);
+}
+
+/* Handle the 'C' signal / exception passing packets */
+static int gdb_cmd_exception_pass(struct kgdb_state *ks)
+{
+ /* C09 == pass exception
+ * C15 == detach kgdb, pass exception
+ */
+ if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
+
+ ks->pass_exception = 1;
+ remcom_in_buffer[0] = 'c';
+
+ } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
+
+ ks->pass_exception = 1;
+ remcom_in_buffer[0] = 'D';
+ remove_all_break();
+ kgdb_connected = 0;
+ return 1;
+
+ } else {
+ kgdb_msg_write("KGDB only knows signal 9 (pass)"
+ " and 15 (pass and disconnect)\n"
+ "Executing a continue without signal passing\n", 0);
+ remcom_in_buffer[0] = 'c';
+ }
+
+ /* Indicate fall through */
+ return -1;
+}
+
+/*
+ * This function performs all gdbserial command procesing
+ */
+static int gdb_serial_stub(struct kgdb_state *ks)
+{
+ int error = 0;
+ int tmp;
+
+ /* Clear the out buffer. */
+ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+ if (kgdb_connected) {
+ unsigned char thref[8];
+ char *ptr;
+
+ /* Reply to host that an exception has occurred */
+ ptr = remcom_out_buffer;
+ *ptr++ = 'T';
+ ptr = pack_hex_byte(ptr, ks->signo);
+ ptr += strlen(strcpy(ptr, "thread:"));
+ int_to_threadref(thref, shadow_pid(current->pid));
+ ptr = pack_threadid(ptr, thref);
+ *ptr++ = ';';
+ put_packet(remcom_out_buffer);
+ }
+
+ kgdb_usethread = kgdb_info[ks->cpu].task;
+ ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
+ ks->pass_exception = 0;
+
+ while (1) {
+ error = 0;
+
+ /* Clear the out buffer. */
+ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+ get_packet(remcom_in_buffer);
+
+ switch (remcom_in_buffer[0]) {
+ case '?': /* gdbserial status */
+ gdb_cmd_status(ks);
+ break;
+ case 'g': /* return the value of the CPU registers */
+ gdb_cmd_getregs(ks);
+ break;
+ case 'G': /* set the value of the CPU registers - return OK */
+ gdb_cmd_setregs(ks);
+ break;
+ case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
+ gdb_cmd_memread(ks);
+ break;
+ case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+ gdb_cmd_memwrite(ks);
+ break;
+ case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+ gdb_cmd_binwrite(ks);
+ break;
+ /* kill or detach. KGDB should treat this like a
+ * continue.
+ */
+ case 'D': /* Debugger detach */
+ case 'k': /* Debugger detach via kill */
+ gdb_cmd_detachkill(ks);
+ goto default_handle;
+ case 'R': /* Reboot */
+ if (gdb_cmd_reboot(ks))
+ goto default_handle;
+ break;
+ case 'q': /* query command */
+ gdb_cmd_query(ks);
+ break;
+ case 'H': /* task related */
+ gdb_cmd_task(ks);
+ break;
+ case 'T': /* Query thread status */
+ gdb_cmd_thread(ks);
+ break;
+ case 'z': /* Break point remove */
+ case 'Z': /* Break point set */
+ gdb_cmd_break(ks);
+ break;
+ case 'C': /* Exception passing */
+ tmp = gdb_cmd_exception_pass(ks);
+ if (tmp > 0)
+ goto default_handle;
+ if (tmp == 0)
+ break;
+ /* Fall through on tmp < 0 */
+ case 'c': /* Continue packet */
+ case 's': /* Single step packet */
+ if (kgdb_contthread && kgdb_contthread != current) {
+ /* Can't switch threads in kgdb */
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ kgdb_activate_sw_breakpoints();
+ /* Fall through to default processing */
+ default:
+default_handle:
+ error = kgdb_arch_handle_exception(ks->ex_vector,
+ ks->signo,
+ ks->err_code,
+ remcom_in_buffer,
+ remcom_out_buffer,
+ ks->linux_regs);
+ /*
+ * Leave cmd processing on error, detach,
+ * kill, continue, or single step.
+ */
+ if (error >= 0 || remcom_in_buffer[0] == 'D' ||
+ remcom_in_buffer[0] == 'k') {
+ error = 0;
+ goto kgdb_exit;
+ }
+
+ }
+
+ /* reply to the request */
+ put_packet(remcom_out_buffer);
+ }
+
+kgdb_exit:
+ if (ks->pass_exception)
+ error = 1;
+ return error;
+}
+
+static int kgdb_reenter_check(struct kgdb_state *ks)
+{
+ unsigned long addr;
+
+ if (atomic_read(&kgdb_active) != raw_smp_processor_id())
+ return 0;
+
+ /* Panic on recursive debugger calls: */
+ exception_level++;
+ addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
+ kgdb_deactivate_sw_breakpoints();
+
+ /*
+ * If the break point removed ok at the place exception
+ * occurred, try to recover and print a warning to the end
+ * user because the user planted a breakpoint in a place that
+ * KGDB needs in order to function.
+ */
+ if (kgdb_remove_sw_break(addr) == 0) {
+ exception_level = 0;
+ kgdb_skipexception(ks->ex_vector, ks->linux_regs);
+ kgdb_activate_sw_breakpoints();
+ printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n",
+ addr);
+ WARN_ON_ONCE(1);
+
+ return 1;
+ }
+ remove_all_break();
+ kgdb_skipexception(ks->ex_vector, ks->linux_regs);
+
+ if (exception_level > 1) {
+ dump_stack();
+ panic("Recursive entry to debugger");
+ }
+
+ printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
+ dump_stack();
+ panic("Recursive entry to debugger");
+
+ return 1;
+}
+
+/*
+ * kgdb_handle_exception() - main entry point from a kernel exception
+ *
+ * Locking hierarchy:
+ * interface locks, if any (begin_session)
+ * kgdb lock (kgdb_active)
+ */
+int
+kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
+{
+ struct kgdb_state kgdb_var;
+ struct kgdb_state *ks = &kgdb_var;
+ unsigned long flags;
+ int sstep_tries = 100;
+ int error = 0;
+ int i, cpu;
+
+ ks->cpu = raw_smp_processor_id();
+ ks->ex_vector = evector;
+ ks->signo = signo;
+ ks->ex_vector = evector;
+ ks->err_code = ecode;
+ ks->kgdb_usethreadid = 0;
+ ks->linux_regs = regs;
+
+ if (kgdb_reenter_check(ks))
+ return 0; /* Ouch, double exception ! */
+
+acquirelock:
+ /*
+ * Interrupts will be restored by the 'trap return' code, except when
+ * single stepping.
+ */
+ local_irq_save(flags);
+
+ cpu = raw_smp_processor_id();
+
+ /*
+ * Acquire the kgdb_active lock:
+ */
+ while (atomic_cmpxchg(&kgdb_active, -1, cpu) != -1)
+ cpu_relax();
+
+ /*
+ * For single stepping, try to only enter on the processor
+ * that was single stepping. To gaurd against a deadlock, the
+ * kernel will only try for the value of sstep_tries before
+ * giving up and continuing on.
+ */
+ if (atomic_read(&kgdb_cpu_doing_single_step) != -1 &&
+ (kgdb_info[cpu].task &&
+ kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
+ atomic_set(&kgdb_active, -1);
+ touch_softlockup_watchdog_sync();
+ clocksource_touch_watchdog();
+ local_irq_restore(flags);
+
+ goto acquirelock;
+ }
+
+ if (!kgdb_io_ready(1)) {
+ error = 1;
+ goto kgdb_restore; /* No I/O connection, so resume the system */
+ }
+
+ /*
+ * Don't enter if we have hit a removed breakpoint.
+ */
+ if (kgdb_skipexception(ks->ex_vector, ks->linux_regs))
+ goto kgdb_restore;
+
+ /* Call the I/O driver's pre_exception routine */
+ if (kgdb_io_ops->pre_exception)
+ kgdb_io_ops->pre_exception();
+
+ kgdb_info[ks->cpu].debuggerinfo = ks->linux_regs;
+ kgdb_info[ks->cpu].task = current;
+
+ kgdb_disable_hw_debug(ks->linux_regs);
+
+ /*
+ * Get the passive CPU lock which will hold all the non-primary
+ * CPU in a spin state while the debugger is active
+ */
+ if (!kgdb_single_step) {
+ for (i = 0; i < NR_CPUS; i++)
+ atomic_set(&passive_cpu_wait[i], 1);
+ }
+
+ /*
+ * spin_lock code is good enough as a barrier so we don't
+ * need one here:
+ */
+ atomic_set(&cpu_in_kgdb[ks->cpu], 1);
+
+#ifdef CONFIG_SMP
+ /* Signal the other CPUs to enter kgdb_wait() */
+ if ((!kgdb_single_step) && kgdb_do_roundup)
+ kgdb_roundup_cpus(flags);
+#endif
+
+ /*
+ * Wait for the other CPUs to be notified and be waiting for us:
+ */
+ for_each_online_cpu(i) {
+ while (!atomic_read(&cpu_in_kgdb[i]))
+ cpu_relax();
+ }
+
+ /*
+ * At this point the primary processor is completely
+ * in the debugger and all secondary CPUs are quiescent
+ */
+ kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
+ kgdb_deactivate_sw_breakpoints();
+ kgdb_single_step = 0;
+ kgdb_contthread = current;
+ exception_level = 0;
+
+ /* Talk to debugger with gdbserial protocol */
+ error = gdb_serial_stub(ks);
+
+ /* Call the I/O driver's post_exception routine */
+ if (kgdb_io_ops->post_exception)
+ kgdb_io_ops->post_exception();
+
+ kgdb_info[ks->cpu].debuggerinfo = NULL;
+ kgdb_info[ks->cpu].task = NULL;
+ atomic_set(&cpu_in_kgdb[ks->cpu], 0);
+
+ if (!kgdb_single_step) {
+ for (i = NR_CPUS-1; i >= 0; i--)
+ atomic_set(&passive_cpu_wait[i], 0);
+ /*
+ * Wait till all the CPUs have quit
+ * from the debugger.
+ */
+ for_each_online_cpu(i) {
+ while (atomic_read(&cpu_in_kgdb[i]))
+ cpu_relax();
+ }
+ }
+
+kgdb_restore:
+ if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
+ int sstep_cpu = atomic_read(&kgdb_cpu_doing_single_step);
+ if (kgdb_info[sstep_cpu].task)
+ kgdb_sstep_pid = kgdb_info[sstep_cpu].task->pid;
+ else
+ kgdb_sstep_pid = 0;
+ }
+ /* Free kgdb_active */
+ atomic_set(&kgdb_active, -1);
+ touch_softlockup_watchdog_sync();
+ clocksource_touch_watchdog();
+ local_irq_restore(flags);
+
+ return error;
+}
+
+int kgdb_nmicallback(int cpu, void *regs)
+{
+#ifdef CONFIG_SMP
+ if (!atomic_read(&cpu_in_kgdb[cpu]) &&
+ atomic_read(&kgdb_active) != cpu &&
+ atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)])) {
+ kgdb_wait((struct pt_regs *)regs);
+ return 0;
+ }
+#endif
+ return 1;
+}
+
+static void kgdb_console_write(struct console *co, const char *s,
+ unsigned count)
+{
+ unsigned long flags;
+
+ /* If we're debugging, or KGDB has not connected, don't try
+ * and print. */
+ if (!kgdb_connected || atomic_read(&kgdb_active) != -1)
+ return;
+
+ local_irq_save(flags);
+ kgdb_msg_write(s, count);
+ local_irq_restore(flags);
+}
+
+static struct console kgdbcons = {
+ .name = "kgdb",
+ .write = kgdb_console_write,
+ .flags = CON_PRINTBUFFER | CON_ENABLED,
+ .index = -1,
+};
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static void sysrq_handle_gdb(int key, struct tty_struct *tty)
+{
+ if (!kgdb_io_ops) {
+ printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
+ return;
+ }
+ if (!kgdb_connected)
+ printk(KERN_CRIT "Entering KGDB\n");
+
+ kgdb_breakpoint();
+}
+
+static struct sysrq_key_op sysrq_gdb_op = {
+ .handler = sysrq_handle_gdb,
+ .help_msg = "debug(G)",
+ .action_msg = "DEBUG",
+};
+#endif
+
+static void kgdb_register_callbacks(void)
+{
+ if (!kgdb_io_module_registered) {
+ kgdb_io_module_registered = 1;
+ kgdb_arch_init();
+#ifdef CONFIG_MAGIC_SYSRQ
+ register_sysrq_key('g', &sysrq_gdb_op);
+#endif
+ if (kgdb_use_con && !kgdb_con_registered) {
+ register_console(&kgdbcons);
+ kgdb_con_registered = 1;
+ }
+ }
+}
+
+static void kgdb_unregister_callbacks(void)
+{
+ /*
+ * When this routine is called KGDB should unregister from the
+ * panic handler and clean up, making sure it is not handling any
+ * break exceptions at the time.
+ */
+ if (kgdb_io_module_registered) {
+ kgdb_io_module_registered = 0;
+ kgdb_arch_exit();
+#ifdef CONFIG_MAGIC_SYSRQ
+ unregister_sysrq_key('g', &sysrq_gdb_op);
+#endif
+ if (kgdb_con_registered) {
+ unregister_console(&kgdbcons);
+ kgdb_con_registered = 0;
+ }
+ }
+}
+
+static void kgdb_initial_breakpoint(void)
+{
+ kgdb_break_asap = 0;
+
+ printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n");
+ kgdb_breakpoint();
+}
+
+/**
+ * kgdb_register_io_module - register KGDB IO module
+ * @new_kgdb_io_ops: the io ops vector
+ *
+ * Register it with the KGDB core.
+ */
+int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops)
+{
+ int err;
+
+ spin_lock(&kgdb_registration_lock);
+
+ if (kgdb_io_ops) {
+ spin_unlock(&kgdb_registration_lock);
+
+ printk(KERN_ERR "kgdb: Another I/O driver is already "
+ "registered with KGDB.\n");
+ return -EBUSY;
+ }
+
+ if (new_kgdb_io_ops->init) {
+ err = new_kgdb_io_ops->init();
+ if (err) {
+ spin_unlock(&kgdb_registration_lock);
+ return err;
+ }
+ }
+
+ kgdb_io_ops = new_kgdb_io_ops;
+
+ spin_unlock(&kgdb_registration_lock);
+
+ printk(KERN_INFO "kgdb: Registered I/O driver %s.\n",
+ new_kgdb_io_ops->name);
+
+ /* Arm KGDB now. */
+ kgdb_register_callbacks();
+
+ if (kgdb_break_asap)
+ kgdb_initial_breakpoint();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(kgdb_register_io_module);
+
+/**
+ * kkgdb_unregister_io_module - unregister KGDB IO module
+ * @old_kgdb_io_ops: the io ops vector
+ *
+ * Unregister it with the KGDB core.
+ */
+void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops)
+{
+ BUG_ON(kgdb_connected);
+
+ /*
+ * KGDB is no longer able to communicate out, so
+ * unregister our callbacks and reset state.
+ */
+ kgdb_unregister_callbacks();
+
+ spin_lock(&kgdb_registration_lock);
+
+ WARN_ON_ONCE(kgdb_io_ops != old_kgdb_io_ops);
+ kgdb_io_ops = NULL;
+
+ spin_unlock(&kgdb_registration_lock);
+
+ printk(KERN_INFO
+ "kgdb: Unregistered I/O driver %s, debugger disabled.\n",
+ old_kgdb_io_ops->name);
+}
+EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
+
+/**
+ * kgdb_breakpoint - generate breakpoint exception
+ *
+ * This function will generate a breakpoint exception. It is used at the
+ * beginning of a program to sync up with a debugger and can be used
+ * otherwise as a quick means to stop program execution and "break" into
+ * the debugger.
+ */
+void kgdb_breakpoint(void)
+{
+ atomic_set(&kgdb_setting_breakpoint, 1);
+ wmb(); /* Sync point before breakpoint */
+ arch_kgdb_breakpoint();
+ wmb(); /* Sync point after breakpoint */
+ atomic_set(&kgdb_setting_breakpoint, 0);
+}
+EXPORT_SYMBOL_GPL(kgdb_breakpoint);
+
+static int __init opt_kgdb_wait(char *str)
+{
+ kgdb_break_asap = 1;
+
+ if (kgdb_io_module_registered)
+ kgdb_initial_breakpoint();
+
+ return 0;
+}
+
+early_param("kgdbwait", opt_kgdb_wait);
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
deleted file mode 100644
index 761fdd2..0000000
--- a/kernel/kgdb.c
+++ /dev/null
@@ -1,1763 +0,0 @@
-/*
- * KGDB stub.
- *
- * Maintainer: Jason Wessel <jason.wessel@windriver.com>
- *
- * Copyright (C) 2000-2001 VERITAS Software Corporation.
- * Copyright (C) 2002-2004 Timesys Corporation
- * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
- * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
- * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
- * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
- * Copyright (C) 2005-2008 Wind River Systems, Inc.
- * Copyright (C) 2007 MontaVista Software, Inc.
- * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- *
- * Contributors at various stages not listed above:
- * Jason Wessel ( jason.wessel@windriver.com )
- * George Anzinger <george@mvista.com>
- * Anurekh Saxena (anurekh.saxena@timesys.com)
- * Lake Stevens Instrument Division (Glenn Engel)
- * Jim Kingdon, Cygnus Support.
- *
- * Original KGDB stub: David Grothe <dave@gcom.com>,
- * Tigran Aivazian <tigran@sco.com>
- *
- * This file is licensed under the terms of the GNU General Public License
- * version 2. This program is licensed "as is" without any warranty of any
- * kind, whether express or implied.
- */
-#include <linux/pid_namespace.h>
-#include <linux/clocksource.h>
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/console.h>
-#include <linux/threads.h>
-#include <linux/uaccess.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/ptrace.h>
-#include <linux/reboot.h>
-#include <linux/string.h>
-#include <linux/delay.h>
-#include <linux/sched.h>
-#include <linux/sysrq.h>
-#include <linux/init.h>
-#include <linux/kgdb.h>
-#include <linux/pid.h>
-#include <linux/smp.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-#include <asm/byteorder.h>
-#include <asm/atomic.h>
-#include <asm/system.h>
-#include <asm/unaligned.h>
-
-static int kgdb_break_asap;
-
-#define KGDB_MAX_THREAD_QUERY 17
-struct kgdb_state {
- int ex_vector;
- int signo;
- int err_code;
- int cpu;
- int pass_exception;
- unsigned long thr_query;
- unsigned long threadid;
- long kgdb_usethreadid;
- struct pt_regs *linux_regs;
-};
-
-static struct debuggerinfo_struct {
- void *debuggerinfo;
- struct task_struct *task;
-} kgdb_info[NR_CPUS];
-
-/**
- * kgdb_connected - Is a host GDB connected to us?
- */
-int kgdb_connected;
-EXPORT_SYMBOL_GPL(kgdb_connected);
-
-/* All the KGDB handlers are installed */
-static int kgdb_io_module_registered;
-
-/* Guard for recursive entry */
-static int exception_level;
-
-static struct kgdb_io *kgdb_io_ops;
-static DEFINE_SPINLOCK(kgdb_registration_lock);
-
-/* kgdb console driver is loaded */
-static int kgdb_con_registered;
-/* determine if kgdb console output should be used */
-static int kgdb_use_con;
-
-static int __init opt_kgdb_con(char *str)
-{
- kgdb_use_con = 1;
- return 0;
-}
-
-early_param("kgdbcon", opt_kgdb_con);
-
-module_param(kgdb_use_con, int, 0644);
-
-/*
- * Holds information about breakpoints in a kernel. These breakpoints are
- * added and removed by gdb.
- */
-static struct kgdb_bkpt kgdb_break[KGDB_MAX_BREAKPOINTS] = {
- [0 ... KGDB_MAX_BREAKPOINTS-1] = { .state = BP_UNDEFINED }
-};
-
-/*
- * The CPU# of the active CPU, or -1 if none:
- */
-atomic_t kgdb_active = ATOMIC_INIT(-1);
-
-/*
- * We use NR_CPUs not PERCPU, in case kgdb is used to debug early
- * bootup code (which might not have percpu set up yet):
- */
-static atomic_t passive_cpu_wait[NR_CPUS];
-static atomic_t cpu_in_kgdb[NR_CPUS];
-atomic_t kgdb_setting_breakpoint;
-
-struct task_struct *kgdb_usethread;
-struct task_struct *kgdb_contthread;
-
-int kgdb_single_step;
-pid_t kgdb_sstep_pid;
-
-/* Our I/O buffers. */
-static char remcom_in_buffer[BUFMAX];
-static char remcom_out_buffer[BUFMAX];
-
-/* Storage for the registers, in GDB format. */
-static unsigned long gdb_regs[(NUMREGBYTES +
- sizeof(unsigned long) - 1) /
- sizeof(unsigned long)];
-
-/* to keep track of the CPU which is doing the single stepping*/
-atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
-
-/*
- * If you are debugging a problem where roundup (the collection of
- * all other CPUs) is a problem [this should be extremely rare],
- * then use the nokgdbroundup option to avoid roundup. In that case
- * the other CPUs might interfere with your debugging context, so
- * use this with care:
- */
-static int kgdb_do_roundup = 1;
-
-static int __init opt_nokgdbroundup(char *str)
-{
- kgdb_do_roundup = 0;
-
- return 0;
-}
-
-early_param("nokgdbroundup", opt_nokgdbroundup);
-
-/*
- * Finally, some KGDB code :-)
- */
-
-/*
- * Weak aliases for breakpoint management,
- * can be overriden by architectures when needed:
- */
-int __weak kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr)
-{
- int err;
-
- err = probe_kernel_read(saved_instr, (char *)addr, BREAK_INSTR_SIZE);
- if (err)
- return err;
-
- return probe_kernel_write((char *)addr, arch_kgdb_ops.gdb_bpt_instr,
- BREAK_INSTR_SIZE);
-}
-
-int __weak kgdb_arch_remove_breakpoint(unsigned long addr, char *bundle)
-{
- return probe_kernel_write((char *)addr,
- (char *)bundle, BREAK_INSTR_SIZE);
-}
-
-int __weak kgdb_validate_break_address(unsigned long addr)
-{
- char tmp_variable[BREAK_INSTR_SIZE];
- int err;
- /* Validate setting the breakpoint and then removing it. In the
- * remove fails, the kernel needs to emit a bad message because we
- * are deep trouble not being able to put things back the way we
- * found them.
- */
- err = kgdb_arch_set_breakpoint(addr, tmp_variable);
- if (err)
- return err;
- err = kgdb_arch_remove_breakpoint(addr, tmp_variable);
- if (err)
- printk(KERN_ERR "KGDB: Critical breakpoint error, kernel "
- "memory destroyed at: %lx", addr);
- return err;
-}
-
-unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs)
-{
- return instruction_pointer(regs);
-}
-
-int __weak kgdb_arch_init(void)
-{
- return 0;
-}
-
-int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
-{
- return 0;
-}
-
-void __weak
-kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
-{
- return;
-}
-
-/**
- * kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
- * @regs: Current &struct pt_regs.
- *
- * This function will be called if the particular architecture must
- * disable hardware debugging while it is processing gdb packets or
- * handling exception.
- */
-void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
-{
-}
-
-/*
- * GDB remote protocol parser:
- */
-
-static int hex(char ch)
-{
- if ((ch >= 'a') && (ch <= 'f'))
- return ch - 'a' + 10;
- if ((ch >= '0') && (ch <= '9'))
- return ch - '0';
- if ((ch >= 'A') && (ch <= 'F'))
- return ch - 'A' + 10;
- return -1;
-}
-
-/* scan for the sequence $<data>#<checksum> */
-static void get_packet(char *buffer)
-{
- unsigned char checksum;
- unsigned char xmitcsum;
- int count;
- char ch;
-
- do {
- /*
- * Spin and wait around for the start character, ignore all
- * other characters:
- */
- while ((ch = (kgdb_io_ops->read_char())) != '$')
- /* nothing */;
-
- kgdb_connected = 1;
- checksum = 0;
- xmitcsum = -1;
-
- count = 0;
-
- /*
- * now, read until a # or end of buffer is found:
- */
- while (count < (BUFMAX - 1)) {
- ch = kgdb_io_ops->read_char();
- if (ch == '#')
- break;
- checksum = checksum + ch;
- buffer[count] = ch;
- count = count + 1;
- }
- buffer[count] = 0;
-
- if (ch == '#') {
- xmitcsum = hex(kgdb_io_ops->read_char()) << 4;
- xmitcsum += hex(kgdb_io_ops->read_char());
-
- if (checksum != xmitcsum)
- /* failed checksum */
- kgdb_io_ops->write_char('-');
- else
- /* successful transfer */
- kgdb_io_ops->write_char('+');
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
- }
- } while (checksum != xmitcsum);
-}
-
-/*
- * Send the packet in buffer.
- * Check for gdb connection if asked for.
- */
-static void put_packet(char *buffer)
-{
- unsigned char checksum;
- int count;
- char ch;
-
- /*
- * $<packet info>#<checksum>.
- */
- while (1) {
- kgdb_io_ops->write_char('$');
- checksum = 0;
- count = 0;
-
- while ((ch = buffer[count])) {
- kgdb_io_ops->write_char(ch);
- checksum += ch;
- count++;
- }
-
- kgdb_io_ops->write_char('#');
- kgdb_io_ops->write_char(hex_asc_hi(checksum));
- kgdb_io_ops->write_char(hex_asc_lo(checksum));
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
-
- /* Now see what we get in reply. */
- ch = kgdb_io_ops->read_char();
-
- if (ch == 3)
- ch = kgdb_io_ops->read_char();
-
- /* If we get an ACK, we are done. */
- if (ch == '+')
- return;
-
- /*
- * If we get the start of another packet, this means
- * that GDB is attempting to reconnect. We will NAK
- * the packet being sent, and stop trying to send this
- * packet.
- */
- if (ch == '$') {
- kgdb_io_ops->write_char('-');
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
- return;
- }
- }
-}
-
-/*
- * Convert the memory pointed to by mem into hex, placing result in buf.
- * Return a pointer to the last char put in buf (null). May return an error.
- */
-int kgdb_mem2hex(char *mem, char *buf, int count)
-{
- char *tmp;
- int err;
-
- /*
- * We use the upper half of buf as an intermediate buffer for the
- * raw memory copy. Hex conversion will work against this one.
- */
- tmp = buf + count;
-
- err = probe_kernel_read(tmp, mem, count);
- if (!err) {
- while (count > 0) {
- buf = pack_hex_byte(buf, *tmp);
- tmp++;
- count--;
- }
-
- *buf = 0;
- }
-
- return err;
-}
-
-/*
- * Copy the binary array pointed to by buf into mem. Fix $, #, and
- * 0x7d escaped with 0x7d. Return a pointer to the character after
- * the last byte written.
- */
-static int kgdb_ebin2mem(char *buf, char *mem, int count)
-{
- int err = 0;
- char c;
-
- while (count-- > 0) {
- c = *buf++;
- if (c == 0x7d)
- c = *buf++ ^ 0x20;
-
- err = probe_kernel_write(mem, &c, 1);
- if (err)
- break;
-
- mem++;
- }
-
- return err;
-}
-
-/*
- * Convert the hex array pointed to by buf into binary to be placed in mem.
- * Return a pointer to the character AFTER the last byte written.
- * May return an error.
- */
-int kgdb_hex2mem(char *buf, char *mem, int count)
-{
- char *tmp_raw;
- char *tmp_hex;
-
- /*
- * We use the upper half of buf as an intermediate buffer for the
- * raw memory that is converted from hex.
- */
- tmp_raw = buf + count * 2;
-
- tmp_hex = tmp_raw - 1;
- while (tmp_hex >= buf) {
- tmp_raw--;
- *tmp_raw = hex(*tmp_hex--);
- *tmp_raw |= hex(*tmp_hex--) << 4;
- }
-
- return probe_kernel_write(mem, tmp_raw, count);
-}
-
-/*
- * While we find nice hex chars, build a long_val.
- * Return number of chars processed.
- */
-int kgdb_hex2long(char **ptr, unsigned long *long_val)
-{
- int hex_val;
- int num = 0;
- int negate = 0;
-
- *long_val = 0;
-
- if (**ptr == '-') {
- negate = 1;
- (*ptr)++;
- }
- while (**ptr) {
- hex_val = hex(**ptr);
- if (hex_val < 0)
- break;
-
- *long_val = (*long_val << 4) | hex_val;
- num++;
- (*ptr)++;
- }
-
- if (negate)
- *long_val = -*long_val;
-
- return num;
-}
-
-/* Write memory due to an 'M' or 'X' packet. */
-static int write_mem_msg(int binary)
-{
- char *ptr = &remcom_in_buffer[1];
- unsigned long addr;
- unsigned long length;
- int err;
-
- if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
- kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
- if (binary)
- err = kgdb_ebin2mem(ptr, (char *)addr, length);
- else
- err = kgdb_hex2mem(ptr, (char *)addr, length);
- if (err)
- return err;
- if (CACHE_FLUSH_IS_SAFE)
- flush_icache_range(addr, addr + length);
- return 0;
- }
-
- return -EINVAL;
-}
-
-static void error_packet(char *pkt, int error)
-{
- error = -error;
- pkt[0] = 'E';
- pkt[1] = hex_asc[(error / 10)];
- pkt[2] = hex_asc[(error % 10)];
- pkt[3] = '\0';
-}
-
-/*
- * Thread ID accessors. We represent a flat TID space to GDB, where
- * the per CPU idle threads (which under Linux all have PID 0) are
- * remapped to negative TIDs.
- */
-
-#define BUF_THREAD_ID_SIZE 16
-
-static char *pack_threadid(char *pkt, unsigned char *id)
-{
- char *limit;
-
- limit = pkt + BUF_THREAD_ID_SIZE;
- while (pkt < limit)
- pkt = pack_hex_byte(pkt, *id++);
-
- return pkt;
-}
-
-static void int_to_threadref(unsigned char *id, int value)
-{
- unsigned char *scan;
- int i = 4;
-
- scan = (unsigned char *)id;
- while (i--)
- *scan++ = 0;
- put_unaligned_be32(value, scan);
-}
-
-static struct task_struct *getthread(struct pt_regs *regs, int tid)
-{
- /*
- * Non-positive TIDs are remapped to the cpu shadow information
- */
- if (tid == 0 || tid == -1)
- tid = -atomic_read(&kgdb_active) - 2;
- if (tid < -1 && tid > -NR_CPUS - 2) {
- if (kgdb_info[-tid - 2].task)
- return kgdb_info[-tid - 2].task;
- else
- return idle_task(-tid - 2);
- }
- if (tid <= 0) {
- printk(KERN_ERR "KGDB: Internal thread select error\n");
- dump_stack();
- return NULL;
- }
-
- /*
- * find_task_by_pid_ns() does not take the tasklist lock anymore
- * but is nicely RCU locked - hence is a pretty resilient
- * thing to use:
- */
- return find_task_by_pid_ns(tid, &init_pid_ns);
-}
-
-/*
- * CPU debug state control:
- */
-
-#ifdef CONFIG_SMP
-static void kgdb_wait(struct pt_regs *regs)
-{
- unsigned long flags;
- int cpu;
-
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- kgdb_info[cpu].debuggerinfo = regs;
- kgdb_info[cpu].task = current;
- /*
- * Make sure the above info reaches the primary CPU before
- * our cpu_in_kgdb[] flag setting does:
- */
- smp_wmb();
- atomic_set(&cpu_in_kgdb[cpu], 1);
-
- /* Disable any cpu specific hw breakpoints */
- kgdb_disable_hw_debug(regs);
-
- /* Wait till primary CPU is done with debugging */
- while (atomic_read(&passive_cpu_wait[cpu]))
- cpu_relax();
-
- kgdb_info[cpu].debuggerinfo = NULL;
- kgdb_info[cpu].task = NULL;
-
- /* fix up hardware debug registers on local cpu */
- if (arch_kgdb_ops.correct_hw_break)
- arch_kgdb_ops.correct_hw_break();
-
- /* Signal the primary CPU that we are done: */
- atomic_set(&cpu_in_kgdb[cpu], 0);
- touch_softlockup_watchdog_sync();
- clocksource_touch_watchdog();
- local_irq_restore(flags);
-}
-#endif
-
-/*
- * Some architectures need cache flushes when we set/clear a
- * breakpoint:
- */
-static void kgdb_flush_swbreak_addr(unsigned long addr)
-{
- if (!CACHE_FLUSH_IS_SAFE)
- return;
-
- if (current->mm && current->mm->mmap_cache) {
- flush_cache_range(current->mm->mmap_cache,
- addr, addr + BREAK_INSTR_SIZE);
- }
- /* Force flush instruction cache if it was outside the mm */
- flush_icache_range(addr, addr + BREAK_INSTR_SIZE);
-}
-
-/*
- * SW breakpoint management:
- */
-static int kgdb_activate_sw_breakpoints(void)
-{
- unsigned long addr;
- int error;
- int ret = 0;
- int i;
-
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if (kgdb_break[i].state != BP_SET)
- continue;
-
- addr = kgdb_break[i].bpt_addr;
- error = kgdb_arch_set_breakpoint(addr,
- kgdb_break[i].saved_instr);
- if (error) {
- ret = error;
- printk(KERN_INFO "KGDB: BP install failed: %lx", addr);
- continue;
- }
-
- kgdb_flush_swbreak_addr(addr);
- kgdb_break[i].state = BP_ACTIVE;
- }
- return ret;
-}
-
-static int kgdb_set_sw_break(unsigned long addr)
-{
- int err = kgdb_validate_break_address(addr);
- int breakno = -1;
- int i;
-
- if (err)
- return err;
-
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if ((kgdb_break[i].state == BP_SET) &&
- (kgdb_break[i].bpt_addr == addr))
- return -EEXIST;
- }
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if (kgdb_break[i].state == BP_REMOVED &&
- kgdb_break[i].bpt_addr == addr) {
- breakno = i;
- break;
- }
- }
-
- if (breakno == -1) {
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if (kgdb_break[i].state == BP_UNDEFINED) {
- breakno = i;
- break;
- }
- }
- }
-
- if (breakno == -1)
- return -E2BIG;
-
- kgdb_break[breakno].state = BP_SET;
- kgdb_break[breakno].type = BP_BREAKPOINT;
- kgdb_break[breakno].bpt_addr = addr;
-
- return 0;
-}
-
-static int kgdb_deactivate_sw_breakpoints(void)
-{
- unsigned long addr;
- int error;
- int ret = 0;
- int i;
-
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if (kgdb_break[i].state != BP_ACTIVE)
- continue;
- addr = kgdb_break[i].bpt_addr;
- error = kgdb_arch_remove_breakpoint(addr,
- kgdb_break[i].saved_instr);
- if (error) {
- printk(KERN_INFO "KGDB: BP remove failed: %lx\n", addr);
- ret = error;
- }
-
- kgdb_flush_swbreak_addr(addr);
- kgdb_break[i].state = BP_SET;
- }
- return ret;
-}
-
-static int kgdb_remove_sw_break(unsigned long addr)
-{
- int i;
-
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if ((kgdb_break[i].state == BP_SET) &&
- (kgdb_break[i].bpt_addr == addr)) {
- kgdb_break[i].state = BP_REMOVED;
- return 0;
- }
- }
- return -ENOENT;
-}
-
-int kgdb_isremovedbreak(unsigned long addr)
-{
- int i;
-
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if ((kgdb_break[i].state == BP_REMOVED) &&
- (kgdb_break[i].bpt_addr == addr))
- return 1;
- }
- return 0;
-}
-
-static int remove_all_break(void)
-{
- unsigned long addr;
- int error;
- int i;
-
- /* Clear memory breakpoints. */
- for (i = 0; i < KGDB_MAX_BREAKPOINTS; i++) {
- if (kgdb_break[i].state != BP_ACTIVE)
- goto setundefined;
- addr = kgdb_break[i].bpt_addr;
- error = kgdb_arch_remove_breakpoint(addr,
- kgdb_break[i].saved_instr);
- if (error)
- printk(KERN_ERR "KGDB: breakpoint remove failed: %lx\n",
- addr);
-setundefined:
- kgdb_break[i].state = BP_UNDEFINED;
- }
-
- /* Clear hardware breakpoints. */
- if (arch_kgdb_ops.remove_all_hw_break)
- arch_kgdb_ops.remove_all_hw_break();
-
- return 0;
-}
-
-/*
- * Remap normal tasks to their real PID,
- * CPU shadow threads are mapped to -CPU - 2
- */
-static inline int shadow_pid(int realpid)
-{
- if (realpid)
- return realpid;
-
- return -raw_smp_processor_id() - 2;
-}
-
-static char gdbmsgbuf[BUFMAX + 1];
-
-static void kgdb_msg_write(const char *s, int len)
-{
- char *bufptr;
- int wcount;
- int i;
-
- /* 'O'utput */
- gdbmsgbuf[0] = 'O';
-
- /* Fill and send buffers... */
- while (len > 0) {
- bufptr = gdbmsgbuf + 1;
-
- /* Calculate how many this time */
- if ((len << 1) > (BUFMAX - 2))
- wcount = (BUFMAX - 2) >> 1;
- else
- wcount = len;
-
- /* Pack in hex chars */
- for (i = 0; i < wcount; i++)
- bufptr = pack_hex_byte(bufptr, s[i]);
- *bufptr = '\0';
-
- /* Move up */
- s += wcount;
- len -= wcount;
-
- /* Write packet */
- put_packet(gdbmsgbuf);
- }
-}
-
-/*
- * Return true if there is a valid kgdb I/O module. Also if no
- * debugger is attached a message can be printed to the console about
- * waiting for the debugger to attach.
- *
- * The print_wait argument is only to be true when called from inside
- * the core kgdb_handle_exception, because it will wait for the
- * debugger to attach.
- */
-static int kgdb_io_ready(int print_wait)
-{
- if (!kgdb_io_ops)
- return 0;
- if (kgdb_connected)
- return 1;
- if (atomic_read(&kgdb_setting_breakpoint))
- return 1;
- if (print_wait)
- printk(KERN_CRIT "KGDB: Waiting for remote debugger\n");
- return 1;
-}
-
-/*
- * All the functions that start with gdb_cmd are the various
- * operations to implement the handlers for the gdbserial protocol
- * where KGDB is communicating with an external debugger
- */
-
-/* Handle the '?' status packets */
-static void gdb_cmd_status(struct kgdb_state *ks)
-{
- /*
- * We know that this packet is only sent
- * during initial connect. So to be safe,
- * we clear out our breakpoints now in case
- * GDB is reconnecting.
- */
- remove_all_break();
-
- remcom_out_buffer[0] = 'S';
- pack_hex_byte(&remcom_out_buffer[1], ks->signo);
-}
-
-/* Handle the 'g' get registers request */
-static void gdb_cmd_getregs(struct kgdb_state *ks)
-{
- struct task_struct *thread;
- void *local_debuggerinfo;
- int i;
-
- thread = kgdb_usethread;
- if (!thread) {
- thread = kgdb_info[ks->cpu].task;
- local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
- } else {
- local_debuggerinfo = NULL;
- for_each_online_cpu(i) {
- /*
- * Try to find the task on some other
- * or possibly this node if we do not
- * find the matching task then we try
- * to approximate the results.
- */
- if (thread == kgdb_info[i].task)
- local_debuggerinfo = kgdb_info[i].debuggerinfo;
- }
- }
-
- /*
- * All threads that don't have debuggerinfo should be
- * in schedule() sleeping, since all other CPUs
- * are in kgdb_wait, and thus have debuggerinfo.
- */
- if (local_debuggerinfo) {
- pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
- } else {
- /*
- * Pull stuff saved during switch_to; nothing
- * else is accessible (or even particularly
- * relevant).
- *
- * This should be enough for a stack trace.
- */
- sleeping_thread_to_gdb_regs(gdb_regs, thread);
- }
- kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
-}
-
-/* Handle the 'G' set registers request */
-static void gdb_cmd_setregs(struct kgdb_state *ks)
-{
- kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
-
- if (kgdb_usethread && kgdb_usethread != current) {
- error_packet(remcom_out_buffer, -EINVAL);
- } else {
- gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
- strcpy(remcom_out_buffer, "OK");
- }
-}
-
-/* Handle the 'm' memory read bytes */
-static void gdb_cmd_memread(struct kgdb_state *ks)
-{
- char *ptr = &remcom_in_buffer[1];
- unsigned long length;
- unsigned long addr;
- int err;
-
- if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
- kgdb_hex2long(&ptr, &length) > 0) {
- err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
- if (err)
- error_packet(remcom_out_buffer, err);
- } else {
- error_packet(remcom_out_buffer, -EINVAL);
- }
-}
-
-/* Handle the 'M' memory write bytes */
-static void gdb_cmd_memwrite(struct kgdb_state *ks)
-{
- int err = write_mem_msg(0);
-
- if (err)
- error_packet(remcom_out_buffer, err);
- else
- strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'X' memory binary write bytes */
-static void gdb_cmd_binwrite(struct kgdb_state *ks)
-{
- int err = write_mem_msg(1);
-
- if (err)
- error_packet(remcom_out_buffer, err);
- else
- strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'D' or 'k', detach or kill packets */
-static void gdb_cmd_detachkill(struct kgdb_state *ks)
-{
- int error;
-
- /* The detach case */
- if (remcom_in_buffer[0] == 'D') {
- error = remove_all_break();
- if (error < 0) {
- error_packet(remcom_out_buffer, error);
- } else {
- strcpy(remcom_out_buffer, "OK");
- kgdb_connected = 0;
- }
- put_packet(remcom_out_buffer);
- } else {
- /*
- * Assume the kill case, with no exit code checking,
- * trying to force detach the debugger:
- */
- remove_all_break();
- kgdb_connected = 0;
- }
-}
-
-/* Handle the 'R' reboot packets */
-static int gdb_cmd_reboot(struct kgdb_state *ks)
-{
- /* For now, only honor R0 */
- if (strcmp(remcom_in_buffer, "R0") == 0) {
- printk(KERN_CRIT "Executing emergency reboot\n");
- strcpy(remcom_out_buffer, "OK");
- put_packet(remcom_out_buffer);
-
- /*
- * Execution should not return from
- * machine_emergency_restart()
- */
- machine_emergency_restart();
- kgdb_connected = 0;
-
- return 1;
- }
- return 0;
-}
-
-/* Handle the 'q' query packets */
-static void gdb_cmd_query(struct kgdb_state *ks)
-{
- struct task_struct *g;
- struct task_struct *p;
- unsigned char thref[8];
- char *ptr;
- int i;
- int cpu;
- int finished = 0;
-
- switch (remcom_in_buffer[1]) {
- case 's':
- case 'f':
- if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
-
- i = 0;
- remcom_out_buffer[0] = 'm';
- ptr = remcom_out_buffer + 1;
- if (remcom_in_buffer[1] == 'f') {
- /* Each cpu is a shadow thread */
- for_each_online_cpu(cpu) {
- ks->thr_query = 0;
- int_to_threadref(thref, -cpu - 2);
- pack_threadid(ptr, thref);
- ptr += BUF_THREAD_ID_SIZE;
- *(ptr++) = ',';
- i++;
- }
- }
-
- do_each_thread(g, p) {
- if (i >= ks->thr_query && !finished) {
- int_to_threadref(thref, p->pid);
- pack_threadid(ptr, thref);
- ptr += BUF_THREAD_ID_SIZE;
- *(ptr++) = ',';
- ks->thr_query++;
- if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
- finished = 1;
- }
- i++;
- } while_each_thread(g, p);
-
- *(--ptr) = '\0';
- break;
-
- case 'C':
- /* Current thread id */
- strcpy(remcom_out_buffer, "QC");
- ks->threadid = shadow_pid(current->pid);
- int_to_threadref(thref, ks->threadid);
- pack_threadid(remcom_out_buffer + 2, thref);
- break;
- case 'T':
- if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- ks->threadid = 0;
- ptr = remcom_in_buffer + 17;
- kgdb_hex2long(&ptr, &ks->threadid);
- if (!getthread(ks->linux_regs, ks->threadid)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- if ((int)ks->threadid > 0) {
- kgdb_mem2hex(getthread(ks->linux_regs,
- ks->threadid)->comm,
- remcom_out_buffer, 16);
- } else {
- static char tmpstr[23 + BUF_THREAD_ID_SIZE];
-
- sprintf(tmpstr, "shadowCPU%d",
- (int)(-ks->threadid - 2));
- kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
- }
- break;
- }
-}
-
-/* Handle the 'H' task query packets */
-static void gdb_cmd_task(struct kgdb_state *ks)
-{
- struct task_struct *thread;
- char *ptr;
-
- switch (remcom_in_buffer[1]) {
- case 'g':
- ptr = &remcom_in_buffer[2];
- kgdb_hex2long(&ptr, &ks->threadid);
- thread = getthread(ks->linux_regs, ks->threadid);
- if (!thread && ks->threadid > 0) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_usethread = thread;
- ks->kgdb_usethreadid = ks->threadid;
- strcpy(remcom_out_buffer, "OK");
- break;
- case 'c':
- ptr = &remcom_in_buffer[2];
- kgdb_hex2long(&ptr, &ks->threadid);
- if (!ks->threadid) {
- kgdb_contthread = NULL;
- } else {
- thread = getthread(ks->linux_regs, ks->threadid);
- if (!thread && ks->threadid > 0) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_contthread = thread;
- }
- strcpy(remcom_out_buffer, "OK");
- break;
- }
-}
-
-/* Handle the 'T' thread query packets */
-static void gdb_cmd_thread(struct kgdb_state *ks)
-{
- char *ptr = &remcom_in_buffer[1];
- struct task_struct *thread;
-
- kgdb_hex2long(&ptr, &ks->threadid);
- thread = getthread(ks->linux_regs, ks->threadid);
- if (thread)
- strcpy(remcom_out_buffer, "OK");
- else
- error_packet(remcom_out_buffer, -EINVAL);
-}
-
-/* Handle the 'z' or 'Z' breakpoint remove or set packets */
-static void gdb_cmd_break(struct kgdb_state *ks)
-{
- /*
- * Since GDB-5.3, it's been drafted that '0' is a software
- * breakpoint, '1' is a hardware breakpoint, so let's do that.
- */
- char *bpt_type = &remcom_in_buffer[1];
- char *ptr = &remcom_in_buffer[2];
- unsigned long addr;
- unsigned long length;
- int error = 0;
-
- if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
- /* Unsupported */
- if (*bpt_type > '4')
- return;
- } else {
- if (*bpt_type != '0' && *bpt_type != '1')
- /* Unsupported. */
- return;
- }
-
- /*
- * Test if this is a hardware breakpoint, and
- * if we support it:
- */
- if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
- /* Unsupported. */
- return;
-
- if (*(ptr++) != ',') {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
- if (!kgdb_hex2long(&ptr, &addr)) {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
- if (*(ptr++) != ',' ||
- !kgdb_hex2long(&ptr, &length)) {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
-
- if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
- error = kgdb_set_sw_break(addr);
- else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
- error = kgdb_remove_sw_break(addr);
- else if (remcom_in_buffer[0] == 'Z')
- error = arch_kgdb_ops.set_hw_breakpoint(addr,
- (int)length, *bpt_type - '0');
- else if (remcom_in_buffer[0] == 'z')
- error = arch_kgdb_ops.remove_hw_breakpoint(addr,
- (int) length, *bpt_type - '0');
-
- if (error == 0)
- strcpy(remcom_out_buffer, "OK");
- else
- error_packet(remcom_out_buffer, error);
-}
-
-/* Handle the 'C' signal / exception passing packets */
-static int gdb_cmd_exception_pass(struct kgdb_state *ks)
-{
- /* C09 == pass exception
- * C15 == detach kgdb, pass exception
- */
- if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
-
- ks->pass_exception = 1;
- remcom_in_buffer[0] = 'c';
-
- } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
-
- ks->pass_exception = 1;
- remcom_in_buffer[0] = 'D';
- remove_all_break();
- kgdb_connected = 0;
- return 1;
-
- } else {
- kgdb_msg_write("KGDB only knows signal 9 (pass)"
- " and 15 (pass and disconnect)\n"
- "Executing a continue without signal passing\n", 0);
- remcom_in_buffer[0] = 'c';
- }
-
- /* Indicate fall through */
- return -1;
-}
-
-/*
- * This function performs all gdbserial command procesing
- */
-static int gdb_serial_stub(struct kgdb_state *ks)
-{
- int error = 0;
- int tmp;
-
- /* Clear the out buffer. */
- memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
- if (kgdb_connected) {
- unsigned char thref[8];
- char *ptr;
-
- /* Reply to host that an exception has occurred */
- ptr = remcom_out_buffer;
- *ptr++ = 'T';
- ptr = pack_hex_byte(ptr, ks->signo);
- ptr += strlen(strcpy(ptr, "thread:"));
- int_to_threadref(thref, shadow_pid(current->pid));
- ptr = pack_threadid(ptr, thref);
- *ptr++ = ';';
- put_packet(remcom_out_buffer);
- }
-
- kgdb_usethread = kgdb_info[ks->cpu].task;
- ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
- ks->pass_exception = 0;
-
- while (1) {
- error = 0;
-
- /* Clear the out buffer. */
- memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
- get_packet(remcom_in_buffer);
-
- switch (remcom_in_buffer[0]) {
- case '?': /* gdbserial status */
- gdb_cmd_status(ks);
- break;
- case 'g': /* return the value of the CPU registers */
- gdb_cmd_getregs(ks);
- break;
- case 'G': /* set the value of the CPU registers - return OK */
- gdb_cmd_setregs(ks);
- break;
- case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
- gdb_cmd_memread(ks);
- break;
- case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
- gdb_cmd_memwrite(ks);
- break;
- case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
- gdb_cmd_binwrite(ks);
- break;
- /* kill or detach. KGDB should treat this like a
- * continue.
- */
- case 'D': /* Debugger detach */
- case 'k': /* Debugger detach via kill */
- gdb_cmd_detachkill(ks);
- goto default_handle;
- case 'R': /* Reboot */
- if (gdb_cmd_reboot(ks))
- goto default_handle;
- break;
- case 'q': /* query command */
- gdb_cmd_query(ks);
- break;
- case 'H': /* task related */
- gdb_cmd_task(ks);
- break;
- case 'T': /* Query thread status */
- gdb_cmd_thread(ks);
- break;
- case 'z': /* Break point remove */
- case 'Z': /* Break point set */
- gdb_cmd_break(ks);
- break;
- case 'C': /* Exception passing */
- tmp = gdb_cmd_exception_pass(ks);
- if (tmp > 0)
- goto default_handle;
- if (tmp == 0)
- break;
- /* Fall through on tmp < 0 */
- case 'c': /* Continue packet */
- case 's': /* Single step packet */
- if (kgdb_contthread && kgdb_contthread != current) {
- /* Can't switch threads in kgdb */
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_activate_sw_breakpoints();
- /* Fall through to default processing */
- default:
-default_handle:
- error = kgdb_arch_handle_exception(ks->ex_vector,
- ks->signo,
- ks->err_code,
- remcom_in_buffer,
- remcom_out_buffer,
- ks->linux_regs);
- /*
- * Leave cmd processing on error, detach,
- * kill, continue, or single step.
- */
- if (error >= 0 || remcom_in_buffer[0] == 'D' ||
- remcom_in_buffer[0] == 'k') {
- error = 0;
- goto kgdb_exit;
- }
-
- }
-
- /* reply to the request */
- put_packet(remcom_out_buffer);
- }
-
-kgdb_exit:
- if (ks->pass_exception)
- error = 1;
- return error;
-}
-
-static int kgdb_reenter_check(struct kgdb_state *ks)
-{
- unsigned long addr;
-
- if (atomic_read(&kgdb_active) != raw_smp_processor_id())
- return 0;
-
- /* Panic on recursive debugger calls: */
- exception_level++;
- addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
- kgdb_deactivate_sw_breakpoints();
-
- /*
- * If the break point removed ok at the place exception
- * occurred, try to recover and print a warning to the end
- * user because the user planted a breakpoint in a place that
- * KGDB needs in order to function.
- */
- if (kgdb_remove_sw_break(addr) == 0) {
- exception_level = 0;
- kgdb_skipexception(ks->ex_vector, ks->linux_regs);
- kgdb_activate_sw_breakpoints();
- printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n",
- addr);
- WARN_ON_ONCE(1);
-
- return 1;
- }
- remove_all_break();
- kgdb_skipexception(ks->ex_vector, ks->linux_regs);
-
- if (exception_level > 1) {
- dump_stack();
- panic("Recursive entry to debugger");
- }
-
- printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
- dump_stack();
- panic("Recursive entry to debugger");
-
- return 1;
-}
-
-/*
- * kgdb_handle_exception() - main entry point from a kernel exception
- *
- * Locking hierarchy:
- * interface locks, if any (begin_session)
- * kgdb lock (kgdb_active)
- */
-int
-kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
-{
- struct kgdb_state kgdb_var;
- struct kgdb_state *ks = &kgdb_var;
- unsigned long flags;
- int sstep_tries = 100;
- int error = 0;
- int i, cpu;
-
- ks->cpu = raw_smp_processor_id();
- ks->ex_vector = evector;
- ks->signo = signo;
- ks->ex_vector = evector;
- ks->err_code = ecode;
- ks->kgdb_usethreadid = 0;
- ks->linux_regs = regs;
-
- if (kgdb_reenter_check(ks))
- return 0; /* Ouch, double exception ! */
-
-acquirelock:
- /*
- * Interrupts will be restored by the 'trap return' code, except when
- * single stepping.
- */
- local_irq_save(flags);
-
- cpu = raw_smp_processor_id();
-
- /*
- * Acquire the kgdb_active lock:
- */
- while (atomic_cmpxchg(&kgdb_active, -1, cpu) != -1)
- cpu_relax();
-
- /*
- * For single stepping, try to only enter on the processor
- * that was single stepping. To gaurd against a deadlock, the
- * kernel will only try for the value of sstep_tries before
- * giving up and continuing on.
- */
- if (atomic_read(&kgdb_cpu_doing_single_step) != -1 &&
- (kgdb_info[cpu].task &&
- kgdb_info[cpu].task->pid != kgdb_sstep_pid) && --sstep_tries) {
- atomic_set(&kgdb_active, -1);
- touch_softlockup_watchdog_sync();
- clocksource_touch_watchdog();
- local_irq_restore(flags);
-
- goto acquirelock;
- }
-
- if (!kgdb_io_ready(1)) {
- error = 1;
- goto kgdb_restore; /* No I/O connection, so resume the system */
- }
-
- /*
- * Don't enter if we have hit a removed breakpoint.
- */
- if (kgdb_skipexception(ks->ex_vector, ks->linux_regs))
- goto kgdb_restore;
-
- /* Call the I/O driver's pre_exception routine */
- if (kgdb_io_ops->pre_exception)
- kgdb_io_ops->pre_exception();
-
- kgdb_info[ks->cpu].debuggerinfo = ks->linux_regs;
- kgdb_info[ks->cpu].task = current;
-
- kgdb_disable_hw_debug(ks->linux_regs);
-
- /*
- * Get the passive CPU lock which will hold all the non-primary
- * CPU in a spin state while the debugger is active
- */
- if (!kgdb_single_step) {
- for (i = 0; i < NR_CPUS; i++)
- atomic_set(&passive_cpu_wait[i], 1);
- }
-
- /*
- * spin_lock code is good enough as a barrier so we don't
- * need one here:
- */
- atomic_set(&cpu_in_kgdb[ks->cpu], 1);
-
-#ifdef CONFIG_SMP
- /* Signal the other CPUs to enter kgdb_wait() */
- if ((!kgdb_single_step) && kgdb_do_roundup)
- kgdb_roundup_cpus(flags);
-#endif
-
- /*
- * Wait for the other CPUs to be notified and be waiting for us:
- */
- for_each_online_cpu(i) {
- while (!atomic_read(&cpu_in_kgdb[i]))
- cpu_relax();
- }
-
- /*
- * At this point the primary processor is completely
- * in the debugger and all secondary CPUs are quiescent
- */
- kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
- kgdb_deactivate_sw_breakpoints();
- kgdb_single_step = 0;
- kgdb_contthread = current;
- exception_level = 0;
-
- /* Talk to debugger with gdbserial protocol */
- error = gdb_serial_stub(ks);
-
- /* Call the I/O driver's post_exception routine */
- if (kgdb_io_ops->post_exception)
- kgdb_io_ops->post_exception();
-
- kgdb_info[ks->cpu].debuggerinfo = NULL;
- kgdb_info[ks->cpu].task = NULL;
- atomic_set(&cpu_in_kgdb[ks->cpu], 0);
-
- if (!kgdb_single_step) {
- for (i = NR_CPUS-1; i >= 0; i--)
- atomic_set(&passive_cpu_wait[i], 0);
- /*
- * Wait till all the CPUs have quit
- * from the debugger.
- */
- for_each_online_cpu(i) {
- while (atomic_read(&cpu_in_kgdb[i]))
- cpu_relax();
- }
- }
-
-kgdb_restore:
- if (atomic_read(&kgdb_cpu_doing_single_step) != -1) {
- int sstep_cpu = atomic_read(&kgdb_cpu_doing_single_step);
- if (kgdb_info[sstep_cpu].task)
- kgdb_sstep_pid = kgdb_info[sstep_cpu].task->pid;
- else
- kgdb_sstep_pid = 0;
- }
- /* Free kgdb_active */
- atomic_set(&kgdb_active, -1);
- touch_softlockup_watchdog_sync();
- clocksource_touch_watchdog();
- local_irq_restore(flags);
-
- return error;
-}
-
-int kgdb_nmicallback(int cpu, void *regs)
-{
-#ifdef CONFIG_SMP
- if (!atomic_read(&cpu_in_kgdb[cpu]) &&
- atomic_read(&kgdb_active) != cpu &&
- atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)])) {
- kgdb_wait((struct pt_regs *)regs);
- return 0;
- }
-#endif
- return 1;
-}
-
-static void kgdb_console_write(struct console *co, const char *s,
- unsigned count)
-{
- unsigned long flags;
-
- /* If we're debugging, or KGDB has not connected, don't try
- * and print. */
- if (!kgdb_connected || atomic_read(&kgdb_active) != -1)
- return;
-
- local_irq_save(flags);
- kgdb_msg_write(s, count);
- local_irq_restore(flags);
-}
-
-static struct console kgdbcons = {
- .name = "kgdb",
- .write = kgdb_console_write,
- .flags = CON_PRINTBUFFER | CON_ENABLED,
- .index = -1,
-};
-
-#ifdef CONFIG_MAGIC_SYSRQ
-static void sysrq_handle_gdb(int key, struct tty_struct *tty)
-{
- if (!kgdb_io_ops) {
- printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
- return;
- }
- if (!kgdb_connected)
- printk(KERN_CRIT "Entering KGDB\n");
-
- kgdb_breakpoint();
-}
-
-static struct sysrq_key_op sysrq_gdb_op = {
- .handler = sysrq_handle_gdb,
- .help_msg = "debug(G)",
- .action_msg = "DEBUG",
-};
-#endif
-
-static void kgdb_register_callbacks(void)
-{
- if (!kgdb_io_module_registered) {
- kgdb_io_module_registered = 1;
- kgdb_arch_init();
-#ifdef CONFIG_MAGIC_SYSRQ
- register_sysrq_key('g', &sysrq_gdb_op);
-#endif
- if (kgdb_use_con && !kgdb_con_registered) {
- register_console(&kgdbcons);
- kgdb_con_registered = 1;
- }
- }
-}
-
-static void kgdb_unregister_callbacks(void)
-{
- /*
- * When this routine is called KGDB should unregister from the
- * panic handler and clean up, making sure it is not handling any
- * break exceptions at the time.
- */
- if (kgdb_io_module_registered) {
- kgdb_io_module_registered = 0;
- kgdb_arch_exit();
-#ifdef CONFIG_MAGIC_SYSRQ
- unregister_sysrq_key('g', &sysrq_gdb_op);
-#endif
- if (kgdb_con_registered) {
- unregister_console(&kgdbcons);
- kgdb_con_registered = 0;
- }
- }
-}
-
-static void kgdb_initial_breakpoint(void)
-{
- kgdb_break_asap = 0;
-
- printk(KERN_CRIT "kgdb: Waiting for connection from remote gdb...\n");
- kgdb_breakpoint();
-}
-
-/**
- * kgdb_register_io_module - register KGDB IO module
- * @new_kgdb_io_ops: the io ops vector
- *
- * Register it with the KGDB core.
- */
-int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops)
-{
- int err;
-
- spin_lock(&kgdb_registration_lock);
-
- if (kgdb_io_ops) {
- spin_unlock(&kgdb_registration_lock);
-
- printk(KERN_ERR "kgdb: Another I/O driver is already "
- "registered with KGDB.\n");
- return -EBUSY;
- }
-
- if (new_kgdb_io_ops->init) {
- err = new_kgdb_io_ops->init();
- if (err) {
- spin_unlock(&kgdb_registration_lock);
- return err;
- }
- }
-
- kgdb_io_ops = new_kgdb_io_ops;
-
- spin_unlock(&kgdb_registration_lock);
-
- printk(KERN_INFO "kgdb: Registered I/O driver %s.\n",
- new_kgdb_io_ops->name);
-
- /* Arm KGDB now. */
- kgdb_register_callbacks();
-
- if (kgdb_break_asap)
- kgdb_initial_breakpoint();
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(kgdb_register_io_module);
-
-/**
- * kkgdb_unregister_io_module - unregister KGDB IO module
- * @old_kgdb_io_ops: the io ops vector
- *
- * Unregister it with the KGDB core.
- */
-void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops)
-{
- BUG_ON(kgdb_connected);
-
- /*
- * KGDB is no longer able to communicate out, so
- * unregister our callbacks and reset state.
- */
- kgdb_unregister_callbacks();
-
- spin_lock(&kgdb_registration_lock);
-
- WARN_ON_ONCE(kgdb_io_ops != old_kgdb_io_ops);
- kgdb_io_ops = NULL;
-
- spin_unlock(&kgdb_registration_lock);
-
- printk(KERN_INFO
- "kgdb: Unregistered I/O driver %s, debugger disabled.\n",
- old_kgdb_io_ops->name);
-}
-EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
-
-/**
- * kgdb_breakpoint - generate breakpoint exception
- *
- * This function will generate a breakpoint exception. It is used at the
- * beginning of a program to sync up with a debugger and can be used
- * otherwise as a quick means to stop program execution and "break" into
- * the debugger.
- */
-void kgdb_breakpoint(void)
-{
- atomic_set(&kgdb_setting_breakpoint, 1);
- wmb(); /* Sync point before breakpoint */
- arch_kgdb_breakpoint();
- wmb(); /* Sync point after breakpoint */
- atomic_set(&kgdb_setting_breakpoint, 0);
-}
-EXPORT_SYMBOL_GPL(kgdb_breakpoint);
-
-static int __init opt_kgdb_wait(char *str)
-{
- kgdb_break_asap = 1;
-
- if (kgdb_io_module_registered)
- kgdb_initial_breakpoint();
-
- return 0;
-}
-
-early_param("kgdbwait", opt_kgdb_wait);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 04/40] Separate the gdbstub from the debug core
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (2 preceding siblings ...)
2010-01-14 14:58 ` [PATCH 03/40] Move kernel/kgdb.c to kernel/debug/debug_core.c Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 05/40] kgdb: eliminate kgdb_wait(), all cpus enter the same way Jason Wessel
` (36 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Split the former kernel/kgdb.c into debug_core.c which contains the
kernel debugger exception logic and to the gdbstub.c which contains
the logic for allowing gdb to talk to the debug core.
This also created a private include file called debug_core.h which
contains all the definitions to glue the debug_core to any other
debugger connections.
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/debug/Makefile | 2 +-
kernel/debug/debug_core.c | 992 ++-------------------------------------------
kernel/debug/debug_core.h | 49 +++
kernel/debug/gdbstub.c | 939 ++++++++++++++++++++++++++++++++++++++++++
4 files changed, 1028 insertions(+), 954 deletions(-)
create mode 100644 kernel/debug/debug_core.h
create mode 100644 kernel/debug/gdbstub.c
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile
index 5287fc8..3657c64 100644
--- a/kernel/debug/Makefile
+++ b/kernel/debug/Makefile
@@ -2,4 +2,4 @@
# Makefile for the linux kernel debugger
#
-obj-$(CONFIG_KGDB) += debug_core.o
\ No newline at end of file
+obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o
\ No newline at end of file
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 761fdd2..ad3caaa 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -1,5 +1,5 @@
/*
- * KGDB stub.
+ * Kernel Debug Core
*
* Maintainer: Jason Wessel <jason.wessel@windriver.com>
*
@@ -9,7 +9,7 @@
* Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
* Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
* Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
- * Copyright (C) 2005-2008 Wind River Systems, Inc.
+ * Copyright (C) 2005-2009 Wind River Systems, Inc.
* Copyright (C) 2007 MontaVista Software, Inc.
* Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*
@@ -37,7 +37,6 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ptrace.h>
-#include <linux/reboot.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/sched.h>
@@ -52,27 +51,12 @@
#include <asm/byteorder.h>
#include <asm/atomic.h>
#include <asm/system.h>
-#include <asm/unaligned.h>
-static int kgdb_break_asap;
+#include "debug_core.h"
-#define KGDB_MAX_THREAD_QUERY 17
-struct kgdb_state {
- int ex_vector;
- int signo;
- int err_code;
- int cpu;
- int pass_exception;
- unsigned long thr_query;
- unsigned long threadid;
- long kgdb_usethreadid;
- struct pt_regs *linux_regs;
-};
+static int kgdb_break_asap;
-static struct debuggerinfo_struct {
- void *debuggerinfo;
- struct task_struct *task;
-} kgdb_info[NR_CPUS];
+struct debuggerinfo_struct kgdb_info[NR_CPUS];
/**
* kgdb_connected - Is a host GDB connected to us?
@@ -86,7 +70,7 @@ static int kgdb_io_module_registered;
/* Guard for recursive entry */
static int exception_level;
-static struct kgdb_io *kgdb_io_ops;
+struct kgdb_io *dbg_io_ops;
static DEFINE_SPINLOCK(kgdb_registration_lock);
/* kgdb console driver is loaded */
@@ -129,16 +113,7 @@ struct task_struct *kgdb_usethread;
struct task_struct *kgdb_contthread;
int kgdb_single_step;
-pid_t kgdb_sstep_pid;
-
-/* Our I/O buffers. */
-static char remcom_in_buffer[BUFMAX];
-static char remcom_out_buffer[BUFMAX];
-
-/* Storage for the registers, in GDB format. */
-static unsigned long gdb_regs[(NUMREGBYTES +
- sizeof(unsigned long) - 1) /
- sizeof(unsigned long)];
+static pid_t kgdb_sstep_pid;
/* to keep track of the CPU which is doing the single stepping*/
atomic_t kgdb_cpu_doing_single_step = ATOMIC_INIT(-1);
@@ -240,329 +215,6 @@ void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
}
/*
- * GDB remote protocol parser:
- */
-
-static int hex(char ch)
-{
- if ((ch >= 'a') && (ch <= 'f'))
- return ch - 'a' + 10;
- if ((ch >= '0') && (ch <= '9'))
- return ch - '0';
- if ((ch >= 'A') && (ch <= 'F'))
- return ch - 'A' + 10;
- return -1;
-}
-
-/* scan for the sequence $<data>#<checksum> */
-static void get_packet(char *buffer)
-{
- unsigned char checksum;
- unsigned char xmitcsum;
- int count;
- char ch;
-
- do {
- /*
- * Spin and wait around for the start character, ignore all
- * other characters:
- */
- while ((ch = (kgdb_io_ops->read_char())) != '$')
- /* nothing */;
-
- kgdb_connected = 1;
- checksum = 0;
- xmitcsum = -1;
-
- count = 0;
-
- /*
- * now, read until a # or end of buffer is found:
- */
- while (count < (BUFMAX - 1)) {
- ch = kgdb_io_ops->read_char();
- if (ch == '#')
- break;
- checksum = checksum + ch;
- buffer[count] = ch;
- count = count + 1;
- }
- buffer[count] = 0;
-
- if (ch == '#') {
- xmitcsum = hex(kgdb_io_ops->read_char()) << 4;
- xmitcsum += hex(kgdb_io_ops->read_char());
-
- if (checksum != xmitcsum)
- /* failed checksum */
- kgdb_io_ops->write_char('-');
- else
- /* successful transfer */
- kgdb_io_ops->write_char('+');
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
- }
- } while (checksum != xmitcsum);
-}
-
-/*
- * Send the packet in buffer.
- * Check for gdb connection if asked for.
- */
-static void put_packet(char *buffer)
-{
- unsigned char checksum;
- int count;
- char ch;
-
- /*
- * $<packet info>#<checksum>.
- */
- while (1) {
- kgdb_io_ops->write_char('$');
- checksum = 0;
- count = 0;
-
- while ((ch = buffer[count])) {
- kgdb_io_ops->write_char(ch);
- checksum += ch;
- count++;
- }
-
- kgdb_io_ops->write_char('#');
- kgdb_io_ops->write_char(hex_asc_hi(checksum));
- kgdb_io_ops->write_char(hex_asc_lo(checksum));
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
-
- /* Now see what we get in reply. */
- ch = kgdb_io_ops->read_char();
-
- if (ch == 3)
- ch = kgdb_io_ops->read_char();
-
- /* If we get an ACK, we are done. */
- if (ch == '+')
- return;
-
- /*
- * If we get the start of another packet, this means
- * that GDB is attempting to reconnect. We will NAK
- * the packet being sent, and stop trying to send this
- * packet.
- */
- if (ch == '$') {
- kgdb_io_ops->write_char('-');
- if (kgdb_io_ops->flush)
- kgdb_io_ops->flush();
- return;
- }
- }
-}
-
-/*
- * Convert the memory pointed to by mem into hex, placing result in buf.
- * Return a pointer to the last char put in buf (null). May return an error.
- */
-int kgdb_mem2hex(char *mem, char *buf, int count)
-{
- char *tmp;
- int err;
-
- /*
- * We use the upper half of buf as an intermediate buffer for the
- * raw memory copy. Hex conversion will work against this one.
- */
- tmp = buf + count;
-
- err = probe_kernel_read(tmp, mem, count);
- if (!err) {
- while (count > 0) {
- buf = pack_hex_byte(buf, *tmp);
- tmp++;
- count--;
- }
-
- *buf = 0;
- }
-
- return err;
-}
-
-/*
- * Copy the binary array pointed to by buf into mem. Fix $, #, and
- * 0x7d escaped with 0x7d. Return a pointer to the character after
- * the last byte written.
- */
-static int kgdb_ebin2mem(char *buf, char *mem, int count)
-{
- int err = 0;
- char c;
-
- while (count-- > 0) {
- c = *buf++;
- if (c == 0x7d)
- c = *buf++ ^ 0x20;
-
- err = probe_kernel_write(mem, &c, 1);
- if (err)
- break;
-
- mem++;
- }
-
- return err;
-}
-
-/*
- * Convert the hex array pointed to by buf into binary to be placed in mem.
- * Return a pointer to the character AFTER the last byte written.
- * May return an error.
- */
-int kgdb_hex2mem(char *buf, char *mem, int count)
-{
- char *tmp_raw;
- char *tmp_hex;
-
- /*
- * We use the upper half of buf as an intermediate buffer for the
- * raw memory that is converted from hex.
- */
- tmp_raw = buf + count * 2;
-
- tmp_hex = tmp_raw - 1;
- while (tmp_hex >= buf) {
- tmp_raw--;
- *tmp_raw = hex(*tmp_hex--);
- *tmp_raw |= hex(*tmp_hex--) << 4;
- }
-
- return probe_kernel_write(mem, tmp_raw, count);
-}
-
-/*
- * While we find nice hex chars, build a long_val.
- * Return number of chars processed.
- */
-int kgdb_hex2long(char **ptr, unsigned long *long_val)
-{
- int hex_val;
- int num = 0;
- int negate = 0;
-
- *long_val = 0;
-
- if (**ptr == '-') {
- negate = 1;
- (*ptr)++;
- }
- while (**ptr) {
- hex_val = hex(**ptr);
- if (hex_val < 0)
- break;
-
- *long_val = (*long_val << 4) | hex_val;
- num++;
- (*ptr)++;
- }
-
- if (negate)
- *long_val = -*long_val;
-
- return num;
-}
-
-/* Write memory due to an 'M' or 'X' packet. */
-static int write_mem_msg(int binary)
-{
- char *ptr = &remcom_in_buffer[1];
- unsigned long addr;
- unsigned long length;
- int err;
-
- if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
- kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
- if (binary)
- err = kgdb_ebin2mem(ptr, (char *)addr, length);
- else
- err = kgdb_hex2mem(ptr, (char *)addr, length);
- if (err)
- return err;
- if (CACHE_FLUSH_IS_SAFE)
- flush_icache_range(addr, addr + length);
- return 0;
- }
-
- return -EINVAL;
-}
-
-static void error_packet(char *pkt, int error)
-{
- error = -error;
- pkt[0] = 'E';
- pkt[1] = hex_asc[(error / 10)];
- pkt[2] = hex_asc[(error % 10)];
- pkt[3] = '\0';
-}
-
-/*
- * Thread ID accessors. We represent a flat TID space to GDB, where
- * the per CPU idle threads (which under Linux all have PID 0) are
- * remapped to negative TIDs.
- */
-
-#define BUF_THREAD_ID_SIZE 16
-
-static char *pack_threadid(char *pkt, unsigned char *id)
-{
- char *limit;
-
- limit = pkt + BUF_THREAD_ID_SIZE;
- while (pkt < limit)
- pkt = pack_hex_byte(pkt, *id++);
-
- return pkt;
-}
-
-static void int_to_threadref(unsigned char *id, int value)
-{
- unsigned char *scan;
- int i = 4;
-
- scan = (unsigned char *)id;
- while (i--)
- *scan++ = 0;
- put_unaligned_be32(value, scan);
-}
-
-static struct task_struct *getthread(struct pt_regs *regs, int tid)
-{
- /*
- * Non-positive TIDs are remapped to the cpu shadow information
- */
- if (tid == 0 || tid == -1)
- tid = -atomic_read(&kgdb_active) - 2;
- if (tid < -1 && tid > -NR_CPUS - 2) {
- if (kgdb_info[-tid - 2].task)
- return kgdb_info[-tid - 2].task;
- else
- return idle_task(-tid - 2);
- }
- if (tid <= 0) {
- printk(KERN_ERR "KGDB: Internal thread select error\n");
- dump_stack();
- return NULL;
- }
-
- /*
- * find_task_by_pid_ns() does not take the tasklist lock anymore
- * but is nicely RCU locked - hence is a pretty resilient
- * thing to use:
- */
- return find_task_by_pid_ns(tid, &init_pid_ns);
-}
-
-/*
* CPU debug state control:
*/
@@ -625,7 +277,7 @@ static void kgdb_flush_swbreak_addr(unsigned long addr)
/*
* SW breakpoint management:
*/
-static int kgdb_activate_sw_breakpoints(void)
+int dbg_activate_sw_breakpoints(void)
{
unsigned long addr;
int error;
@@ -651,7 +303,7 @@ static int kgdb_activate_sw_breakpoints(void)
return ret;
}
-static int kgdb_set_sw_break(unsigned long addr)
+int dbg_set_sw_break(unsigned long addr)
{
int err = kgdb_validate_break_address(addr);
int breakno = -1;
@@ -716,7 +368,7 @@ static int kgdb_deactivate_sw_breakpoints(void)
return ret;
}
-static int kgdb_remove_sw_break(unsigned long addr)
+int dbg_remove_sw_break(unsigned long addr)
{
int i;
@@ -742,7 +394,7 @@ int kgdb_isremovedbreak(unsigned long addr)
return 0;
}
-static int remove_all_break(void)
+int dbg_remove_all_break(void)
{
unsigned long addr;
int error;
@@ -770,53 +422,6 @@ setundefined:
}
/*
- * Remap normal tasks to their real PID,
- * CPU shadow threads are mapped to -CPU - 2
- */
-static inline int shadow_pid(int realpid)
-{
- if (realpid)
- return realpid;
-
- return -raw_smp_processor_id() - 2;
-}
-
-static char gdbmsgbuf[BUFMAX + 1];
-
-static void kgdb_msg_write(const char *s, int len)
-{
- char *bufptr;
- int wcount;
- int i;
-
- /* 'O'utput */
- gdbmsgbuf[0] = 'O';
-
- /* Fill and send buffers... */
- while (len > 0) {
- bufptr = gdbmsgbuf + 1;
-
- /* Calculate how many this time */
- if ((len << 1) > (BUFMAX - 2))
- wcount = (BUFMAX - 2) >> 1;
- else
- wcount = len;
-
- /* Pack in hex chars */
- for (i = 0; i < wcount; i++)
- bufptr = pack_hex_byte(bufptr, s[i]);
- *bufptr = '\0';
-
- /* Move up */
- s += wcount;
- len -= wcount;
-
- /* Write packet */
- put_packet(gdbmsgbuf);
- }
-}
-
-/*
* Return true if there is a valid kgdb I/O module. Also if no
* debugger is attached a message can be printed to the console about
* waiting for the debugger to attach.
@@ -827,7 +432,7 @@ static void kgdb_msg_write(const char *s, int len)
*/
static int kgdb_io_ready(int print_wait)
{
- if (!kgdb_io_ops)
+ if (!dbg_io_ops)
return 0;
if (kgdb_connected)
return 1;
@@ -838,525 +443,6 @@ static int kgdb_io_ready(int print_wait)
return 1;
}
-/*
- * All the functions that start with gdb_cmd are the various
- * operations to implement the handlers for the gdbserial protocol
- * where KGDB is communicating with an external debugger
- */
-
-/* Handle the '?' status packets */
-static void gdb_cmd_status(struct kgdb_state *ks)
-{
- /*
- * We know that this packet is only sent
- * during initial connect. So to be safe,
- * we clear out our breakpoints now in case
- * GDB is reconnecting.
- */
- remove_all_break();
-
- remcom_out_buffer[0] = 'S';
- pack_hex_byte(&remcom_out_buffer[1], ks->signo);
-}
-
-/* Handle the 'g' get registers request */
-static void gdb_cmd_getregs(struct kgdb_state *ks)
-{
- struct task_struct *thread;
- void *local_debuggerinfo;
- int i;
-
- thread = kgdb_usethread;
- if (!thread) {
- thread = kgdb_info[ks->cpu].task;
- local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
- } else {
- local_debuggerinfo = NULL;
- for_each_online_cpu(i) {
- /*
- * Try to find the task on some other
- * or possibly this node if we do not
- * find the matching task then we try
- * to approximate the results.
- */
- if (thread == kgdb_info[i].task)
- local_debuggerinfo = kgdb_info[i].debuggerinfo;
- }
- }
-
- /*
- * All threads that don't have debuggerinfo should be
- * in schedule() sleeping, since all other CPUs
- * are in kgdb_wait, and thus have debuggerinfo.
- */
- if (local_debuggerinfo) {
- pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
- } else {
- /*
- * Pull stuff saved during switch_to; nothing
- * else is accessible (or even particularly
- * relevant).
- *
- * This should be enough for a stack trace.
- */
- sleeping_thread_to_gdb_regs(gdb_regs, thread);
- }
- kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
-}
-
-/* Handle the 'G' set registers request */
-static void gdb_cmd_setregs(struct kgdb_state *ks)
-{
- kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
-
- if (kgdb_usethread && kgdb_usethread != current) {
- error_packet(remcom_out_buffer, -EINVAL);
- } else {
- gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
- strcpy(remcom_out_buffer, "OK");
- }
-}
-
-/* Handle the 'm' memory read bytes */
-static void gdb_cmd_memread(struct kgdb_state *ks)
-{
- char *ptr = &remcom_in_buffer[1];
- unsigned long length;
- unsigned long addr;
- int err;
-
- if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
- kgdb_hex2long(&ptr, &length) > 0) {
- err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
- if (err)
- error_packet(remcom_out_buffer, err);
- } else {
- error_packet(remcom_out_buffer, -EINVAL);
- }
-}
-
-/* Handle the 'M' memory write bytes */
-static void gdb_cmd_memwrite(struct kgdb_state *ks)
-{
- int err = write_mem_msg(0);
-
- if (err)
- error_packet(remcom_out_buffer, err);
- else
- strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'X' memory binary write bytes */
-static void gdb_cmd_binwrite(struct kgdb_state *ks)
-{
- int err = write_mem_msg(1);
-
- if (err)
- error_packet(remcom_out_buffer, err);
- else
- strcpy(remcom_out_buffer, "OK");
-}
-
-/* Handle the 'D' or 'k', detach or kill packets */
-static void gdb_cmd_detachkill(struct kgdb_state *ks)
-{
- int error;
-
- /* The detach case */
- if (remcom_in_buffer[0] == 'D') {
- error = remove_all_break();
- if (error < 0) {
- error_packet(remcom_out_buffer, error);
- } else {
- strcpy(remcom_out_buffer, "OK");
- kgdb_connected = 0;
- }
- put_packet(remcom_out_buffer);
- } else {
- /*
- * Assume the kill case, with no exit code checking,
- * trying to force detach the debugger:
- */
- remove_all_break();
- kgdb_connected = 0;
- }
-}
-
-/* Handle the 'R' reboot packets */
-static int gdb_cmd_reboot(struct kgdb_state *ks)
-{
- /* For now, only honor R0 */
- if (strcmp(remcom_in_buffer, "R0") == 0) {
- printk(KERN_CRIT "Executing emergency reboot\n");
- strcpy(remcom_out_buffer, "OK");
- put_packet(remcom_out_buffer);
-
- /*
- * Execution should not return from
- * machine_emergency_restart()
- */
- machine_emergency_restart();
- kgdb_connected = 0;
-
- return 1;
- }
- return 0;
-}
-
-/* Handle the 'q' query packets */
-static void gdb_cmd_query(struct kgdb_state *ks)
-{
- struct task_struct *g;
- struct task_struct *p;
- unsigned char thref[8];
- char *ptr;
- int i;
- int cpu;
- int finished = 0;
-
- switch (remcom_in_buffer[1]) {
- case 's':
- case 'f':
- if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
-
- i = 0;
- remcom_out_buffer[0] = 'm';
- ptr = remcom_out_buffer + 1;
- if (remcom_in_buffer[1] == 'f') {
- /* Each cpu is a shadow thread */
- for_each_online_cpu(cpu) {
- ks->thr_query = 0;
- int_to_threadref(thref, -cpu - 2);
- pack_threadid(ptr, thref);
- ptr += BUF_THREAD_ID_SIZE;
- *(ptr++) = ',';
- i++;
- }
- }
-
- do_each_thread(g, p) {
- if (i >= ks->thr_query && !finished) {
- int_to_threadref(thref, p->pid);
- pack_threadid(ptr, thref);
- ptr += BUF_THREAD_ID_SIZE;
- *(ptr++) = ',';
- ks->thr_query++;
- if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
- finished = 1;
- }
- i++;
- } while_each_thread(g, p);
-
- *(--ptr) = '\0';
- break;
-
- case 'C':
- /* Current thread id */
- strcpy(remcom_out_buffer, "QC");
- ks->threadid = shadow_pid(current->pid);
- int_to_threadref(thref, ks->threadid);
- pack_threadid(remcom_out_buffer + 2, thref);
- break;
- case 'T':
- if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- ks->threadid = 0;
- ptr = remcom_in_buffer + 17;
- kgdb_hex2long(&ptr, &ks->threadid);
- if (!getthread(ks->linux_regs, ks->threadid)) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- if ((int)ks->threadid > 0) {
- kgdb_mem2hex(getthread(ks->linux_regs,
- ks->threadid)->comm,
- remcom_out_buffer, 16);
- } else {
- static char tmpstr[23 + BUF_THREAD_ID_SIZE];
-
- sprintf(tmpstr, "shadowCPU%d",
- (int)(-ks->threadid - 2));
- kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
- }
- break;
- }
-}
-
-/* Handle the 'H' task query packets */
-static void gdb_cmd_task(struct kgdb_state *ks)
-{
- struct task_struct *thread;
- char *ptr;
-
- switch (remcom_in_buffer[1]) {
- case 'g':
- ptr = &remcom_in_buffer[2];
- kgdb_hex2long(&ptr, &ks->threadid);
- thread = getthread(ks->linux_regs, ks->threadid);
- if (!thread && ks->threadid > 0) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_usethread = thread;
- ks->kgdb_usethreadid = ks->threadid;
- strcpy(remcom_out_buffer, "OK");
- break;
- case 'c':
- ptr = &remcom_in_buffer[2];
- kgdb_hex2long(&ptr, &ks->threadid);
- if (!ks->threadid) {
- kgdb_contthread = NULL;
- } else {
- thread = getthread(ks->linux_regs, ks->threadid);
- if (!thread && ks->threadid > 0) {
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_contthread = thread;
- }
- strcpy(remcom_out_buffer, "OK");
- break;
- }
-}
-
-/* Handle the 'T' thread query packets */
-static void gdb_cmd_thread(struct kgdb_state *ks)
-{
- char *ptr = &remcom_in_buffer[1];
- struct task_struct *thread;
-
- kgdb_hex2long(&ptr, &ks->threadid);
- thread = getthread(ks->linux_regs, ks->threadid);
- if (thread)
- strcpy(remcom_out_buffer, "OK");
- else
- error_packet(remcom_out_buffer, -EINVAL);
-}
-
-/* Handle the 'z' or 'Z' breakpoint remove or set packets */
-static void gdb_cmd_break(struct kgdb_state *ks)
-{
- /*
- * Since GDB-5.3, it's been drafted that '0' is a software
- * breakpoint, '1' is a hardware breakpoint, so let's do that.
- */
- char *bpt_type = &remcom_in_buffer[1];
- char *ptr = &remcom_in_buffer[2];
- unsigned long addr;
- unsigned long length;
- int error = 0;
-
- if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
- /* Unsupported */
- if (*bpt_type > '4')
- return;
- } else {
- if (*bpt_type != '0' && *bpt_type != '1')
- /* Unsupported. */
- return;
- }
-
- /*
- * Test if this is a hardware breakpoint, and
- * if we support it:
- */
- if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
- /* Unsupported. */
- return;
-
- if (*(ptr++) != ',') {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
- if (!kgdb_hex2long(&ptr, &addr)) {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
- if (*(ptr++) != ',' ||
- !kgdb_hex2long(&ptr, &length)) {
- error_packet(remcom_out_buffer, -EINVAL);
- return;
- }
-
- if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
- error = kgdb_set_sw_break(addr);
- else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
- error = kgdb_remove_sw_break(addr);
- else if (remcom_in_buffer[0] == 'Z')
- error = arch_kgdb_ops.set_hw_breakpoint(addr,
- (int)length, *bpt_type - '0');
- else if (remcom_in_buffer[0] == 'z')
- error = arch_kgdb_ops.remove_hw_breakpoint(addr,
- (int) length, *bpt_type - '0');
-
- if (error == 0)
- strcpy(remcom_out_buffer, "OK");
- else
- error_packet(remcom_out_buffer, error);
-}
-
-/* Handle the 'C' signal / exception passing packets */
-static int gdb_cmd_exception_pass(struct kgdb_state *ks)
-{
- /* C09 == pass exception
- * C15 == detach kgdb, pass exception
- */
- if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
-
- ks->pass_exception = 1;
- remcom_in_buffer[0] = 'c';
-
- } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
-
- ks->pass_exception = 1;
- remcom_in_buffer[0] = 'D';
- remove_all_break();
- kgdb_connected = 0;
- return 1;
-
- } else {
- kgdb_msg_write("KGDB only knows signal 9 (pass)"
- " and 15 (pass and disconnect)\n"
- "Executing a continue without signal passing\n", 0);
- remcom_in_buffer[0] = 'c';
- }
-
- /* Indicate fall through */
- return -1;
-}
-
-/*
- * This function performs all gdbserial command procesing
- */
-static int gdb_serial_stub(struct kgdb_state *ks)
-{
- int error = 0;
- int tmp;
-
- /* Clear the out buffer. */
- memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
- if (kgdb_connected) {
- unsigned char thref[8];
- char *ptr;
-
- /* Reply to host that an exception has occurred */
- ptr = remcom_out_buffer;
- *ptr++ = 'T';
- ptr = pack_hex_byte(ptr, ks->signo);
- ptr += strlen(strcpy(ptr, "thread:"));
- int_to_threadref(thref, shadow_pid(current->pid));
- ptr = pack_threadid(ptr, thref);
- *ptr++ = ';';
- put_packet(remcom_out_buffer);
- }
-
- kgdb_usethread = kgdb_info[ks->cpu].task;
- ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
- ks->pass_exception = 0;
-
- while (1) {
- error = 0;
-
- /* Clear the out buffer. */
- memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
-
- get_packet(remcom_in_buffer);
-
- switch (remcom_in_buffer[0]) {
- case '?': /* gdbserial status */
- gdb_cmd_status(ks);
- break;
- case 'g': /* return the value of the CPU registers */
- gdb_cmd_getregs(ks);
- break;
- case 'G': /* set the value of the CPU registers - return OK */
- gdb_cmd_setregs(ks);
- break;
- case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
- gdb_cmd_memread(ks);
- break;
- case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
- gdb_cmd_memwrite(ks);
- break;
- case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
- gdb_cmd_binwrite(ks);
- break;
- /* kill or detach. KGDB should treat this like a
- * continue.
- */
- case 'D': /* Debugger detach */
- case 'k': /* Debugger detach via kill */
- gdb_cmd_detachkill(ks);
- goto default_handle;
- case 'R': /* Reboot */
- if (gdb_cmd_reboot(ks))
- goto default_handle;
- break;
- case 'q': /* query command */
- gdb_cmd_query(ks);
- break;
- case 'H': /* task related */
- gdb_cmd_task(ks);
- break;
- case 'T': /* Query thread status */
- gdb_cmd_thread(ks);
- break;
- case 'z': /* Break point remove */
- case 'Z': /* Break point set */
- gdb_cmd_break(ks);
- break;
- case 'C': /* Exception passing */
- tmp = gdb_cmd_exception_pass(ks);
- if (tmp > 0)
- goto default_handle;
- if (tmp == 0)
- break;
- /* Fall through on tmp < 0 */
- case 'c': /* Continue packet */
- case 's': /* Single step packet */
- if (kgdb_contthread && kgdb_contthread != current) {
- /* Can't switch threads in kgdb */
- error_packet(remcom_out_buffer, -EINVAL);
- break;
- }
- kgdb_activate_sw_breakpoints();
- /* Fall through to default processing */
- default:
-default_handle:
- error = kgdb_arch_handle_exception(ks->ex_vector,
- ks->signo,
- ks->err_code,
- remcom_in_buffer,
- remcom_out_buffer,
- ks->linux_regs);
- /*
- * Leave cmd processing on error, detach,
- * kill, continue, or single step.
- */
- if (error >= 0 || remcom_in_buffer[0] == 'D' ||
- remcom_in_buffer[0] == 'k') {
- error = 0;
- goto kgdb_exit;
- }
-
- }
-
- /* reply to the request */
- put_packet(remcom_out_buffer);
- }
-
-kgdb_exit:
- if (ks->pass_exception)
- error = 1;
- return error;
-}
-
static int kgdb_reenter_check(struct kgdb_state *ks)
{
unsigned long addr;
@@ -1375,17 +461,17 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
* user because the user planted a breakpoint in a place that
* KGDB needs in order to function.
*/
- if (kgdb_remove_sw_break(addr) == 0) {
+ if (dbg_remove_sw_break(addr) == 0) {
exception_level = 0;
kgdb_skipexception(ks->ex_vector, ks->linux_regs);
- kgdb_activate_sw_breakpoints();
+ dbg_activate_sw_breakpoints();
printk(KERN_CRIT "KGDB: re-enter error: breakpoint removed %lx\n",
addr);
WARN_ON_ONCE(1);
return 1;
}
- remove_all_break();
+ dbg_remove_all_break();
kgdb_skipexception(ks->ex_vector, ks->linux_regs);
if (exception_level > 1) {
@@ -1462,7 +548,7 @@ acquirelock:
if (!kgdb_io_ready(1)) {
error = 1;
- goto kgdb_restore; /* No I/O connection, so resume the system */
+ goto kgdb_restore; /* No I/O connection, resume the system */
}
/*
@@ -1472,8 +558,8 @@ acquirelock:
goto kgdb_restore;
/* Call the I/O driver's pre_exception routine */
- if (kgdb_io_ops->pre_exception)
- kgdb_io_ops->pre_exception();
+ if (dbg_io_ops->pre_exception)
+ dbg_io_ops->pre_exception();
kgdb_info[ks->cpu].debuggerinfo = ks->linux_regs;
kgdb_info[ks->cpu].task = current;
@@ -1523,8 +609,8 @@ acquirelock:
error = gdb_serial_stub(ks);
/* Call the I/O driver's post_exception routine */
- if (kgdb_io_ops->post_exception)
- kgdb_io_ops->post_exception();
+ if (dbg_io_ops->post_exception)
+ dbg_io_ops->post_exception();
kgdb_info[ks->cpu].debuggerinfo = NULL;
kgdb_info[ks->cpu].task = NULL;
@@ -1584,7 +670,7 @@ static void kgdb_console_write(struct console *co, const char *s,
return;
local_irq_save(flags);
- kgdb_msg_write(s, count);
+ gdbstub_msg_write(s, count);
local_irq_restore(flags);
}
@@ -1596,9 +682,9 @@ static struct console kgdbcons = {
};
#ifdef CONFIG_MAGIC_SYSRQ
-static void sysrq_handle_gdb(int key, struct tty_struct *tty)
+static void sysrq_handle_dbg(int key, struct tty_struct *tty)
{
- if (!kgdb_io_ops) {
+ if (!dbg_io_ops) {
printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
return;
}
@@ -1608,8 +694,8 @@ static void sysrq_handle_gdb(int key, struct tty_struct *tty)
kgdb_breakpoint();
}
-static struct sysrq_key_op sysrq_gdb_op = {
- .handler = sysrq_handle_gdb,
+static struct sysrq_key_op sysrq_dbg_op = {
+ .handler = sysrq_handle_dbg,
.help_msg = "debug(G)",
.action_msg = "DEBUG",
};
@@ -1621,7 +707,7 @@ static void kgdb_register_callbacks(void)
kgdb_io_module_registered = 1;
kgdb_arch_init();
#ifdef CONFIG_MAGIC_SYSRQ
- register_sysrq_key('g', &sysrq_gdb_op);
+ register_sysrq_key('g', &sysrq_dbg_op);
#endif
if (kgdb_use_con && !kgdb_con_registered) {
register_console(&kgdbcons);
@@ -1641,7 +727,7 @@ static void kgdb_unregister_callbacks(void)
kgdb_io_module_registered = 0;
kgdb_arch_exit();
#ifdef CONFIG_MAGIC_SYSRQ
- unregister_sysrq_key('g', &sysrq_gdb_op);
+ unregister_sysrq_key('g', &sysrq_dbg_op);
#endif
if (kgdb_con_registered) {
unregister_console(&kgdbcons);
@@ -1660,17 +746,17 @@ static void kgdb_initial_breakpoint(void)
/**
* kgdb_register_io_module - register KGDB IO module
- * @new_kgdb_io_ops: the io ops vector
+ * @new_dbg_io_ops: the io ops vector
*
* Register it with the KGDB core.
*/
-int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops)
+int kgdb_register_io_module(struct kgdb_io *new_dbg_io_ops)
{
int err;
spin_lock(&kgdb_registration_lock);
- if (kgdb_io_ops) {
+ if (dbg_io_ops) {
spin_unlock(&kgdb_registration_lock);
printk(KERN_ERR "kgdb: Another I/O driver is already "
@@ -1678,20 +764,20 @@ int kgdb_register_io_module(struct kgdb_io *new_kgdb_io_ops)
return -EBUSY;
}
- if (new_kgdb_io_ops->init) {
- err = new_kgdb_io_ops->init();
+ if (new_dbg_io_ops->init) {
+ err = new_dbg_io_ops->init();
if (err) {
spin_unlock(&kgdb_registration_lock);
return err;
}
}
- kgdb_io_ops = new_kgdb_io_ops;
+ dbg_io_ops = new_dbg_io_ops;
spin_unlock(&kgdb_registration_lock);
printk(KERN_INFO "kgdb: Registered I/O driver %s.\n",
- new_kgdb_io_ops->name);
+ new_dbg_io_ops->name);
/* Arm KGDB now. */
kgdb_register_callbacks();
@@ -1705,11 +791,11 @@ EXPORT_SYMBOL_GPL(kgdb_register_io_module);
/**
* kkgdb_unregister_io_module - unregister KGDB IO module
- * @old_kgdb_io_ops: the io ops vector
+ * @old_dbg_io_ops: the io ops vector
*
* Unregister it with the KGDB core.
*/
-void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops)
+void kgdb_unregister_io_module(struct kgdb_io *old_dbg_io_ops)
{
BUG_ON(kgdb_connected);
@@ -1721,14 +807,14 @@ void kgdb_unregister_io_module(struct kgdb_io *old_kgdb_io_ops)
spin_lock(&kgdb_registration_lock);
- WARN_ON_ONCE(kgdb_io_ops != old_kgdb_io_ops);
- kgdb_io_ops = NULL;
+ WARN_ON_ONCE(dbg_io_ops != old_dbg_io_ops);
+ dbg_io_ops = NULL;
spin_unlock(&kgdb_registration_lock);
printk(KERN_INFO
"kgdb: Unregistered I/O driver %s, debugger disabled.\n",
- old_kgdb_io_ops->name);
+ old_dbg_io_ops->name);
}
EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h
new file mode 100644
index 0000000..ebfd5bb
--- /dev/null
+++ b/kernel/debug/debug_core.h
@@ -0,0 +1,49 @@
+/*
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _DEBUG_CORE_H_
+#define _DEBUG_CORE_H_
+/*
+ * These are the private implementation headers between the kernel
+ * debugger core and the debugger front end code.
+ */
+
+/* kernel debug core data structures */
+struct kgdb_state {
+ int ex_vector;
+ int signo;
+ int err_code;
+ int cpu;
+ int pass_exception;
+ unsigned long thr_query;
+ unsigned long threadid;
+ long kgdb_usethreadid;
+ struct pt_regs *linux_regs;
+};
+
+struct debuggerinfo_struct {
+ void *debuggerinfo;
+ struct task_struct *task;
+};
+
+extern struct debuggerinfo_struct kgdb_info[];
+extern struct kgdb_io *dbg_io_ops;
+
+/* kernel debug core break point routines */
+extern int dbg_remove_all_break(void);
+extern int dbg_set_sw_break(unsigned long addr);
+extern int dbg_remove_sw_break(unsigned long addr);
+extern int dbg_activate_sw_breakpoints(void);
+
+/* gdbstub interface functions */
+extern int gdb_serial_stub(struct kgdb_state *ks);
+extern void gdbstub_msg_write(const char *s, int len);
+
+#endif /* _DEBUG_CORE_H_ */
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
new file mode 100644
index 0000000..ab29bce
--- /dev/null
+++ b/kernel/debug/gdbstub.c
@@ -0,0 +1,939 @@
+/*
+ * Kernel Debug Core
+ *
+ * Maintainer: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (C) 2000-2001 VERITAS Software Corporation.
+ * Copyright (C) 2002-2004 Timesys Corporation
+ * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com>
+ * Copyright (C) 2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org>
+ * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd.
+ * Copyright (C) 2005-2009 Wind River Systems, Inc.
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ * Contributors at various stages not listed above:
+ * Jason Wessel ( jason.wessel@windriver.com )
+ * George Anzinger <george@mvista.com>
+ * Anurekh Saxena (anurekh.saxena@timesys.com)
+ * Lake Stevens Instrument Division (Glenn Engel)
+ * Jim Kingdon, Cygnus Support.
+ *
+ * Original KGDB stub: David Grothe <dave@gcom.com>,
+ * Tigran Aivazian <tigran@sco.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/kgdb.h>
+#include <linux/reboot.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/unaligned.h>
+#include "debug_core.h"
+
+#define KGDB_MAX_THREAD_QUERY 17
+
+/* Our I/O buffers. */
+static char remcom_in_buffer[BUFMAX];
+static char remcom_out_buffer[BUFMAX];
+
+/* Storage for the registers, in GDB format. */
+static unsigned long gdb_regs[(NUMREGBYTES +
+ sizeof(unsigned long) - 1) /
+ sizeof(unsigned long)];
+
+/*
+ * GDB remote protocol parser:
+ */
+
+static int hex(char ch)
+{
+ if ((ch >= 'a') && (ch <= 'f'))
+ return ch - 'a' + 10;
+ if ((ch >= '0') && (ch <= '9'))
+ return ch - '0';
+ if ((ch >= 'A') && (ch <= 'F'))
+ return ch - 'A' + 10;
+ return -1;
+}
+
+/* scan for the sequence $<data>#<checksum> */
+static void get_packet(char *buffer)
+{
+ unsigned char checksum;
+ unsigned char xmitcsum;
+ int count;
+ char ch;
+
+ do {
+ /*
+ * Spin and wait around for the start character, ignore all
+ * other characters:
+ */
+ while ((ch = (dbg_io_ops->read_char())) != '$')
+ /* nothing */;
+
+ kgdb_connected = 1;
+ checksum = 0;
+ xmitcsum = -1;
+
+ count = 0;
+
+ /*
+ * now, read until a # or end of buffer is found:
+ */
+ while (count < (BUFMAX - 1)) {
+ ch = dbg_io_ops->read_char();
+ if (ch == '#')
+ break;
+ checksum = checksum + ch;
+ buffer[count] = ch;
+ count = count + 1;
+ }
+ buffer[count] = 0;
+
+ if (ch == '#') {
+ xmitcsum = hex(dbg_io_ops->read_char()) << 4;
+ xmitcsum += hex(dbg_io_ops->read_char());
+
+ if (checksum != xmitcsum)
+ /* failed checksum */
+ dbg_io_ops->write_char('-');
+ else
+ /* successful transfer */
+ dbg_io_ops->write_char('+');
+ if (dbg_io_ops->flush)
+ dbg_io_ops->flush();
+ }
+ } while (checksum != xmitcsum);
+}
+
+/*
+ * Send the packet in buffer.
+ * Check for gdb connection if asked for.
+ */
+static void put_packet(char *buffer)
+{
+ unsigned char checksum;
+ int count;
+ char ch;
+
+ /*
+ * $<packet info>#<checksum>.
+ */
+ while (1) {
+ dbg_io_ops->write_char('$');
+ checksum = 0;
+ count = 0;
+
+ while ((ch = buffer[count])) {
+ dbg_io_ops->write_char(ch);
+ checksum += ch;
+ count++;
+ }
+
+ dbg_io_ops->write_char('#');
+ dbg_io_ops->write_char(hex_asc_hi(checksum));
+ dbg_io_ops->write_char(hex_asc_lo(checksum));
+ if (dbg_io_ops->flush)
+ dbg_io_ops->flush();
+
+ /* Now see what we get in reply. */
+ ch = dbg_io_ops->read_char();
+
+ if (ch == 3)
+ ch = dbg_io_ops->read_char();
+
+ /* If we get an ACK, we are done. */
+ if (ch == '+')
+ return;
+
+ /*
+ * If we get the start of another packet, this means
+ * that GDB is attempting to reconnect. We will NAK
+ * the packet being sent, and stop trying to send this
+ * packet.
+ */
+ if (ch == '$') {
+ dbg_io_ops->write_char('-');
+ if (dbg_io_ops->flush)
+ dbg_io_ops->flush();
+ return;
+ }
+ }
+}
+
+static char gdbmsgbuf[BUFMAX + 1];
+
+void gdbstub_msg_write(const char *s, int len)
+{
+ char *bufptr;
+ int wcount;
+ int i;
+
+ /* 'O'utput */
+ gdbmsgbuf[0] = 'O';
+
+ /* Fill and send buffers... */
+ while (len > 0) {
+ bufptr = gdbmsgbuf + 1;
+
+ /* Calculate how many this time */
+ if ((len << 1) > (BUFMAX - 2))
+ wcount = (BUFMAX - 2) >> 1;
+ else
+ wcount = len;
+
+ /* Pack in hex chars */
+ for (i = 0; i < wcount; i++)
+ bufptr = pack_hex_byte(bufptr, s[i]);
+ *bufptr = '\0';
+
+ /* Move up */
+ s += wcount;
+ len -= wcount;
+
+ /* Write packet */
+ put_packet(gdbmsgbuf);
+ }
+}
+
+/*
+ * Convert the memory pointed to by mem into hex, placing result in
+ * buf. Return a pointer to the last char put in buf (null). May
+ * return an error.
+ */
+int kgdb_mem2hex(char *mem, char *buf, int count)
+{
+ char *tmp;
+ int err;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory copy. Hex conversion will work against this one.
+ */
+ tmp = buf + count;
+
+ err = probe_kernel_read(tmp, mem, count);
+ if (!err) {
+ while (count > 0) {
+ buf = pack_hex_byte(buf, *tmp);
+ tmp++;
+ count--;
+ }
+
+ *buf = 0;
+ }
+
+ return err;
+}
+
+/*
+ * Convert the hex array pointed to by buf into binary to be placed in
+ * mem. Return a pointer to the character AFTER the last byte
+ * written. May return an error.
+ */
+int kgdb_hex2mem(char *buf, char *mem, int count)
+{
+ char *tmp_raw;
+ char *tmp_hex;
+
+ /*
+ * We use the upper half of buf as an intermediate buffer for the
+ * raw memory that is converted from hex.
+ */
+ tmp_raw = buf + count * 2;
+
+ tmp_hex = tmp_raw - 1;
+ while (tmp_hex >= buf) {
+ tmp_raw--;
+ *tmp_raw = hex(*tmp_hex--);
+ *tmp_raw |= hex(*tmp_hex--) << 4;
+ }
+
+ return probe_kernel_write(mem, tmp_raw, count);
+}
+
+/*
+ * While we find nice hex chars, build a long_val.
+ * Return number of chars processed.
+ */
+int kgdb_hex2long(char **ptr, unsigned long *long_val)
+{
+ int hex_val;
+ int num = 0;
+ int negate = 0;
+
+ *long_val = 0;
+
+ if (**ptr == '-') {
+ negate = 1;
+ (*ptr)++;
+ }
+ while (**ptr) {
+ hex_val = hex(**ptr);
+ if (hex_val < 0)
+ break;
+
+ *long_val = (*long_val << 4) | hex_val;
+ num++;
+ (*ptr)++;
+ }
+
+ if (negate)
+ *long_val = -*long_val;
+
+ return num;
+}
+
+/*
+ * Copy the binary array pointed to by buf into mem. Fix $, #, and
+ * 0x7d escaped with 0x7d. Return a pointer to the character after
+ * the last byte written.
+ */
+static int kgdb_ebin2mem(char *buf, char *mem, int count)
+{
+ int err = 0;
+ char c;
+
+ while (count-- > 0) {
+ c = *buf++;
+ if (c == 0x7d)
+ c = *buf++ ^ 0x20;
+
+ err = probe_kernel_write(mem, &c, 1);
+ if (err)
+ break;
+
+ mem++;
+ }
+
+ return err;
+}
+
+/* Write memory due to an 'M' or 'X' packet. */
+static int write_mem_msg(int binary)
+{
+ char *ptr = &remcom_in_buffer[1];
+ unsigned long addr;
+ unsigned long length;
+ int err;
+
+ if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' &&
+ kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') {
+ if (binary)
+ err = kgdb_ebin2mem(ptr, (char *)addr, length);
+ else
+ err = kgdb_hex2mem(ptr, (char *)addr, length);
+ if (err)
+ return err;
+ if (CACHE_FLUSH_IS_SAFE)
+ flush_icache_range(addr, addr + length);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static void error_packet(char *pkt, int error)
+{
+ error = -error;
+ pkt[0] = 'E';
+ pkt[1] = hex_asc[(error / 10)];
+ pkt[2] = hex_asc[(error % 10)];
+ pkt[3] = '\0';
+}
+
+/*
+ * Thread ID accessors. We represent a flat TID space to GDB, where
+ * the per CPU idle threads (which under Linux all have PID 0) are
+ * remapped to negative TIDs.
+ */
+
+#define BUF_THREAD_ID_SIZE 16
+
+static char *pack_threadid(char *pkt, unsigned char *id)
+{
+ char *limit;
+
+ limit = pkt + BUF_THREAD_ID_SIZE;
+ while (pkt < limit)
+ pkt = pack_hex_byte(pkt, *id++);
+
+ return pkt;
+}
+
+static void int_to_threadref(unsigned char *id, int value)
+{
+ unsigned char *scan;
+ int i = 4;
+
+ scan = (unsigned char *)id;
+ while (i--)
+ *scan++ = 0;
+ put_unaligned_be32(value, scan);
+}
+
+static struct task_struct *getthread(struct pt_regs *regs, int tid)
+{
+ /*
+ * Non-positive TIDs are remapped to the cpu shadow information
+ */
+ if (tid == 0 || tid == -1)
+ tid = -atomic_read(&kgdb_active) - 2;
+ if (tid < -1 && tid > -NR_CPUS - 2) {
+ if (kgdb_info[-tid - 2].task)
+ return kgdb_info[-tid - 2].task;
+ else
+ return idle_task(-tid - 2);
+ }
+ if (tid <= 0) {
+ printk(KERN_ERR "KGDB: Internal thread select error\n");
+ dump_stack();
+ return NULL;
+ }
+
+ /*
+ * find_task_by_pid_ns() does not take the tasklist lock anymore
+ * but is nicely RCU locked - hence is a pretty resilient
+ * thing to use:
+ */
+ return find_task_by_pid_ns(tid, &init_pid_ns);
+}
+
+
+/*
+ * Remap normal tasks to their real PID,
+ * CPU shadow threads are mapped to -CPU - 2
+ */
+static inline int shadow_pid(int realpid)
+{
+ if (realpid)
+ return realpid;
+
+ return -raw_smp_processor_id() - 2;
+}
+
+/*
+ * All the functions that start with gdb_cmd are the various
+ * operations to implement the handlers for the gdbserial protocol
+ * where KGDB is communicating with an external debugger
+ */
+
+/* Handle the '?' status packets */
+static void gdb_cmd_status(struct kgdb_state *ks)
+{
+ /*
+ * We know that this packet is only sent
+ * during initial connect. So to be safe,
+ * we clear out our breakpoints now in case
+ * GDB is reconnecting.
+ */
+ dbg_remove_all_break();
+
+ remcom_out_buffer[0] = 'S';
+ pack_hex_byte(&remcom_out_buffer[1], ks->signo);
+}
+
+/* Handle the 'g' get registers request */
+static void gdb_cmd_getregs(struct kgdb_state *ks)
+{
+ struct task_struct *thread;
+ void *local_debuggerinfo;
+ int i;
+
+ thread = kgdb_usethread;
+ if (!thread) {
+ thread = kgdb_info[ks->cpu].task;
+ local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo;
+ } else {
+ local_debuggerinfo = NULL;
+ for_each_online_cpu(i) {
+ /*
+ * Try to find the task on some other
+ * or possibly this node if we do not
+ * find the matching task then we try
+ * to approximate the results.
+ */
+ if (thread == kgdb_info[i].task)
+ local_debuggerinfo = kgdb_info[i].debuggerinfo;
+ }
+ }
+
+ /*
+ * All threads that don't have debuggerinfo should be
+ * in schedule() sleeping, since all other CPUs
+ * are in kgdb_wait, and thus have debuggerinfo.
+ */
+ if (local_debuggerinfo) {
+ pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo);
+ } else {
+ /*
+ * Pull stuff saved during switch_to; nothing
+ * else is accessible (or even particularly
+ * relevant).
+ *
+ * This should be enough for a stack trace.
+ */
+ sleeping_thread_to_gdb_regs(gdb_regs, thread);
+ }
+ kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES);
+}
+
+/* Handle the 'G' set registers request */
+static void gdb_cmd_setregs(struct kgdb_state *ks)
+{
+ kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES);
+
+ if (kgdb_usethread && kgdb_usethread != current) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ } else {
+ gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs);
+ strcpy(remcom_out_buffer, "OK");
+ }
+}
+
+/* Handle the 'm' memory read bytes */
+static void gdb_cmd_memread(struct kgdb_state *ks)
+{
+ char *ptr = &remcom_in_buffer[1];
+ unsigned long length;
+ unsigned long addr;
+ int err;
+
+ if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' &&
+ kgdb_hex2long(&ptr, &length) > 0) {
+ err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length);
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ } else {
+ error_packet(remcom_out_buffer, -EINVAL);
+ }
+}
+
+/* Handle the 'M' memory write bytes */
+static void gdb_cmd_memwrite(struct kgdb_state *ks)
+{
+ int err = write_mem_msg(0);
+
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ else
+ strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'X' memory binary write bytes */
+static void gdb_cmd_binwrite(struct kgdb_state *ks)
+{
+ int err = write_mem_msg(1);
+
+ if (err)
+ error_packet(remcom_out_buffer, err);
+ else
+ strcpy(remcom_out_buffer, "OK");
+}
+
+/* Handle the 'D' or 'k', detach or kill packets */
+static void gdb_cmd_detachkill(struct kgdb_state *ks)
+{
+ int error;
+
+ /* The detach case */
+ if (remcom_in_buffer[0] == 'D') {
+ error = dbg_remove_all_break();
+ if (error < 0) {
+ error_packet(remcom_out_buffer, error);
+ } else {
+ strcpy(remcom_out_buffer, "OK");
+ kgdb_connected = 0;
+ }
+ put_packet(remcom_out_buffer);
+ } else {
+ /*
+ * Assume the kill case, with no exit code checking,
+ * trying to force detach the debugger:
+ */
+ dbg_remove_all_break();
+ kgdb_connected = 0;
+ }
+}
+
+/* Handle the 'R' reboot packets */
+static int gdb_cmd_reboot(struct kgdb_state *ks)
+{
+ /* For now, only honor R0 */
+ if (strcmp(remcom_in_buffer, "R0") == 0) {
+ printk(KERN_CRIT "Executing emergency reboot\n");
+ strcpy(remcom_out_buffer, "OK");
+ put_packet(remcom_out_buffer);
+
+ /*
+ * Execution should not return from
+ * machine_emergency_restart()
+ */
+ machine_emergency_restart();
+ kgdb_connected = 0;
+
+ return 1;
+ }
+ return 0;
+}
+
+/* Handle the 'q' query packets */
+static void gdb_cmd_query(struct kgdb_state *ks)
+{
+ struct task_struct *g;
+ struct task_struct *p;
+ unsigned char thref[8];
+ char *ptr;
+ int i;
+ int cpu;
+ int finished = 0;
+
+ switch (remcom_in_buffer[1]) {
+ case 's':
+ case 'f':
+ if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+
+ i = 0;
+ remcom_out_buffer[0] = 'm';
+ ptr = remcom_out_buffer + 1;
+ if (remcom_in_buffer[1] == 'f') {
+ /* Each cpu is a shadow thread */
+ for_each_online_cpu(cpu) {
+ ks->thr_query = 0;
+ int_to_threadref(thref, -cpu - 2);
+ pack_threadid(ptr, thref);
+ ptr += BUF_THREAD_ID_SIZE;
+ *(ptr++) = ',';
+ i++;
+ }
+ }
+
+ do_each_thread(g, p) {
+ if (i >= ks->thr_query && !finished) {
+ int_to_threadref(thref, p->pid);
+ pack_threadid(ptr, thref);
+ ptr += BUF_THREAD_ID_SIZE;
+ *(ptr++) = ',';
+ ks->thr_query++;
+ if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0)
+ finished = 1;
+ }
+ i++;
+ } while_each_thread(g, p);
+
+ *(--ptr) = '\0';
+ break;
+
+ case 'C':
+ /* Current thread id */
+ strcpy(remcom_out_buffer, "QC");
+ ks->threadid = shadow_pid(current->pid);
+ int_to_threadref(thref, ks->threadid);
+ pack_threadid(remcom_out_buffer + 2, thref);
+ break;
+ case 'T':
+ if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ ks->threadid = 0;
+ ptr = remcom_in_buffer + 17;
+ kgdb_hex2long(&ptr, &ks->threadid);
+ if (!getthread(ks->linux_regs, ks->threadid)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ if ((int)ks->threadid > 0) {
+ kgdb_mem2hex(getthread(ks->linux_regs,
+ ks->threadid)->comm,
+ remcom_out_buffer, 16);
+ } else {
+ static char tmpstr[23 + BUF_THREAD_ID_SIZE];
+
+ sprintf(tmpstr, "shadowCPU%d",
+ (int)(-ks->threadid - 2));
+ kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
+ }
+ break;
+ }
+}
+
+/* Handle the 'H' task query packets */
+static void gdb_cmd_task(struct kgdb_state *ks)
+{
+ struct task_struct *thread;
+ char *ptr;
+
+ switch (remcom_in_buffer[1]) {
+ case 'g':
+ ptr = &remcom_in_buffer[2];
+ kgdb_hex2long(&ptr, &ks->threadid);
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (!thread && ks->threadid > 0) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ kgdb_usethread = thread;
+ ks->kgdb_usethreadid = ks->threadid;
+ strcpy(remcom_out_buffer, "OK");
+ break;
+ case 'c':
+ ptr = &remcom_in_buffer[2];
+ kgdb_hex2long(&ptr, &ks->threadid);
+ if (!ks->threadid) {
+ kgdb_contthread = NULL;
+ } else {
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (!thread && ks->threadid > 0) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ kgdb_contthread = thread;
+ }
+ strcpy(remcom_out_buffer, "OK");
+ break;
+ }
+}
+
+/* Handle the 'T' thread query packets */
+static void gdb_cmd_thread(struct kgdb_state *ks)
+{
+ char *ptr = &remcom_in_buffer[1];
+ struct task_struct *thread;
+
+ kgdb_hex2long(&ptr, &ks->threadid);
+ thread = getthread(ks->linux_regs, ks->threadid);
+ if (thread)
+ strcpy(remcom_out_buffer, "OK");
+ else
+ error_packet(remcom_out_buffer, -EINVAL);
+}
+
+/* Handle the 'z' or 'Z' breakpoint remove or set packets */
+static void gdb_cmd_break(struct kgdb_state *ks)
+{
+ /*
+ * Since GDB-5.3, it's been drafted that '0' is a software
+ * breakpoint, '1' is a hardware breakpoint, so let's do that.
+ */
+ char *bpt_type = &remcom_in_buffer[1];
+ char *ptr = &remcom_in_buffer[2];
+ unsigned long addr;
+ unsigned long length;
+ int error = 0;
+
+ if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') {
+ /* Unsupported */
+ if (*bpt_type > '4')
+ return;
+ } else {
+ if (*bpt_type != '0' && *bpt_type != '1')
+ /* Unsupported. */
+ return;
+ }
+
+ /*
+ * Test if this is a hardware breakpoint, and
+ * if we support it:
+ */
+ if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT))
+ /* Unsupported. */
+ return;
+
+ if (*(ptr++) != ',') {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+ if (!kgdb_hex2long(&ptr, &addr)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+ if (*(ptr++) != ',' ||
+ !kgdb_hex2long(&ptr, &length)) {
+ error_packet(remcom_out_buffer, -EINVAL);
+ return;
+ }
+
+ if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0')
+ error = dbg_set_sw_break(addr);
+ else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0')
+ error = dbg_remove_sw_break(addr);
+ else if (remcom_in_buffer[0] == 'Z')
+ error = arch_kgdb_ops.set_hw_breakpoint(addr,
+ (int)length, *bpt_type - '0');
+ else if (remcom_in_buffer[0] == 'z')
+ error = arch_kgdb_ops.remove_hw_breakpoint(addr,
+ (int) length, *bpt_type - '0');
+
+ if (error == 0)
+ strcpy(remcom_out_buffer, "OK");
+ else
+ error_packet(remcom_out_buffer, error);
+}
+
+/* Handle the 'C' signal / exception passing packets */
+static int gdb_cmd_exception_pass(struct kgdb_state *ks)
+{
+ /* C09 == pass exception
+ * C15 == detach kgdb, pass exception
+ */
+ if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') {
+
+ ks->pass_exception = 1;
+ remcom_in_buffer[0] = 'c';
+
+ } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') {
+
+ ks->pass_exception = 1;
+ remcom_in_buffer[0] = 'D';
+ dbg_remove_all_break();
+ kgdb_connected = 0;
+ return 1;
+
+ } else {
+ gdbstub_msg_write("KGDB only knows signal 9 (pass)"
+ " and 15 (pass and disconnect)\n"
+ "Executing a continue without signal passing\n", 0);
+ remcom_in_buffer[0] = 'c';
+ }
+
+ /* Indicate fall through */
+ return -1;
+}
+
+/*
+ * This function performs all gdbserial command procesing
+ */
+int gdb_serial_stub(struct kgdb_state *ks)
+{
+ int error = 0;
+ int tmp;
+
+ /* Clear the out buffer. */
+ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+ if (kgdb_connected) {
+ unsigned char thref[8];
+ char *ptr;
+
+ /* Reply to host that an exception has occurred */
+ ptr = remcom_out_buffer;
+ *ptr++ = 'T';
+ ptr = pack_hex_byte(ptr, ks->signo);
+ ptr += strlen(strcpy(ptr, "thread:"));
+ int_to_threadref(thref, shadow_pid(current->pid));
+ ptr = pack_threadid(ptr, thref);
+ *ptr++ = ';';
+ put_packet(remcom_out_buffer);
+ }
+
+ kgdb_usethread = kgdb_info[ks->cpu].task;
+ ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid);
+ ks->pass_exception = 0;
+
+ while (1) {
+ error = 0;
+
+ /* Clear the out buffer. */
+ memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer));
+
+ get_packet(remcom_in_buffer);
+
+ switch (remcom_in_buffer[0]) {
+ case '?': /* gdbserial status */
+ gdb_cmd_status(ks);
+ break;
+ case 'g': /* return the value of the CPU registers */
+ gdb_cmd_getregs(ks);
+ break;
+ case 'G': /* set the value of the CPU registers - return OK */
+ gdb_cmd_setregs(ks);
+ break;
+ case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */
+ gdb_cmd_memread(ks);
+ break;
+ case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+ gdb_cmd_memwrite(ks);
+ break;
+ case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */
+ gdb_cmd_binwrite(ks);
+ break;
+ /* kill or detach. KGDB should treat this like a
+ * continue.
+ */
+ case 'D': /* Debugger detach */
+ case 'k': /* Debugger detach via kill */
+ gdb_cmd_detachkill(ks);
+ goto default_handle;
+ case 'R': /* Reboot */
+ if (gdb_cmd_reboot(ks))
+ goto default_handle;
+ break;
+ case 'q': /* query command */
+ gdb_cmd_query(ks);
+ break;
+ case 'H': /* task related */
+ gdb_cmd_task(ks);
+ break;
+ case 'T': /* Query thread status */
+ gdb_cmd_thread(ks);
+ break;
+ case 'z': /* Break point remove */
+ case 'Z': /* Break point set */
+ gdb_cmd_break(ks);
+ break;
+ case 'C': /* Exception passing */
+ tmp = gdb_cmd_exception_pass(ks);
+ if (tmp > 0)
+ goto default_handle;
+ if (tmp == 0)
+ break;
+ /* Fall through on tmp < 0 */
+ case 'c': /* Continue packet */
+ case 's': /* Single step packet */
+ if (kgdb_contthread && kgdb_contthread != current) {
+ /* Can't switch threads in kgdb */
+ error_packet(remcom_out_buffer, -EINVAL);
+ break;
+ }
+ dbg_activate_sw_breakpoints();
+ /* Fall through to default processing */
+ default:
+default_handle:
+ error = kgdb_arch_handle_exception(ks->ex_vector,
+ ks->signo,
+ ks->err_code,
+ remcom_in_buffer,
+ remcom_out_buffer,
+ ks->linux_regs);
+ /*
+ * Leave cmd processing on error, detach,
+ * kill, continue, or single step.
+ */
+ if (error >= 0 || remcom_in_buffer[0] == 'D' ||
+ remcom_in_buffer[0] == 'k') {
+ error = 0;
+ goto kgdb_exit;
+ }
+
+ }
+
+ /* reply to the request */
+ put_packet(remcom_out_buffer);
+ }
+
+kgdb_exit:
+ if (ks->pass_exception)
+ error = 1;
+ return error;
+}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 05/40] kgdb: eliminate kgdb_wait(), all cpus enter the same way
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (3 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 04/40] Separate the gdbstub from the debug core Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 06/40] kgdb,sparc: Add in kgdb_arch_set_pc for sparc Jason Wessel
` (35 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
This is a kgdb architectural change to have all the cpus (master or
slave) enter the same function.
A cpu that hits an exception (wants to be the master cpu) will call
kgdb_handle_exception() from the trap handler and then invoke a
kgdb_roundup_cpu() to synchronize the other cpus and bring them into
the kgdb_handle_exception() as well.
A slave cpu will enter kgdb_handle_exception() from the
kgdb_nmicallback() and set the exception state to note that the
processor is a slave.
Previously the salve cpu would have called kgdb_wait(). This change
allows the debug core to change cpus without resuming the system in
order to inspect arch specific cpu information.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/debug/debug_core.c | 158 +++++++++++++++++++++-----------------------
kernel/debug/debug_core.h | 7 ++
2 files changed, 82 insertions(+), 83 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index ad3caaa..91286e8 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -215,49 +215,6 @@ void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
}
/*
- * CPU debug state control:
- */
-
-#ifdef CONFIG_SMP
-static void kgdb_wait(struct pt_regs *regs)
-{
- unsigned long flags;
- int cpu;
-
- local_irq_save(flags);
- cpu = raw_smp_processor_id();
- kgdb_info[cpu].debuggerinfo = regs;
- kgdb_info[cpu].task = current;
- /*
- * Make sure the above info reaches the primary CPU before
- * our cpu_in_kgdb[] flag setting does:
- */
- smp_wmb();
- atomic_set(&cpu_in_kgdb[cpu], 1);
-
- /* Disable any cpu specific hw breakpoints */
- kgdb_disable_hw_debug(regs);
-
- /* Wait till primary CPU is done with debugging */
- while (atomic_read(&passive_cpu_wait[cpu]))
- cpu_relax();
-
- kgdb_info[cpu].debuggerinfo = NULL;
- kgdb_info[cpu].task = NULL;
-
- /* fix up hardware debug registers on local cpu */
- if (arch_kgdb_ops.correct_hw_break)
- arch_kgdb_ops.correct_hw_break();
-
- /* Signal the primary CPU that we are done: */
- atomic_set(&cpu_in_kgdb[cpu], 0);
- touch_softlockup_watchdog_sync();
- clocksource_touch_watchdog();
- local_irq_restore(flags);
-}
-#endif
-
-/*
* Some architectures need cache flushes when we set/clear a
* breakpoint:
*/
@@ -486,34 +443,12 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
return 1;
}
-/*
- * kgdb_handle_exception() - main entry point from a kernel exception
- *
- * Locking hierarchy:
- * interface locks, if any (begin_session)
- * kgdb lock (kgdb_active)
- */
-int
-kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
+static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
{
- struct kgdb_state kgdb_var;
- struct kgdb_state *ks = &kgdb_var;
unsigned long flags;
int sstep_tries = 100;
int error = 0;
int i, cpu;
-
- ks->cpu = raw_smp_processor_id();
- ks->ex_vector = evector;
- ks->signo = signo;
- ks->ex_vector = evector;
- ks->err_code = ecode;
- ks->kgdb_usethreadid = 0;
- ks->linux_regs = regs;
-
- if (kgdb_reenter_check(ks))
- return 0; /* Ouch, double exception ! */
-
acquirelock:
/*
* Interrupts will be restored by the 'trap return' code, except when
@@ -521,13 +456,42 @@ acquirelock:
*/
local_irq_save(flags);
- cpu = raw_smp_processor_id();
+ cpu = ks->cpu;
+ kgdb_info[cpu].debuggerinfo = regs;
+ kgdb_info[cpu].task = current;
+ /*
+ * Make sure the above info reaches the primary CPU before
+ * our cpu_in_kgdb[] flag setting does:
+ */
+ smp_wmb();
+ atomic_set(&cpu_in_kgdb[cpu], 1);
/*
- * Acquire the kgdb_active lock:
+ * CPU will loop if it is a slave or request to become a kgdb
+ * master cpu and acquire the kgdb_active lock:
*/
- while (atomic_cmpxchg(&kgdb_active, -1, cpu) != -1)
+ while (1) {
+ if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) {
+ if (atomic_cmpxchg(&kgdb_active, -1, cpu) == cpu)
+ break;
+ } else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) {
+ if (!atomic_read(&passive_cpu_wait[cpu]))
+ goto return_normal;
+ } else {
+return_normal:
+ /* Return to normal operation by executing any
+ * hw breakpoint fixup.
+ */
+ if (arch_kgdb_ops.correct_hw_break)
+ arch_kgdb_ops.correct_hw_break();
+ atomic_set(&cpu_in_kgdb[cpu], 0);
+ touch_softlockup_watchdog_sync();
+ clocksource_touch_watchdog();
+ local_irq_restore(flags);
+ return 0;
+ }
cpu_relax();
+ }
/*
* For single stepping, try to only enter on the processor
@@ -561,9 +525,6 @@ acquirelock:
if (dbg_io_ops->pre_exception)
dbg_io_ops->pre_exception();
- kgdb_info[ks->cpu].debuggerinfo = ks->linux_regs;
- kgdb_info[ks->cpu].task = current;
-
kgdb_disable_hw_debug(ks->linux_regs);
/*
@@ -575,12 +536,6 @@ acquirelock:
atomic_set(&passive_cpu_wait[i], 1);
}
- /*
- * spin_lock code is good enough as a barrier so we don't
- * need one here:
- */
- atomic_set(&cpu_in_kgdb[ks->cpu], 1);
-
#ifdef CONFIG_SMP
/* Signal the other CPUs to enter kgdb_wait() */
if ((!kgdb_single_step) && kgdb_do_roundup)
@@ -612,8 +567,6 @@ acquirelock:
if (dbg_io_ops->post_exception)
dbg_io_ops->post_exception();
- kgdb_info[ks->cpu].debuggerinfo = NULL;
- kgdb_info[ks->cpu].task = NULL;
atomic_set(&cpu_in_kgdb[ks->cpu], 0);
if (!kgdb_single_step) {
@@ -646,13 +599,52 @@ kgdb_restore:
return error;
}
+/*
+ * kgdb_handle_exception() - main entry point from a kernel exception
+ *
+ * Locking hierarchy:
+ * interface locks, if any (begin_session)
+ * kgdb lock (kgdb_active)
+ */
+int
+kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
+{
+ struct kgdb_state kgdb_var;
+ struct kgdb_state *ks = &kgdb_var;
+ int ret;
+
+ ks->cpu = raw_smp_processor_id();
+ ks->ex_vector = evector;
+ ks->signo = signo;
+ ks->ex_vector = evector;
+ ks->err_code = ecode;
+ ks->kgdb_usethreadid = 0;
+ ks->linux_regs = regs;
+
+ if (kgdb_reenter_check(ks))
+ return 0; /* Ouch, double exception ! */
+ kgdb_info[ks->cpu].exception_state |= DCPU_WANT_MASTER;
+ ret = kgdb_cpu_enter(ks, regs);
+ kgdb_info[ks->cpu].exception_state &= ~DCPU_WANT_MASTER;
+ return ret;
+}
+
int kgdb_nmicallback(int cpu, void *regs)
{
#ifdef CONFIG_SMP
+ struct kgdb_state kgdb_var;
+ struct kgdb_state *ks = &kgdb_var;
+
+ memset(ks, 0, sizeof(struct kgdb_state));
+ ks->cpu = cpu;
+ ks->linux_regs = regs;
+
if (!atomic_read(&cpu_in_kgdb[cpu]) &&
- atomic_read(&kgdb_active) != cpu &&
- atomic_read(&cpu_in_kgdb[atomic_read(&kgdb_active)])) {
- kgdb_wait((struct pt_regs *)regs);
+ atomic_read(&kgdb_active) != -1 &&
+ atomic_read(&kgdb_active) != cpu) {
+ kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE;
+ kgdb_cpu_enter(ks, regs);
+ kgdb_info[cpu].exception_state &= ~DCPU_IS_SLAVE;
return 0;
}
#endif
diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h
index ebfd5bb..a111cda 100644
--- a/kernel/debug/debug_core.h
+++ b/kernel/debug/debug_core.h
@@ -28,9 +28,16 @@ struct kgdb_state {
struct pt_regs *linux_regs;
};
+/* Exception state values */
+#define DCPU_WANT_MASTER 0x1 /* Waiting to become a master kgdb cpu */
+#define DCPU_NEXT_MASTER 0x2 /* Transition from one master cpu to another */
+#define DCPU_IS_SLAVE 0x4 /* Slave cpu enter exception */
+#define DCPU_SSTEP 0x8 /* CPU is single stepping */
+
struct debuggerinfo_struct {
void *debuggerinfo;
struct task_struct *task;
+ int exception_state;
};
extern struct debuggerinfo_struct kgdb_info[];
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 06/40] kgdb,sparc: Add in kgdb_arch_set_pc for sparc
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (4 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 05/40] kgdb: eliminate kgdb_wait(), all cpus enter the same way Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 07/40] kgdb,sh: update superh kgdb exception handling Jason Wessel
` (34 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
The new debug core api requires all architectures that use to debug
core to implement a function to set the program counter.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
---
arch/sparc/kernel/kgdb_32.c | 6 ++++++
arch/sparc/kernel/kgdb_64.c | 6 ++++++
2 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/sparc/kernel/kgdb_32.c b/arch/sparc/kernel/kgdb_32.c
index 04df4ed..539243b 100644
--- a/arch/sparc/kernel/kgdb_32.c
+++ b/arch/sparc/kernel/kgdb_32.c
@@ -158,6 +158,12 @@ void kgdb_arch_exit(void)
{
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->pc = ip;
+ regs->npc = regs->pc + 4;
+}
+
struct kgdb_arch arch_kgdb_ops = {
/* Breakpoint instruction: ta 0x7d */
.gdb_bpt_instr = { 0x91, 0xd0, 0x20, 0x7d },
diff --git a/arch/sparc/kernel/kgdb_64.c b/arch/sparc/kernel/kgdb_64.c
index f5a0fd4..9bf387b 100644
--- a/arch/sparc/kernel/kgdb_64.c
+++ b/arch/sparc/kernel/kgdb_64.c
@@ -180,6 +180,12 @@ void kgdb_arch_exit(void)
{
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->tpc = ip;
+ regs->tnpc = regs->tpc + 4;
+}
+
struct kgdb_arch arch_kgdb_ops = {
/* Breakpoint instruction: ta 0x72 */
.gdb_bpt_instr = { 0x91, 0xd0, 0x20, 0x72 },
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 07/40] kgdb,sh: update superh kgdb exception handling
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (5 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 06/40] kgdb,sparc: Add in kgdb_arch_set_pc for sparc Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 08/40] kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin Jason Wessel
` (33 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Implement kgdb_arch_pc() which adjusts the pc if it needs to be
adjusted after a software breakpoint trap.
Implement kgdb_arch_set_pc() which is a new required function in the
kgdb debug core.
When processing a single step return zero in the error exception field
so that the debug core can distinguish between a single step trap and
a breakpoint trap generically.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
---
arch/sh/kernel/kgdb.c | 14 +++++++++++++-
1 files changed, 13 insertions(+), 1 deletions(-)
diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c
index 3e532d0..1ec03c9 100644
--- a/arch/sh/kernel/kgdb.c
+++ b/arch/sh/kernel/kgdb.c
@@ -237,6 +237,18 @@ int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
return -1;
}
+unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs)
+{
+ if (exception == 60)
+ return instruction_pointer(regs) - 2;
+ return instruction_pointer(regs);
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->pc = ip;
+}
+
/*
* The primary entry points for the kgdb debug trap table entries.
*/
@@ -247,7 +259,7 @@ BUILD_TRAP_HANDLER(singlestep)
local_irq_save(flags);
regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
- kgdb_handle_exception(vec >> 2, SIGTRAP, 0, regs);
+ kgdb_handle_exception(0, SIGTRAP, 0, regs);
local_irq_restore(flags);
}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 08/40] kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (6 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 07/40] kgdb,sh: update superh kgdb exception handling Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 09/40] kdb: core for kgdb back end (1 of 2) Jason Wessel
` (32 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Mike Frysinger
The new debug core api requires all architectures that use to debug
core to implement a function to set the program counter.
CC: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Sonic Zhang <sonic.zhang@analog.com>
---
arch/blackfin/kernel/kgdb.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/arch/blackfin/kernel/kgdb.c b/arch/blackfin/kernel/kgdb.c
index 34c7c3e..8cb6204 100644
--- a/arch/blackfin/kernel/kgdb.c
+++ b/arch/blackfin/kernel/kgdb.c
@@ -439,6 +439,11 @@ int kgdb_validate_break_address(unsigned long addr)
return -EFAULT;
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->retx = ip;
+}
+
int kgdb_arch_init(void)
{
kgdb_single_step = 0;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 09/40] kdb: core for kgdb back end (1 of 2)
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (7 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 08/40] kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 10/40] kdb: core for kgdb back end (2 " Jason Wessel
` (31 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, mort, linux-arch
This patch contains only the kdb core. Because the change set was
large, it was split. The next patch in the series includes the
instrumentation into the core kernel which are mainly helper functions
for kdb.
This work is directly derived from kdb v4.4 found at:
ftp://oss.sgi.com/projects/kdb/download/v4.4/
The kdb internals have been re-organized to make them mostly platform
independent and to connect everything to the debug core which is used by
gdbstub (which has long been known as kgdb).
The original version of kdb was 58,000 lines worth of changes to
support x86. From that implementation only the kdb shell, and basic
commands for memory access, runcontrol, lsmod, and dmesg where carried
forward.
This is a generic implementation which aims to cover all the current
architectures using the kgdb core: ppc, arm, x86, mips, sparc, sh and
blackfin. More archictectures can be added by implementing the
architecture specific kgdb functions.
[mort@sgi.com: Compile fix with hugepages enabled]
[mort@sgi.com: Clean breakpoint code renaming kdba_ -> kdb_]
[mort@sgi.com: fix new line after printing registers]
[mort@sgi.com: Remove the concept of global vs. local breakpoints]
[mort@sgi.com: Rework kdb_si_swapinfo to use more generic name]
CC: mort@sgi.com
CC: linux-arch@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
include/linux/kdb.h | 113 ++
kernel/debug/Makefile | 4 +-
kernel/debug/kdb/.gitignore | 1 +
kernel/debug/kdb/Makefile | 24 +
kernel/debug/kdb/kdb_bp.c | 567 ++++++++
kernel/debug/kdb/kdb_bt.c | 215 +++
kernel/debug/kdb/kdb_cmds | 32 +
kernel/debug/kdb/kdb_debugger.c | 157 +++
kernel/debug/kdb/kdb_io.c | 788 +++++++++++
kernel/debug/kdb/kdb_main.c | 2850 +++++++++++++++++++++++++++++++++++++++
kernel/debug/kdb/kdb_private.h | 400 ++++++
kernel/debug/kdb/kdb_support.c | 1007 ++++++++++++++
12 files changed, 6157 insertions(+), 1 deletions(-)
create mode 100644 include/linux/kdb.h
create mode 100644 kernel/debug/kdb/.gitignore
create mode 100644 kernel/debug/kdb/Makefile
create mode 100644 kernel/debug/kdb/kdb_bp.c
create mode 100644 kernel/debug/kdb/kdb_bt.c
create mode 100644 kernel/debug/kdb/kdb_cmds
create mode 100644 kernel/debug/kdb/kdb_debugger.c
create mode 100644 kernel/debug/kdb/kdb_io.c
create mode 100644 kernel/debug/kdb/kdb_main.c
create mode 100644 kernel/debug/kdb/kdb_private.h
create mode 100644 kernel/debug/kdb/kdb_support.c
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
new file mode 100644
index 0000000..d7fc145
--- /dev/null
+++ b/include/linux/kdb.h
@@ -0,0 +1,113 @@
+#ifndef _KDB_H
+#define _KDB_H
+
+/*
+ * Kernel Debugger Architecture Independent Global Headers
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2000-2007 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
+ * Copyright (C) 2009 Jason Wessel <jason.wessel@windriver.com>
+ */
+
+#ifdef CONFIG_KGDB_KDB
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <asm/atomic.h>
+
+#define KDB_POLL_FUNC_MAX 5
+
+/*
+ * kdb_initial_cpu is initialized to -1, and is set to the cpu
+ * number whenever the kernel debugger is entered.
+ */
+extern int kdb_initial_cpu;
+extern atomic_t kdb_event;
+
+#define KDB_IS_RUNNING() (kdb_initial_cpu != -1)
+
+/*
+ * kdb_diemsg
+ *
+ * Contains a pointer to the last string supplied to the
+ * kernel 'die' panic function.
+ */
+extern const char *kdb_diemsg;
+
+#define KDB_FLAG_EARLYKDB (1 << 0) /* set from boot parameter kdb=early */
+#define KDB_FLAG_CATASTROPHIC (1 << 1) /* A catastrophic event has occurred */
+#define KDB_FLAG_CMD_INTERRUPT (1 << 2) /* Previous command was interrupted */
+#define KDB_FLAG_NOIPI (1 << 3) /* Do not send IPIs */
+#define KDB_FLAG_ONLY_DO_DUMP (1 << 4) /* Only do a dump, used when
+ * kdb is off */
+#define KDB_FLAG_NO_CONSOLE (1 << 5) /* No console is available,
+ * kdb is disabled */
+#define KDB_FLAG_NO_VT_CONSOLE (1 << 6) /* No VT console is available, do
+ * not use keyboard */
+#define KDB_FLAG_NO_I8042 (1 << 7) /* No i8042 chip is available, do
+ * not use keyboard */
+
+extern int kdb_flags; /* Global flags, see kdb_state for per cpu state */
+
+extern void kdb_save_flags(void);
+extern void kdb_restore_flags(void);
+
+#define KDB_FLAG(flag) (kdb_flags & KDB_FLAG_##flag)
+#define KDB_FLAG_SET(flag) ((void)(kdb_flags |= KDB_FLAG_##flag))
+#define KDB_FLAG_CLEAR(flag) ((void)(kdb_flags &= ~KDB_FLAG_##flag))
+
+/*
+ * External entry point for the kernel debugger. The pt_regs
+ * at the time of entry are supplied along with the reason for
+ * entry to the kernel debugger.
+ */
+
+typedef enum {
+ KDB_REASON_ENTER = 1, /* KDB_ENTER() trap/fault - regs valid */
+ KDB_REASON_ENTER_SLAVE, /* KDB_ENTER_SLAVE() trap/fault - regs valid */
+ KDB_REASON_BREAK, /* Breakpoint inst. - regs valid */
+ KDB_REASON_DEBUG, /* Debug Fault - regs valid */
+ KDB_REASON_OOPS, /* Kernel Oops - regs valid */
+ KDB_REASON_SWITCH, /* CPU switch - regs valid*/
+ KDB_REASON_KEYBOARD, /* Keyboard entry - regs valid */
+ KDB_REASON_NMI, /* Non-maskable interrupt; regs valid */
+ KDB_REASON_RECURSE, /* Recursive entry to kdb;
+ * regs probably valid */
+ KDB_REASON_SSTEP, /* Single Step trap. - regs valid */
+} kdb_reason_t;
+
+extern int kdb_printf(const char *, ...)
+ __attribute__ ((format (printf, 1, 2)));
+typedef int (*kdb_printf_t)(const char *, ...)
+ __attribute__ ((format (printf, 1, 2)));
+extern void kdb_init(void);
+
+/* Access to kdb specific polling devices */
+typedef int (*get_char_func)(void);
+extern get_char_func kdb_poll_funcs[];
+extern int kdb_get_kbd_char(void);
+
+static inline
+int kdb_process_cpu(const struct task_struct *p)
+{
+ unsigned int cpu = task_thread_info(p)->cpu;
+ if (cpu > num_possible_cpus())
+ cpu = 0;
+ return cpu;
+}
+
+/* kdb access functions for non-kdb files*/
+#ifdef CONFIG_SWAP
+extern void kdb_si_swapinfo(struct sysinfo *);
+#else
+#include <linux/swap.h>
+#define kdb_si_swapinfo(x) si_swapinfo(x)
+#endif
+
+#else /* ! CONFIG_KGDB_KDB */
+#define KDB_IS_RUNNING() (0)
+#endif /* CONFIG_KGDB_KDB */
+#endif /* !_KDB_H */
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile
index 3657c64..c72de00 100644
--- a/kernel/debug/Makefile
+++ b/kernel/debug/Makefile
@@ -2,4 +2,6 @@
# Makefile for the linux kernel debugger
#
-obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o
\ No newline at end of file
+obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o
+obj-$(CONFIG_KGDB_KDB) += kdb/
+
diff --git a/kernel/debug/kdb/.gitignore b/kernel/debug/kdb/.gitignore
new file mode 100644
index 0000000..396d12e
--- /dev/null
+++ b/kernel/debug/kdb/.gitignore
@@ -0,0 +1 @@
+gen-kdb_cmds.c
diff --git a/kernel/debug/kdb/Makefile b/kernel/debug/kdb/Makefile
new file mode 100644
index 0000000..93f9e64
--- /dev/null
+++ b/kernel/debug/kdb/Makefile
@@ -0,0 +1,24 @@
+# This file is subject to the terms and conditions of the GNU General Public
+# License. See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (c) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
+# Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+#
+
+CCVERSION := $(shell $(CC) -v 2>&1 | sed -ne '$$p')
+obj-y := kdb_io.o kdb_main.o kdb_support.o kdb_bt.o gen-kdb_cmds.o kdb_bp.o kdb_debugger.o
+
+clean-files := gen-kdb_cmds.c
+
+quiet_cmd_gen-kdb = GENKDB $@
+ cmd_gen-kdb = $(AWK) 'BEGIN {print "\#include <linux/stddef.h>"; print "\#include <linux/init.h>"} \
+ /^\#/{next} \
+ /^[ \t]*$$/{next} \
+ {gsub(/"/, "\\\"", $$0); \
+ print "static __initdata char kdb_cmd" cmds++ "[] = \"" $$0 "\\n\";"} \
+ END {print "extern char *kdb_cmds[]; char __initdata *kdb_cmds[] = {"; for (i = 0; i < cmds; ++i) {print " kdb_cmd" i ","}; print(" NULL\n};");}' \
+ $(filter-out %/Makefile,$^) > $@#
+
+$(obj)/gen-kdb_cmds.c: $(src)/kdb_cmds $(if $(KDB_CMDS),(wildcard $(TOPDIR)/arch/$(KDB_CMDS))) $(src)/Makefile
+ $(call cmd,gen-kdb)
diff --git a/kernel/debug/kdb/kdb_bp.c b/kernel/debug/kdb/kdb_bp.c
new file mode 100644
index 0000000..2e3b146
--- /dev/null
+++ b/kernel/debug/kdb/kdb_bp.c
@@ -0,0 +1,567 @@
+/*
+ * Kernel Debugger Architecture Independent Breakpoint Handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/kdb.h>
+#include <linux/kgdb.h>
+#include <linux/smp.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include "kdb_private.h"
+
+/*
+ * Table of kdb_breakpoints
+ */
+kdb_bp_t kdb_breakpoints[KDB_MAXBPT];
+
+static void kdb_setsinglestep(struct pt_regs *regs)
+{
+ KDB_STATE_SET(DOING_SS);
+}
+
+static char *kdb_rwtypes[] = {
+ "Instruction(i)",
+ "Instruction(Register)",
+ "Data Write",
+ "I/O",
+ "Data Access"
+};
+
+static char *kdb_bptype(kdb_bp_t *bp)
+{
+ if (bp->bp_type < 0 || bp->bp_type > 4)
+ return "";
+
+ return kdb_rwtypes[bp->bp_type];
+}
+
+static int kdb_parsebp(int argc, const char **argv, int *nextargp, kdb_bp_t *bp)
+{
+ int nextarg = *nextargp;
+ int diag;
+
+ bp->bph_length = 1;
+ if ((argc + 1) != nextarg) {
+ if (strnicmp(argv[nextarg], "datar", sizeof("datar")) == 0)
+ bp->bp_type = BP_ACCESS_WATCHPOINT;
+ else if (strnicmp(argv[nextarg], "dataw", sizeof("dataw")) == 0)
+ bp->bp_type = BP_WRITE_WATCHPOINT;
+ else if (strnicmp(argv[nextarg], "inst", sizeof("inst")) == 0)
+ bp->bp_type = BP_HARDWARE_BREAKPOINT;
+ else
+ return KDB_ARGCOUNT;
+
+ bp->bph_length = 1;
+
+ nextarg++;
+
+ if ((argc + 1) != nextarg) {
+ unsigned long len;
+
+ diag = kdbgetularg((char *)argv[nextarg],
+ &len);
+ if (diag)
+ return diag;
+
+
+ if (len > 8)
+ return KDB_BADLENGTH;
+
+ bp->bph_length = len;
+ nextarg++;
+ }
+
+ if ((argc + 1) != nextarg)
+ return KDB_ARGCOUNT;
+ }
+
+ *nextargp = nextarg;
+ return 0;
+}
+
+static int _kdb_bp_remove(kdb_bp_t *bp)
+{
+ int ret = 1;
+ if (!bp->bp_installed)
+ return ret;
+ if (!bp->bp_type)
+ ret = dbg_remove_sw_break(bp->bp_addr);
+ else
+ ret = arch_kgdb_ops.remove_hw_breakpoint(bp->bp_addr,
+ bp->bph_length,
+ bp->bp_type);
+ if (ret == 0)
+ bp->bp_installed = 0;
+ return ret;
+}
+
+static void kdb_handle_bp(struct pt_regs *regs, kdb_bp_t *bp)
+{
+ if (KDB_NULL_REGS(regs))
+ return;
+
+ if (KDB_DEBUG(BP))
+ kdb_printf("regs->ip = 0x%lx\n", instruction_pointer(regs));
+
+ /*
+ * Setup single step
+ */
+ kdb_setsinglestep(regs);
+
+ /*
+ * Reset delay attribute
+ */
+ bp->bp_delay = 0;
+ bp->bp_delayed = 1;
+}
+
+static int _kdb_bp_install(struct pt_regs *regs, kdb_bp_t *bp)
+{
+ int ret;
+ /*
+ * Install the breakpoint, if it is not already installed.
+ */
+
+ if (KDB_DEBUG(BP))
+ kdb_printf("%s: bp_installed %d\n",
+ __func__, bp->bp_installed);
+ if (!KDB_STATE(SSBPT))
+ bp->bp_delay = 0;
+ if (bp->bp_installed)
+ return 1;
+ if (bp->bp_delay || (bp->bp_delayed && KDB_STATE(DOING_SS))) {
+ if (KDB_DEBUG(BP))
+ kdb_printf("%s: delayed bp\n", __func__);
+ kdb_handle_bp(regs, bp);
+ return 0;
+ }
+ if (!bp->bp_type)
+ ret = dbg_set_sw_break(bp->bp_addr);
+ else
+ ret = arch_kgdb_ops.set_hw_breakpoint(bp->bp_addr,
+ bp->bph_length,
+ bp->bp_type);
+ if (ret == 0) {
+ bp->bp_installed = 1;
+ } else {
+ kdb_printf("%s: failed to set breakpoint at 0x%lx\n",
+ __func__, bp->bp_addr);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * kdb_bp_install
+ *
+ * Install kdb_breakpoints prior to returning from the
+ * kernel debugger. This allows the kdb_breakpoints to be set
+ * upon functions that are used internally by kdb, such as
+ * printk(). This function is only called once per kdb session.
+ */
+void kdb_bp_install(struct pt_regs *regs)
+{
+ int i;
+
+ for (i = 0; i < KDB_MAXBPT; i++) {
+ kdb_bp_t *bp = &kdb_breakpoints[i];
+
+ if (KDB_DEBUG(BP)) {
+ kdb_printf("%s: bp %d bp_enabled %d\n",
+ __func__, i, bp->bp_enabled);
+ }
+ if (bp->bp_enabled)
+ _kdb_bp_install(regs, bp);
+ }
+}
+
+/*
+ * kdb_bp_remove
+ *
+ * Remove kdb_breakpoints upon entry to the kernel debugger.
+ *
+ * Parameters:
+ * None.
+ * Outputs:
+ * None.
+ * Returns:
+ * None.
+ * Locking:
+ * None.
+ * Remarks:
+ */
+void kdb_bp_remove(void)
+{
+ int i;
+
+ for (i = KDB_MAXBPT - 1; i >= 0; i--) {
+ kdb_bp_t *bp = &kdb_breakpoints[i];
+
+ if (KDB_DEBUG(BP)) {
+ kdb_printf("%s: bp %d bp_enabled %d\n",
+ __func__, i, bp->bp_enabled);
+ }
+ if (bp->bp_enabled)
+ _kdb_bp_remove(bp);
+ }
+}
+
+
+/*
+ * kdb_printbp
+ *
+ * Internal function to format and print a breakpoint entry.
+ *
+ * Parameters:
+ * None.
+ * Outputs:
+ * None.
+ * Returns:
+ * None.
+ * Locking:
+ * None.
+ * Remarks:
+ */
+
+static void kdb_printbp(kdb_bp_t *bp, int i)
+{
+ kdb_printf("%s ", kdb_bptype(bp));
+ kdb_printf("BP #%d at ", i);
+ kdb_symbol_print(bp->bp_addr, NULL, KDB_SP_DEFAULT);
+
+ if (bp->bp_enabled)
+ kdb_printf("\n is enabled");
+ else
+ kdb_printf("\n is disabled");
+
+ kdb_printf("\taddr at %016lx, hardtype=%d installed=%d\n",
+ bp->bp_addr, bp->bp_type, bp->bp_installed);
+
+ kdb_printf("\n");
+}
+
+/*
+ * kdb_bp
+ *
+ * Handle the bp commands.
+ *
+ * [bp|bph] <addr-expression> [DATAR|DATAW]
+ *
+ * Parameters:
+ * argc Count of arguments in argv
+ * argv Space delimited command line arguments
+ * Outputs:
+ * None.
+ * Returns:
+ * Zero for success, a kdb diagnostic if failure.
+ * Locking:
+ * None.
+ * Remarks:
+ *
+ * bp Set breakpoint on all cpus. Only use hardware assist if need.
+ * bph Set breakpoint on all cpus. Force hardware register
+ */
+
+static int kdb_bp(int argc, const char **argv)
+{
+ int i, bpno;
+ kdb_bp_t *bp, *bp_check;
+ int diag;
+ int free;
+ char *symname = NULL;
+ long offset = 0ul;
+ int nextarg;
+ kdb_bp_t template = {0};
+
+ if (argc == 0) {
+ /*
+ * Display breakpoint table
+ */
+ for (bpno = 0, bp = kdb_breakpoints; bpno < KDB_MAXBPT;
+ bpno++, bp++) {
+ if (bp->bp_free)
+ continue;
+ kdb_printbp(bp, bpno);
+ }
+
+ return 0;
+ }
+
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &template.bp_addr,
+ &offset, &symname);
+ if (diag)
+ return diag;
+ if (!template.bp_addr)
+ return KDB_BADINT;
+
+ /*
+ * Find an empty bp structure to allocate
+ */
+ free = KDB_MAXBPT;
+ for (bpno = 0, bp = kdb_breakpoints; bpno < KDB_MAXBPT; bpno++, bp++) {
+ if (bp->bp_free)
+ break;
+ }
+
+ if (bpno == KDB_MAXBPT)
+ return KDB_TOOMANYBPT;
+
+ if (strcmp(argv[0], "bph") == 0) {
+ template.bp_type = BP_HARDWARE_BREAKPOINT;
+ diag = kdb_parsebp(argc, argv, &nextarg, &template);
+ if (diag)
+ return diag;
+ } else {
+ template.bp_type = BP_BREAKPOINT;
+ }
+
+ /*
+ * Check for clashing breakpoints.
+ *
+ * Note, in this design we can't have hardware breakpoints
+ * enabled for both read and write on the same address.
+ */
+ for (i = 0, bp_check = kdb_breakpoints; i < KDB_MAXBPT;
+ i++, bp_check++) {
+ if (!bp_check->bp_free &&
+ bp_check->bp_addr == template.bp_addr) {
+ kdb_printf("You already have a breakpoint at "
+ kdb_bfd_vma_fmt0 "\n", template.bp_addr);
+ return KDB_DUPBPT;
+ }
+ }
+
+ template.bp_enabled = 1;
+
+ /*
+ * Actually allocate the breakpoint found earlier
+ */
+ *bp = template;
+ bp->bp_free = 0;
+
+ kdb_printbp(bp, bpno);
+
+ return 0;
+}
+
+/*
+ * kdb_bc
+ *
+ * Handles the 'bc', 'be', and 'bd' commands
+ *
+ * [bd|bc|be] <breakpoint-number>
+ * [bd|bc|be] *
+ *
+ * Parameters:
+ * argc Count of arguments in argv
+ * argv Space delimited command line arguments
+ * Outputs:
+ * None.
+ * Returns:
+ * Zero for success, a kdb diagnostic for failure
+ * Locking:
+ * None.
+ * Remarks:
+ */
+static int kdb_bc(int argc, const char **argv)
+{
+ unsigned long addr;
+ kdb_bp_t *bp = NULL;
+ int lowbp = KDB_MAXBPT;
+ int highbp = 0;
+ int done = 0;
+ int i;
+ int diag = 0;
+
+ int cmd; /* KDBCMD_B? */
+#define KDBCMD_BC 0
+#define KDBCMD_BE 1
+#define KDBCMD_BD 2
+
+ if (strcmp(argv[0], "be") == 0)
+ cmd = KDBCMD_BE;
+ else if (strcmp(argv[0], "bd") == 0)
+ cmd = KDBCMD_BD;
+ else
+ cmd = KDBCMD_BC;
+
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+
+ if (strcmp(argv[1], "*") == 0) {
+ lowbp = 0;
+ highbp = KDB_MAXBPT;
+ } else {
+ diag = kdbgetularg(argv[1], &addr);
+ if (diag)
+ return diag;
+
+ /*
+ * For addresses less than the maximum breakpoint number,
+ * assume that the breakpoint number is desired.
+ */
+ if (addr < KDB_MAXBPT) {
+ bp = &kdb_breakpoints[addr];
+ lowbp = highbp = addr;
+ highbp++;
+ } else {
+ for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT;
+ i++, bp++) {
+ if (bp->bp_addr == addr) {
+ lowbp = highbp = i;
+ highbp++;
+ break;
+ }
+ }
+ }
+ }
+
+ /*
+ * Now operate on the set of breakpoints matching the input
+ * criteria (either '*' for all, or an individual breakpoint).
+ */
+ for (bp = &kdb_breakpoints[lowbp], i = lowbp;
+ i < highbp;
+ i++, bp++) {
+ if (bp->bp_free)
+ continue;
+
+ done++;
+
+ switch (cmd) {
+ case KDBCMD_BC:
+ bp->bp_enabled = 0;
+
+ kdb_printf("Breakpoint %d at "
+ kdb_bfd_vma_fmt " cleared\n",
+ i, bp->bp_addr);
+
+ bp->bp_addr = 0;
+ bp->bp_free = 1;
+
+ break;
+ case KDBCMD_BE:
+ bp->bp_enabled = 1;
+
+ kdb_printf("Breakpoint %d at "
+ kdb_bfd_vma_fmt " enabled",
+ i, bp->bp_addr);
+
+ kdb_printf("\n");
+ break;
+ case KDBCMD_BD:
+ if (!bp->bp_enabled)
+ break;
+
+ bp->bp_enabled = 0;
+
+ kdb_printf("Breakpoint %d at "
+ kdb_bfd_vma_fmt " disabled\n",
+ i, bp->bp_addr);
+
+ break;
+ }
+ if (bp->bp_delay && (cmd == KDBCMD_BC || cmd == KDBCMD_BD)) {
+ bp->bp_delay = 0;
+ KDB_STATE_CLEAR(SSBPT);
+ }
+ }
+
+ return (!done) ? KDB_BPTNOTFOUND : 0;
+}
+
+/*
+ * kdb_ss
+ *
+ * Process the 'ss' (Single Step) and 'ssb' (Single Step to Branch)
+ * commands.
+ *
+ * ss
+ * ssb
+ *
+ * Parameters:
+ * argc Argument count
+ * argv Argument vector
+ * Outputs:
+ * None.
+ * Returns:
+ * KDB_CMD_SS[B] for success, a kdb error if failure.
+ * Locking:
+ * None.
+ * Remarks:
+ *
+ * Set the arch specific option to trigger a debug trap after the next
+ * instruction.
+ *
+ * For 'ssb', set the trace flag in the debug trap handler
+ * after printing the current insn and return directly without
+ * invoking the kdb command processor, until a branch instruction
+ * is encountered.
+ */
+
+static int kdb_ss(int argc, const char **argv)
+{
+ int ssb = 0;
+
+ ssb = (strcmp(argv[0], "ssb") == 0);
+ if (argc != 0)
+ return KDB_ARGCOUNT;
+ /*
+ * Set trace flag and go.
+ */
+ KDB_STATE_SET(DOING_SS);
+ if (ssb) {
+ KDB_STATE_SET(DOING_SSB);
+ return KDB_CMD_SSB;
+ }
+ return KDB_CMD_SS;
+}
+
+/* Initialize the breakpoint table and register breakpoint commands. */
+
+void __init kdb_initbptab(void)
+{
+ int i;
+ kdb_bp_t *bp;
+
+ /*
+ * First time initialization.
+ */
+ memset(&kdb_breakpoints, '\0', sizeof(kdb_breakpoints));
+
+ for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++)
+ bp->bp_free = 1;
+
+ kdb_register_repeat("bp", kdb_bp, "[<vaddr>]",
+ "Set/Display breakpoints", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("bl", kdb_bp, "[<vaddr>]",
+ "Display breakpoints", 0, KDB_REPEAT_NO_ARGS);
+ if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT)
+ kdb_register_repeat("bph", kdb_bp, "[<vaddr>]",
+ "[datar [length]|dataw [length]] Set hw brk", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("bc", kdb_bc, "<bpnum>",
+ "Clear Breakpoint", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("be", kdb_bc, "<bpnum>",
+ "Enable Breakpoint", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("bd", kdb_bc, "<bpnum>",
+ "Disable Breakpoint", 0, KDB_REPEAT_NONE);
+
+ kdb_register_repeat("ss", kdb_ss, "",
+ "Single Step", 1, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("ssb", kdb_ss, "",
+ "Single step to branch/call", 0, KDB_REPEAT_NO_ARGS);
+ /*
+ * Architecture dependent initialization.
+ */
+}
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c
new file mode 100644
index 0000000..c73402c
--- /dev/null
+++ b/kernel/debug/kdb/kdb_bt.c
@@ -0,0 +1,215 @@
+/*
+ * Kernel Debugger Architecture Independent Stack Traceback
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/kdb.h>
+#include <linux/nmi.h>
+#include <asm/system.h>
+#include "kdb_private.h"
+
+
+static void kdb_show_stack(struct task_struct *p, void *addr)
+{
+ int old_lvl = console_loglevel;
+ console_loglevel = 15;
+ kdb_set_current_task(p);
+ if (addr) {
+ show_stack((struct task_struct *)p, addr);
+ } else if (kdb_current_regs) {
+#ifdef CONFIG_X86
+ show_stack(p, &kdb_current_regs->sp);
+#else
+ show_stack(p, NULL);
+#endif
+ } else {
+ show_stack(p, NULL);
+ }
+ console_loglevel = old_lvl;
+}
+
+/*
+ * kdb_bt
+ *
+ * This function implements the 'bt' command. Print a stack
+ * traceback.
+ *
+ * bt [<address-expression>] (addr-exp is for alternate stacks)
+ * btp <pid> Kernel stack for <pid>
+ * btt <address-expression> Kernel stack for task structure at
+ * <address-expression>
+ * bta [DRSTCZEUIMA] All useful processes, optionally
+ * filtered by state
+ * btc [<cpu>] The current process on one cpu,
+ * default is all cpus
+ *
+ * bt <address-expression> refers to a address on the stack, that location
+ * is assumed to contain a return address.
+ *
+ * btt <address-expression> refers to the address of a struct task.
+ *
+ * Inputs:
+ * argc argument count
+ * argv argument vector
+ * Outputs:
+ * None.
+ * Returns:
+ * zero for success, a kdb diagnostic if error
+ * Locking:
+ * none.
+ * Remarks:
+ * Backtrack works best when the code uses frame pointers. But even
+ * without frame pointers we should get a reasonable trace.
+ *
+ * mds comes in handy when examining the stack to do a manual traceback or
+ * to get a starting point for bt <address-expression>.
+ */
+
+static int
+kdb_bt1(struct task_struct *p, unsigned long mask,
+ int argcount, int btaprompt)
+{
+ char buffer[2];
+ if (kdb_getarea(buffer[0], (unsigned long)p) ||
+ kdb_getarea(buffer[0], (unsigned long)(p+1)-1))
+ return KDB_BADADDR;
+ if (!kdb_task_state(p, mask))
+ return 0;
+ kdb_printf("Stack traceback for pid %d\n", p->pid);
+ kdb_ps1(p);
+ kdb_show_stack(p, NULL);
+ if (btaprompt) {
+ kdb_getstr(buffer, sizeof(buffer),
+ "Enter <q> to end, <cr> to continue:");
+ if (buffer[0] == 'q') {
+ kdb_printf("\n");
+ return 1;
+ }
+ }
+ touch_nmi_watchdog();
+ return 0;
+}
+
+int
+kdb_bt(int argc, const char **argv)
+{
+ int diag;
+ int argcount = 5;
+ int btaprompt = 1;
+ int nextarg;
+ unsigned long addr;
+ long offset;
+
+ kdbgetintenv("BTARGS", &argcount); /* Arguments to print */
+ kdbgetintenv("BTAPROMPT", &btaprompt); /* Prompt after each
+ * proc in bta */
+
+ if (strcmp(argv[0], "bta") == 0) {
+ struct task_struct *g, *p;
+ unsigned long cpu;
+ unsigned long mask = kdb_task_state_string(argc ? argv[1] :
+ NULL);
+ if (argc == 0)
+ kdb_ps_suppressed();
+ /* Run the active tasks first */
+ for_each_online_cpu(cpu) {
+ p = kdb_curr_task(cpu);
+ if (kdb_bt1(p, mask, argcount, btaprompt))
+ return 0;
+ }
+ /* Now the inactive tasks */
+ kdb_do_each_thread(g, p) {
+ if (task_curr(p))
+ continue;
+ if (kdb_bt1(p, mask, argcount, btaprompt))
+ return 0;
+ } kdb_while_each_thread(g, p);
+ } else if (strcmp(argv[0], "btp") == 0) {
+ struct task_struct *p;
+ unsigned long pid;
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+ diag = kdbgetularg((char *)argv[1], &pid);
+ if (diag)
+ return diag;
+ p = find_task_by_pid_ns(pid, &init_pid_ns);
+ if (p) {
+ kdb_set_current_task(p);
+ return kdb_bt1(p, ~0UL, argcount, 0);
+ }
+ kdb_printf("No process with pid == %ld found\n", pid);
+ return 0;
+ } else if (strcmp(argv[0], "btt") == 0) {
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+ diag = kdbgetularg((char *)argv[1], &addr);
+ if (diag)
+ return diag;
+ kdb_set_current_task((struct task_struct *)addr);
+ return kdb_bt1((struct task_struct *)addr, ~0UL, argcount, 0);
+ } else if (strcmp(argv[0], "btc") == 0) {
+ unsigned long cpu = ~0;
+ struct kdb_running_process *krp;
+ struct task_struct *save_current_task = kdb_current_task;
+ char buf[80];
+ if (argc > 1)
+ return KDB_ARGCOUNT;
+ if (argc == 1) {
+ diag = kdbgetularg((char *)argv[1], &cpu);
+ if (diag)
+ return diag;
+ }
+ /* Recursive use of kdb_parse, do not use argv after
+ * this point */
+ argv = NULL;
+ if (cpu != ~0) {
+ krp = kdb_running_process + cpu;
+ if (cpu >= num_possible_cpus() || !krp->seqno ||
+ !cpu_online(cpu)) {
+ kdb_printf("no process for cpu %ld\n", cpu);
+ return 0;
+ }
+ sprintf(buf, "btt 0x%p\n", krp->p);
+ kdb_parse(buf);
+ return 0;
+ }
+ kdb_printf("btc: cpu status: ");
+ kdb_parse("cpu\n");
+ for (cpu = 0, krp = kdb_running_process;
+ cpu < num_possible_cpus();
+ cpu++, krp++) {
+ if (!cpu_online(cpu) || !krp->seqno)
+ continue;
+ sprintf(buf, "btt 0x%p\n", krp->p);
+ kdb_parse(buf);
+ touch_nmi_watchdog();
+ }
+ kdb_set_current_task(save_current_task);
+ return 0;
+ } else {
+ if (argc) {
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
+ &offset, NULL);
+ if (diag)
+ return diag;
+ kdb_show_stack(kdb_current_task, (void *)addr);
+ return 0;
+ } else {
+ return kdb_bt1(kdb_current_task, ~0UL, argcount, 0);
+ }
+ }
+
+ /* NOTREACHED */
+ return 0;
+}
diff --git a/kernel/debug/kdb/kdb_cmds b/kernel/debug/kdb/kdb_cmds
new file mode 100644
index 0000000..343955c
--- /dev/null
+++ b/kernel/debug/kdb/kdb_cmds
@@ -0,0 +1,32 @@
+# Initial commands for kdb, alter to suit your needs.
+# These commands are executed in kdb_init() context, no SMP, no
+# processes. Commands that require process data (including stack or
+# registers) are not reliable this early. set and bp commands should
+# be safe. Global breakpoint commands affect each cpu as it is booted.
+
+# Standard debugging information for first level support, just type archkdb
+# or archkdbcpu or archkdbshort at the kdb prompt.
+
+defcmd archkdb "" "First line arch debugging"
+ set BTSYMARG 1
+ set BTARGS 9
+ pid R
+ -archkdbcommon
+ -bta
+endefcmd
+
+defcmd archkdbcpu "" "archkdb with only tasks on cpus"
+ set BTSYMARG 1
+ set BTARGS 9
+ pid R
+ -archkdbcommon
+ -btc
+endefcmd
+
+defcmd archkdbshort "" "archkdb with less detailed backtrace"
+ set BTSYMARG 0
+ set BTARGS 0
+ pid R
+ -archkdbcommon
+ -bta
+endefcmd
diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
new file mode 100644
index 0000000..4cc5a69
--- /dev/null
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -0,0 +1,157 @@
+/*
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/kdebug.h>
+#include "kdb_private.h"
+#include "../debug_core.h"
+
+/*
+ * KDB interface to KGDB internals
+ */
+get_char_func kdb_poll_funcs[] = {
+ dbg_io_get_char,
+ NULL,
+};
+
+int kdb_stub(struct kgdb_state *ks)
+{
+ int error = 0;
+ kdb_bp_t *bp;
+ unsigned long addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
+ kdb_reason_t reason = KDB_REASON_OOPS;
+ kdb_dbtrap_t db_result = KDB_DB_NOBPT;
+ int i;
+
+ if (KDB_STATE(REENTRY)) {
+ reason = KDB_REASON_SWITCH;
+ KDB_STATE_CLEAR(REENTRY);
+ addr = instruction_pointer(ks->linux_regs);
+ }
+ ks->pass_exception = 0;
+ if (atomic_read(&kgdb_setting_breakpoint))
+ reason = KDB_REASON_KEYBOARD;
+
+ for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
+ if ((bp->bp_enabled) && (bp->bp_addr == addr)) {
+ reason = KDB_REASON_BREAK;
+ db_result = KDB_DB_BPT;
+ if (addr != instruction_pointer(ks->linux_regs))
+ kgdb_arch_set_pc(ks->linux_regs, addr);
+ break;
+ }
+ }
+ if (reason == KDB_REASON_BREAK || reason == KDB_REASON_SWITCH) {
+ for (i = 0, bp = kdb_breakpoints; i < KDB_MAXBPT; i++, bp++) {
+ if (bp->bp_free)
+ continue;
+ if (bp->bp_addr == addr) {
+ bp->bp_delay = 1;
+ bp->bp_delayed = 1;
+ /* SSBPT is set when the kernel debugger must
+ * single step a task in order to re-establish
+ * an instruction breakpoint which uses the
+ * instruction replacement mechanism. It is
+ * cleared by any action that removes the need
+ * to single-step the breakpoint.
+ */
+ reason = KDB_REASON_BREAK;
+ db_result = KDB_DB_BPT;
+ KDB_STATE_SET(SSBPT);
+ break;
+ }
+ }
+ }
+
+ if (reason != KDB_REASON_BREAK && ks->ex_vector == 0 &&
+ ks->signo == SIGTRAP) {
+ reason = KDB_REASON_SSTEP;
+ db_result = KDB_DB_BPT;
+ }
+ /* Set initial kdb state variables */
+ KDB_STATE_CLEAR(KGDB_TRANS);
+ kdb_initial_cpu = ks->cpu;
+ kdb_current_task = kgdb_info[ks->cpu].task;
+ kdb_current_regs = kgdb_info[ks->cpu].debuggerinfo;
+ /* Remove any breakpoints as needed by kdb and clear single step*/
+ kdb_bp_remove();
+ KDB_STATE_CLEAR(DOING_SS);
+ KDB_STATE_CLEAR(DOING_SSB);
+ for_each_online_cpu(i) {
+ kdb_save_running_cpu(kgdb_info[i].debuggerinfo,
+ kgdb_info[i].task, i);
+ }
+ if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) {
+ ks->pass_exception = 1;
+ KDB_FLAG_SET(CATASTROPHIC);
+ }
+ kdb_initial_cpu = ks->cpu;
+ if (KDB_STATE(SSBPT) && reason == KDB_REASON_SSTEP) {
+ KDB_STATE_CLEAR(SSBPT);
+ KDB_STATE_CLEAR(DOING_SS);
+ } else {
+ /* Start kdb main loop */
+ error = kdb_main_loop(KDB_REASON_ENTER, reason,
+ ks->err_code, db_result, ks->linux_regs);
+ }
+ /* Upon exit from the kdb main loop setup break points and restart
+ * the system based on the requested continue state
+ */
+ kdb_initial_cpu = -1;
+ kdb_current_task = NULL;
+ kdb_current_regs = NULL;
+ kdbnearsym_cleanup();
+ if (error == KDB_CMD_KGDB) {
+ if (KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)) {
+ /* This inteface glue which allows kdb to
+ * transition in into the gdb stub. In order
+ * to do this the '?' gdb serial packet
+ * response is processed here. Or the empty
+ * packet response is sent to the connected
+ * debugger to complete the initial gdb
+ * handshake.
+ */
+ if (KDB_STATE(DOING_KGDB))
+ gdbstub_state(ks, "?");
+ else
+ gdbstub_state(ks, "");
+ KDB_STATE_CLEAR(DOING_KGDB);
+ KDB_STATE_CLEAR(DOING_KGDB2);
+ }
+ return DBG_PASS_EVENT;
+ }
+ kdb_bp_install(ks->linux_regs);
+ dbg_activate_sw_breakpoints();
+ /* Set the exit state to a single step or a continue */
+ if (KDB_STATE(DOING_SS))
+ gdbstub_state(ks, "s");
+ else
+ gdbstub_state(ks, "c");
+
+ KDB_FLAG_CLEAR(CATASTROPHIC);
+
+ /* Invoke any final arch specific exception handling before
+ * resuming the system
+ */
+ kgdb_info[ks->cpu].ret_state = gdbstub_state(ks, "e");
+ if (ks->pass_exception)
+ kgdb_info[ks->cpu].ret_state = 1;
+ if (error == KDB_CMD_CPU) {
+ KDB_STATE_SET_CPU(REENTRY, dbg_switch_cpu);
+ /* Force clear the single step bit because kdb emulates this
+ * differently vs the gdbstub */
+ kgdb_single_step = 0;
+ dbg_deactivate_sw_breakpoints();
+ return DBG_SWITCH_CPU_EVENT;
+ }
+ return kgdb_info[ks->cpu].ret_state;
+}
+
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
new file mode 100644
index 0000000..01fc16d
--- /dev/null
+++ b/kernel/debug/kdb/kdb_io.c
@@ -0,0 +1,788 @@
+/*
+ * Kernel Debugger Architecture Independent Console I/O handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2006 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/kdev_t.h>
+#include <linux/console.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/nmi.h>
+#include <linux/delay.h>
+#include <linux/kdb.h>
+#include <linux/kallsyms.h>
+#include "kdb_private.h"
+
+#define CMD_BUFLEN 256
+char kdb_prompt_str[CMD_BUFLEN];
+
+
+static void kgdb_transition_check(char *buffer)
+{
+ int slen = strlen(buffer);
+ if (strncmp(buffer, "$?#3f", slen) != 0 &&
+ strncmp(buffer, "$qSupported#37", slen) != 0 &&
+ strncmp(buffer, "+$qSupported#37", slen) != 0) {
+ KDB_STATE_SET(KGDB_TRANS);
+ kdb_printf("%s", buffer);
+ }
+}
+
+static int kdb_read_get_key(char *buffer, size_t bufsize)
+{
+#define ESCAPE_UDELAY 1000
+#define ESCAPE_DELAY (2*1000000/ESCAPE_UDELAY) /* 2 seconds worth of udelays */
+ char escape_data[5]; /* longest vt100 escape sequence is 4 bytes */
+ char *ped = escape_data;
+ int escape_delay = 0;
+ get_char_func *f, *f_escape = NULL;
+ int key;
+
+ for (f = &kdb_poll_funcs[0]; ; ++f) {
+ if (*f == NULL) {
+ /* Reset NMI watchdog once per poll loop */
+ touch_nmi_watchdog();
+ f = &kdb_poll_funcs[0];
+ }
+ if (escape_delay == 2) {
+ *ped = '\0';
+ ped = escape_data;
+ --escape_delay;
+ }
+ if (escape_delay == 1) {
+ key = *ped++;
+ if (!*ped)
+ --escape_delay;
+ break;
+ }
+ key = (*f)();
+ if (key == -1) {
+ if (escape_delay) {
+ udelay(ESCAPE_UDELAY);
+ --escape_delay;
+ }
+ continue;
+ }
+ if (bufsize <= 2) {
+ if (key == '\r')
+ key = '\n';
+ *buffer++ = key;
+ *buffer = '\0';
+ return -1;
+ }
+ if (escape_delay == 0 && key == '\e') {
+ escape_delay = ESCAPE_DELAY;
+ ped = escape_data;
+ f_escape = f;
+ }
+ if (escape_delay) {
+ *ped++ = key;
+ if (f_escape != f) {
+ escape_delay = 2;
+ continue;
+ }
+ if (ped - escape_data == 1) {
+ /* \e */
+ continue;
+ } else if (ped - escape_data == 2) {
+ /* \e<something> */
+ if (key != '[')
+ escape_delay = 2;
+ continue;
+ } else if (ped - escape_data == 3) {
+ /* \e[<something> */
+ int mapkey = 0;
+ switch (key) {
+ case 'A': /* \e[A, up arrow */
+ mapkey = 16;
+ break;
+ case 'B': /* \e[B, down arrow */
+ mapkey = 14;
+ break;
+ case 'C': /* \e[C, right arrow */
+ mapkey = 6;
+ break;
+ case 'D': /* \e[D, left arrow */
+ mapkey = 2;
+ break;
+ case '1': /* dropthrough */
+ case '3': /* dropthrough */
+ /* \e[<1,3,4>], may be home, del, end */
+ case '4':
+ mapkey = -1;
+ break;
+ }
+ if (mapkey != -1) {
+ if (mapkey > 0) {
+ escape_data[0] = mapkey;
+ escape_data[1] = '\0';
+ }
+ escape_delay = 2;
+ }
+ continue;
+ } else if (ped - escape_data == 4) {
+ /* \e[<1,3,4><something> */
+ int mapkey = 0;
+ if (key == '~') {
+ switch (escape_data[2]) {
+ case '1': /* \e[1~, home */
+ mapkey = 1;
+ break;
+ case '3': /* \e[3~, del */
+ mapkey = 4;
+ break;
+ case '4': /* \e[4~, end */
+ mapkey = 5;
+ break;
+ }
+ }
+ if (mapkey > 0) {
+ escape_data[0] = mapkey;
+ escape_data[1] = '\0';
+ }
+ escape_delay = 2;
+ continue;
+ }
+ }
+ break; /* A key to process */
+ }
+ return key;
+}
+
+/*
+ * kdb_read
+ *
+ * This function reads a string of characters, terminated by
+ * a newline, or by reaching the end of the supplied buffer,
+ * from the current kernel debugger console device.
+ * Parameters:
+ * buffer - Address of character buffer to receive input characters.
+ * bufsize - size, in bytes, of the character buffer
+ * Returns:
+ * Returns a pointer to the buffer containing the received
+ * character string. This string will be terminated by a
+ * newline character.
+ * Locking:
+ * No locks are required to be held upon entry to this
+ * function. It is not reentrant - it relies on the fact
+ * that while kdb is running on only one "master debug" cpu.
+ * Remarks:
+ *
+ * The buffer size must be >= 2. A buffer size of 2 means that the caller only
+ * wants a single key.
+ *
+ * An escape key could be the start of a vt100 control sequence such as \e[D
+ * (left arrow) or it could be a character in its own right. The standard
+ * method for detecting the difference is to wait for 2 seconds to see if there
+ * are any other characters. kdb is complicated by the lack of a timer service
+ * (interrupts are off), by multiple input sources and by the need to sometimes
+ * return after just one key. Escape sequence processing has to be done as
+ * states in the polling loop.
+ */
+
+static char *kdb_read(char *buffer, size_t bufsize)
+{
+ char *cp = buffer;
+ char *bufend = buffer+bufsize-2; /* Reserve space for newline
+ * and null byte */
+ char *lastchar;
+ char *p_tmp;
+ char tmp;
+ static char tmpbuffer[CMD_BUFLEN];
+ int len = strlen(buffer);
+ int len_tmp;
+ int tab = 0;
+ int count;
+ int i;
+ int diag, dtab_count;
+ int key;
+
+
+ diag = kdbgetintenv("DTABCOUNT", &dtab_count);
+ if (diag)
+ dtab_count = 30;
+
+ if (len > 0) {
+ cp += len;
+ if (*(buffer+len-1) == '\n')
+ cp--;
+ }
+
+ lastchar = cp;
+ *cp = '\0';
+ kdb_printf("%s", buffer);
+poll_again:
+ key = kdb_read_get_key(buffer, bufsize);
+ if (key == -1)
+ return buffer;
+ if (key != 9)
+ tab = 0;
+ switch (key) {
+ case 8: /* backspace */
+ if (cp > buffer) {
+ if (cp < lastchar) {
+ memcpy(tmpbuffer, cp, lastchar - cp);
+ memcpy(cp-1, tmpbuffer, lastchar - cp);
+ }
+ *(--lastchar) = '\0';
+ --cp;
+ kdb_printf("\b%s \r", cp);
+ tmp = *cp;
+ *cp = '\0';
+ kdb_printf(kdb_prompt_str);
+ kdb_printf("%s", buffer);
+ *cp = tmp;
+ }
+ break;
+ case 13: /* enter */
+ *lastchar++ = '\n';
+ *lastchar++ = '\0';
+ kdb_printf("\n");
+ return buffer;
+ case 4: /* Del */
+ if (cp < lastchar) {
+ memcpy(tmpbuffer, cp+1, lastchar - cp - 1);
+ memcpy(cp, tmpbuffer, lastchar - cp - 1);
+ *(--lastchar) = '\0';
+ kdb_printf("%s \r", cp);
+ tmp = *cp;
+ *cp = '\0';
+ kdb_printf(kdb_prompt_str);
+ kdb_printf("%s", buffer);
+ *cp = tmp;
+ }
+ break;
+ case 1: /* Home */
+ if (cp > buffer) {
+ kdb_printf("\r");
+ kdb_printf(kdb_prompt_str);
+ cp = buffer;
+ }
+ break;
+ case 5: /* End */
+ if (cp < lastchar) {
+ kdb_printf("%s", cp);
+ cp = lastchar;
+ }
+ break;
+ case 2: /* Left */
+ if (cp > buffer) {
+ kdb_printf("\b");
+ --cp;
+ }
+ break;
+ case 14: /* Down */
+ memset(tmpbuffer, ' ',
+ strlen(kdb_prompt_str) + (lastchar-buffer));
+ *(tmpbuffer+strlen(kdb_prompt_str) +
+ (lastchar-buffer)) = '\0';
+ kdb_printf("\r%s\r", tmpbuffer);
+ *lastchar = (char)key;
+ *(lastchar+1) = '\0';
+ return lastchar;
+ case 6: /* Right */
+ if (cp < lastchar) {
+ kdb_printf("%c", *cp);
+ ++cp;
+ }
+ break;
+ case 16: /* Up */
+ memset(tmpbuffer, ' ',
+ strlen(kdb_prompt_str) + (lastchar-buffer));
+ *(tmpbuffer+strlen(kdb_prompt_str) +
+ (lastchar-buffer)) = '\0';
+ kdb_printf("\r%s\r", tmpbuffer);
+ *lastchar = (char)key;
+ *(lastchar+1) = '\0';
+ return lastchar;
+ case 9: /* Tab */
+ if (tab < 2)
+ ++tab;
+ p_tmp = buffer;
+ while (*p_tmp == ' ')
+ p_tmp++;
+ if (p_tmp > cp)
+ break;
+ memcpy(tmpbuffer, p_tmp, cp-p_tmp);
+ *(tmpbuffer + (cp-p_tmp)) = '\0';
+ p_tmp = strrchr(tmpbuffer, ' ');
+ if (p_tmp)
+ ++p_tmp;
+ else
+ p_tmp = tmpbuffer;
+ len = strlen(p_tmp);
+ count = kallsyms_symbol_complete(p_tmp,
+ sizeof(tmpbuffer) -
+ (p_tmp - tmpbuffer));
+ if (tab == 2 && count > 0) {
+ kdb_printf("\n%d symbols are found.", count);
+ if (count > dtab_count) {
+ count = dtab_count;
+ kdb_printf(" But only first %d symbols will"
+ " be printed.\nYou can change the"
+ " environment variable DTABCOUNT.",
+ count);
+ }
+ kdb_printf("\n");
+ for (i = 0; i < count; i++) {
+ if (kallsyms_symbol_next(p_tmp, i) < 0)
+ break;
+ kdb_printf("%s ", p_tmp);
+ *(p_tmp + len) = '\0';
+ }
+ if (i >= dtab_count)
+ kdb_printf("...");
+ kdb_printf("\n");
+ kdb_printf(kdb_prompt_str);
+ kdb_printf("%s", buffer);
+ } else if (tab != 2 && count > 0) {
+ len_tmp = strlen(p_tmp);
+ strncpy(p_tmp+len_tmp, cp, lastchar-cp+1);
+ len_tmp = strlen(p_tmp);
+ strncpy(cp, p_tmp+len, len_tmp-len + 1);
+ len = len_tmp - len;
+ kdb_printf("%s", cp);
+ cp += len;
+ lastchar += len;
+ }
+ kdb_nextline = 1; /* reset output line number */
+ break;
+ default:
+ if (key >= 32 && lastchar < bufend) {
+ if (cp < lastchar) {
+ memcpy(tmpbuffer, cp, lastchar - cp);
+ memcpy(cp+1, tmpbuffer, lastchar - cp);
+ *++lastchar = '\0';
+ *cp = key;
+ kdb_printf("%s\r", cp);
+ ++cp;
+ tmp = *cp;
+ *cp = '\0';
+ kdb_printf(kdb_prompt_str);
+ kdb_printf("%s", buffer);
+ *cp = tmp;
+ } else {
+ *++lastchar = '\0';
+ *cp++ = key;
+ /* The kgdb transition check will hide
+ * printed characters if we think that
+ * kgdb is connecting, until the check
+ * fails */
+ if (!KDB_STATE(KGDB_TRANS))
+ kgdb_transition_check(buffer);
+ else
+ kdb_printf("%c", key);
+ }
+ /* Special escape to kgdb */
+ if (lastchar - buffer >= 5 &&
+ strcmp(lastchar - 5, "$?#3f") == 0) {
+ strcpy(buffer, "kgdb");
+ KDB_STATE_SET(DOING_KGDB);
+ return buffer;
+ }
+ if (lastchar - buffer >= 14 &&
+ strcmp(lastchar - 14, "$qSupported#37") == 0) {
+ strcpy(buffer, "kgdb");
+ KDB_STATE_SET(DOING_KGDB2);
+ return buffer;
+ }
+ }
+ break;
+ }
+ goto poll_again;
+}
+
+/*
+ * kdb_getstr
+ *
+ * Print the prompt string and read a command from the
+ * input device.
+ *
+ * Parameters:
+ * buffer Address of buffer to receive command
+ * bufsize Size of buffer in bytes
+ * prompt Pointer to string to use as prompt string
+ * Returns:
+ * Pointer to command buffer.
+ * Locking:
+ * None.
+ * Remarks:
+ * For SMP kernels, the processor number will be
+ * substituted for %d, %x or %o in the prompt.
+ */
+
+char *kdb_getstr(char *buffer, size_t bufsize, char *prompt)
+{
+ if (prompt && kdb_prompt_str != prompt)
+ strncpy(kdb_prompt_str, prompt, CMD_BUFLEN);
+ kdb_printf(kdb_prompt_str);
+ kdb_nextline = 1; /* Prompt and input resets line number */
+ return kdb_read(buffer, bufsize);
+}
+
+/*
+ * kdb_input_flush
+ *
+ * Get rid of any buffered console input.
+ *
+ * Parameters:
+ * none
+ * Returns:
+ * nothing
+ * Locking:
+ * none
+ * Remarks:
+ * Call this function whenever you want to flush input. If there is any
+ * outstanding input, it ignores all characters until there has been no
+ * data for approximately half a second.
+ */
+
+#define FLUSH_UDELAY 100
+#define FLUSH_DELAY (500000/FLUSH_UDELAY) /* 0.5 seconds worth of udelays */
+
+static void kdb_input_flush(void)
+{
+ get_char_func *f;
+ int flush_delay = 1;
+ while (flush_delay--) {
+ touch_nmi_watchdog();
+ for (f = &kdb_poll_funcs[0]; *f; ++f) {
+ if ((*f)() != -1) {
+ flush_delay = FLUSH_DELAY;
+ break;
+ }
+ }
+ if (flush_delay)
+ udelay(FLUSH_UDELAY);
+ }
+}
+
+/*
+ * kdb_printf
+ *
+ * Print a string to the output device(s).
+ *
+ * Parameters:
+ * printf-like format and optional args.
+ * Returns:
+ * 0
+ * Locking:
+ * None.
+ * Remarks:
+ * use 'kdbcons->write()' to avoid polluting 'log_buf' with
+ * kdb output.
+ *
+ * If the user is doing a cmd args | grep srch
+ * then kdb_grepping_flag is set.
+ * In that case we need to accumulate full lines (ending in \n) before
+ * searching for the pattern.
+ */
+
+static char kdb_buffer[256]; /* A bit too big to go on stack */
+static char *next_avail = kdb_buffer;
+static int size_avail;
+static int suspend_grep;
+
+/*
+ * search arg1 to see if it contains arg2
+ * (kdmain.c provides flags for ^pat and pat$)
+ *
+ * return 1 for found, 0 for not found
+ */
+static int kdb_search_string(char *searched, char *searchfor)
+{
+ char firstchar, *cp;
+ int len1, len2;
+
+ /* not counting the newline at the end of "searched" */
+ len1 = strlen(searched)-1;
+ len2 = strlen(searchfor);
+ if (len1 < len2)
+ return 0;
+ if (kdb_grep_leading && kdb_grep_trailing && len1 != len2)
+ return 0;
+ if (kdb_grep_leading) {
+ if (!strncmp(searched, searchfor, len2))
+ return 1;
+ } else if (kdb_grep_trailing) {
+ if (!strncmp(searched+len1-len2, searchfor, len2))
+ return 1;
+ } else {
+ firstchar = *searchfor;
+ cp = searched;
+ while ((cp = strchr(cp, firstchar))) {
+ if (!strncmp(cp, searchfor, len2))
+ return 1;
+ cp++;
+ }
+ }
+ return 0;
+}
+
+int kdb_printf(const char *fmt, ...)
+{
+ va_list ap;
+ int diag;
+ int linecount;
+ int logging, saved_loglevel = 0;
+ int got_printf_lock = 0;
+ int retlen = 0;
+ int fnd, len;
+ char *cp, *cp2, *cphold = NULL, replaced_byte = ' ';
+ char *moreprompt = "more> ";
+ struct console *c = console_drivers;
+ static DEFINE_SPINLOCK(kdb_printf_lock);
+ unsigned long uninitialized_var(flags);
+
+ preempt_disable();
+ /* Serialize kdb_printf if multiple cpus try to write at once.
+ * But if any cpu goes recursive in kdb, just print the output,
+ * even if it is interleaved with any other text.
+ */
+ if (!KDB_STATE(PRINTF_LOCK)) {
+ KDB_STATE_SET(PRINTF_LOCK);
+ spin_lock_irqsave(&kdb_printf_lock, flags);
+ got_printf_lock = 1;
+ atomic_inc(&kdb_event);
+ } else {
+ __acquire(kdb_printf_lock);
+ }
+
+ diag = kdbgetintenv("LINES", &linecount);
+ if (diag || linecount <= 1)
+ linecount = 24;
+
+ diag = kdbgetintenv("LOGGING", &logging);
+ if (diag)
+ logging = 0;
+
+ if (!kdb_grepping_flag || suspend_grep) {
+ /* normally, every vsnprintf starts a new buffer */
+ next_avail = kdb_buffer;
+ size_avail = sizeof(kdb_buffer);
+ }
+ va_start(ap, fmt);
+ vsnprintf(next_avail, size_avail, fmt, ap);
+ va_end(ap);
+
+ /*
+ * If kdb_parse() found that the command was cmd xxx | grep yyy
+ * then kdb_grepping_flag is set, and kdb_grep_string contains yyy
+ *
+ * Accumulate the print data up to a newline before searching it.
+ * (vsnprintf does null-terminate the string that it generates)
+ */
+
+ /* skip the search if prints are temporarily unconditional */
+ if (!suspend_grep && kdb_grepping_flag) {
+ cp = strchr(kdb_buffer, '\n');
+ if (!cp) {
+ /*
+ * Special cases that don't end with newlines
+ * but should be written without one:
+ * The "[nn]kdb> " prompt should
+ * appear at the front of the buffer.
+ *
+ * The "[nn]more " prompt should also be
+ * (MOREPROMPT -> moreprompt)
+ * written * but we print that ourselves,
+ * we set the suspend_grep flag to make
+ * it unconditional.
+ *
+ */
+ if (next_avail == kdb_buffer) {
+ /*
+ * these should occur after a newline,
+ * so they will be at the front of the
+ * buffer
+ */
+ cp2 = kdb_buffer;
+ len = strlen(kdb_prompt_str);
+ if (!strncmp(cp2, kdb_prompt_str, len)) {
+ /*
+ * We're about to start a new
+ * command, so we can go back
+ * to normal mode.
+ */
+ kdb_grepping_flag = 0;
+ goto kdb_printit;
+ }
+ }
+ /* no newline; don't search/write the buffer
+ until one is there */
+ len = strlen(kdb_buffer);
+ next_avail = kdb_buffer + len;
+ size_avail = sizeof(kdb_buffer) - len;
+ goto kdb_print_out;
+ }
+
+ /*
+ * The newline is present; print through it or discard
+ * it, depending on the results of the search.
+ */
+ cp++; /* to byte after the newline */
+ replaced_byte = *cp; /* remember what/where it was */
+ cphold = cp;
+ *cp = '\0'; /* end the string for our search */
+
+ /*
+ * We now have a newline at the end of the string
+ * Only continue with this output if it contains the
+ * search string.
+ */
+ fnd = kdb_search_string(kdb_buffer, kdb_grep_string);
+ if (!fnd) {
+ /*
+ * At this point the complete line at the start
+ * of kdb_buffer can be discarded, as it does
+ * not contain what the user is looking for.
+ * Shift the buffer left.
+ */
+ *cphold = replaced_byte;
+ strcpy(kdb_buffer, cphold);
+ len = strlen(kdb_buffer);
+ next_avail = kdb_buffer + len;
+ size_avail = sizeof(kdb_buffer) - len;
+ goto kdb_print_out;
+ }
+ /*
+ * at this point the string is a full line and
+ * should be printed, up to the null.
+ */
+ }
+kdb_printit:
+
+ /*
+ * Write to all consoles.
+ */
+ retlen = strlen(kdb_buffer);
+ while (c) {
+ c->write(c, kdb_buffer, retlen);
+ touch_nmi_watchdog();
+ c = c->next;
+ }
+ if (logging) {
+ saved_loglevel = console_loglevel;
+ console_loglevel = 0;
+ printk(KERN_INFO "%s", kdb_buffer);
+ }
+
+ if (KDB_STATE(PAGER) && strchr(kdb_buffer, '\n'))
+ kdb_nextline++;
+
+ /* check for having reached the LINES number of printed lines */
+ if (kdb_nextline == linecount) {
+ char buf1[16] = "";
+#if defined(CONFIG_SMP)
+ char buf2[32];
+#endif
+
+ /* Watch out for recursion here. Any routine that calls
+ * kdb_printf will come back through here. And kdb_read
+ * uses kdb_printf to echo on serial consoles ...
+ */
+ kdb_nextline = 1; /* In case of recursion */
+
+ /*
+ * Pause until cr.
+ */
+ moreprompt = kdbgetenv("MOREPROMPT");
+ if (moreprompt == NULL)
+ moreprompt = "more> ";
+
+#if defined(CONFIG_SMP)
+ if (strchr(moreprompt, '%')) {
+ sprintf(buf2, moreprompt, get_cpu());
+ put_cpu();
+ moreprompt = buf2;
+ }
+#endif
+
+ kdb_input_flush();
+ c = console_drivers;
+
+ while (c) {
+ c->write(c, moreprompt, strlen(moreprompt));
+ touch_nmi_watchdog();
+ c = c->next;
+ }
+
+ if (logging)
+ printk("%s", moreprompt);
+
+ kdb_read(buf1, 2); /* '2' indicates to return
+ * immediately after getting one key. */
+ kdb_nextline = 1; /* Really set output line 1 */
+
+ /* empty and reset the buffer: */
+ kdb_buffer[0] = '\0';
+ next_avail = kdb_buffer;
+ size_avail = sizeof(kdb_buffer);
+ if ((buf1[0] == 'q') || (buf1[0] == 'Q')) {
+ /* user hit q or Q */
+ KDB_FLAG_SET(CMD_INTERRUPT); /* command interrupted */
+ KDB_STATE_CLEAR(PAGER);
+ /* end of command output; back to normal mode */
+ kdb_grepping_flag = 0;
+ kdb_printf("\n");
+ } else if (buf1[0] == ' ') {
+ kdb_printf("\n");
+ suspend_grep = 1; /* for this recursion */
+ } else if (buf1[0] == '\n') {
+ kdb_nextline = linecount - 1;
+ kdb_printf("\r");
+ suspend_grep = 1; /* for this recursion */
+ } else if (buf1[0] && buf1[0] != '\n') {
+ /* user hit something other than enter */
+ suspend_grep = 1; /* for this recursion */
+ kdb_printf("\nOnly 'q' or 'Q' are processed at more "
+ "prompt, input ignored\n");
+ } else if (kdb_grepping_flag) {
+ /* user hit enter */
+ suspend_grep = 1; /* for this recursion */
+ kdb_printf("\n");
+ }
+ kdb_input_flush();
+ }
+
+ /*
+ * For grep searches, shift the printed string left.
+ * replaced_byte contains the character that was overwritten with
+ * the terminating null, and cphold points to the null.
+ * Then adjust the notion of available space in the buffer.
+ */
+ if (kdb_grepping_flag && !suspend_grep) {
+ *cphold = replaced_byte;
+ strcpy(kdb_buffer, cphold);
+ len = strlen(kdb_buffer);
+ next_avail = kdb_buffer + len;
+ size_avail = sizeof(kdb_buffer) - len;
+ }
+
+kdb_print_out:
+ suspend_grep = 0; /* end of what may have been a recursive call */
+ if (logging)
+ console_loglevel = saved_loglevel;
+ if (KDB_STATE(PRINTF_LOCK) && got_printf_lock) {
+ got_printf_lock = 0;
+ spin_unlock_irqrestore(&kdb_printf_lock, flags);
+ KDB_STATE_CLEAR(PRINTF_LOCK);
+ atomic_dec(&kdb_event);
+ } else {
+ __release(kdb_printf_lock);
+ }
+ preempt_enable();
+ return retlen;
+}
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
new file mode 100644
index 0000000..6c9826a
--- /dev/null
+++ b/kernel/debug/kdb/kdb_main.c
@@ -0,0 +1,2850 @@
+/*
+ * Kernel Debugger Architecture Independent Main Code
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
+ * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/sysrq.h>
+#include <linux/smp.h>
+#include <linux/utsname.h>
+#include <linux/vmalloc.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/kallsyms.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/notifier.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/nmi.h>
+#include <linux/time.h>
+#include <linux/ptrace.h>
+#include <linux/sysctl.h>
+#include <linux/cpu.h>
+#include <linux/kdebug.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+#include <linux/swap.h>
+#include "kdb_private.h"
+
+#define GREP_LEN 256
+char kdb_grep_string[GREP_LEN];
+int kdb_grepping_flag;
+EXPORT_SYMBOL(kdb_grepping_flag);
+int kdb_grep_leading;
+int kdb_grep_trailing;
+
+/*
+ * Kernel debugger state flags
+ */
+int kdb_flags;
+atomic_t kdb_event;
+
+/*
+ * kdb_lock protects updates to kdb_initial_cpu. Used to
+ * single thread processors through the kernel debugger.
+ */
+int kdb_initial_cpu = -1; /* cpu number that owns kdb */
+int kdb_seqno = 2; /* how many times kdb has been entered */
+
+int kdb_nextline = 1;
+int kdb_state[NR_CPUS]; /* Per cpu state */
+
+struct task_struct *kdb_current_task;
+EXPORT_SYMBOL(kdb_current_task);
+struct pt_regs *kdb_current_regs;
+
+const char *kdb_diemsg;
+static int kdb_go_count;
+#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
+static unsigned int kdb_continue_catastrophic =
+ CONFIG_KDB_CONTINUE_CATASTROPHIC;
+#else
+static unsigned int kdb_continue_catastrophic;
+#endif
+
+ /*
+ * kdb_commands describes the available commands.
+ */
+static kdbtab_t *kdb_commands;
+static int kdb_max_commands;
+
+typedef struct _kdbmsg {
+ int km_diag; /* kdb diagnostic */
+ char *km_msg; /* Corresponding message text */
+} kdbmsg_t;
+
+#define KDBMSG(msgnum, text) \
+ { KDB_##msgnum, text }
+
+static kdbmsg_t kdbmsgs[] = {
+ KDBMSG(NOTFOUND, "Command Not Found"),
+ KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
+ KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
+ "8 is only allowed on 64 bit systems"),
+ KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
+ KDBMSG(NOTENV, "Cannot find environment variable"),
+ KDBMSG(NOENVVALUE, "Environment variable should have value"),
+ KDBMSG(NOTIMP, "Command not implemented"),
+ KDBMSG(ENVFULL, "Environment full"),
+ KDBMSG(ENVBUFFULL, "Environment buffer full"),
+ KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
+#ifdef CONFIG_CPU_XSCALE
+ KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
+#else
+ KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
+#endif
+ KDBMSG(DUPBPT, "Duplicate breakpoint address"),
+ KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
+ KDBMSG(BADMODE, "Invalid IDMODE"),
+ KDBMSG(BADINT, "Illegal numeric value"),
+ KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
+ KDBMSG(BADREG, "Invalid register name"),
+ KDBMSG(BADCPUNUM, "Invalid cpu number"),
+ KDBMSG(BADLENGTH, "Invalid length field"),
+ KDBMSG(NOBP, "No Breakpoint exists"),
+ KDBMSG(BADADDR, "Invalid address"),
+};
+#undef KDBMSG
+
+static const int __nkdb_err = sizeof(kdbmsgs) / sizeof(kdbmsg_t);
+
+
+/*
+ * Initial environment. This is all kept static and local to
+ * this file. We don't want to rely on the memory allocation
+ * mechanisms in the kernel, so we use a very limited allocate-only
+ * heap for new and altered environment variables. The entire
+ * environment is limited to a fixed number of entries (add more
+ * to __env[] if required) and a fixed amount of heap (add more to
+ * KDB_ENVBUFSIZE if required).
+ */
+
+static char *__env[] = {
+#if defined(CONFIG_SMP)
+ "PROMPT=[%d]kdb> ",
+ "MOREPROMPT=[%d]more> ",
+#else
+ "PROMPT=kdb> ",
+ "MOREPROMPT=more> ",
+#endif
+ "RADIX=16",
+ "MDCOUNT=8", /* lines of md output */
+ "BTARGS=9", /* 9 possible args in bt */
+ KDB_PLATFORM_ENV,
+ "DTABCOUNT=30",
+ "NOSECT=1",
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+ (char *)0,
+};
+
+static const int __nenv = (sizeof(__env) / sizeof(char *));
+
+struct task_struct *kdb_curr_task(int cpu)
+{
+ struct task_struct *p = curr_task(cpu);
+#ifdef _TIF_MCA_INIT
+ struct kdb_running_process *krp = kdb_running_process + cpu;
+ if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && krp->p)
+ p = krp->p;
+#endif
+ return p;
+}
+
+/*
+ * kdbgetenv - This function will return the character string value of
+ * an environment variable.
+ * Parameters:
+ * match A character string representing an environment variable.
+ * Returns:
+ * NULL No environment variable matches 'match'
+ * char* Pointer to string value of environment variable.
+ */
+char *kdbgetenv(const char *match)
+{
+ char **ep = __env;
+ int matchlen = strlen(match);
+ int i;
+
+ for (i = 0; i < __nenv; i++) {
+ char *e = *ep++;
+
+ if (!e)
+ continue;
+
+ if ((strncmp(match, e, matchlen) == 0)
+ && ((e[matchlen] == '\0')
+ || (e[matchlen] == '='))) {
+ char *cp = strchr(e, '=');
+ return cp ? ++cp : "";
+ }
+ }
+ return NULL;
+}
+
+/*
+ * kdballocenv - This function is used to allocate bytes for
+ * environment entries.
+ * Parameters:
+ * match A character string representing a numeric value
+ * Outputs:
+ * *value the unsigned long representation of the env variable 'match'
+ * Returns:
+ * Zero on success, a kdb diagnostic on failure.
+ * Remarks:
+ * We use a static environment buffer (envbuffer) to hold the values
+ * of dynamically generated environment variables (see kdb_set). Buffer
+ * space once allocated is never free'd, so over time, the amount of space
+ * (currently 512 bytes) will be exhausted if env variables are changed
+ * frequently.
+ */
+static char *kdballocenv(size_t bytes)
+{
+#define KDB_ENVBUFSIZE 512
+ static char envbuffer[KDB_ENVBUFSIZE];
+ static int envbufsize;
+ char *ep = NULL;
+
+ if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
+ ep = &envbuffer[envbufsize];
+ envbufsize += bytes;
+ }
+ return ep;
+}
+
+/*
+ * kdbgetulenv - This function will return the value of an unsigned
+ * long-valued environment variable.
+ * Parameters:
+ * match A character string representing a numeric value
+ * Outputs:
+ * *value the unsigned long represntation of the env variable 'match'
+ * Returns:
+ * Zero on success, a kdb diagnostic on failure.
+ */
+static int kdbgetulenv(const char *match, unsigned long *value)
+{
+ char *ep;
+
+ ep = kdbgetenv(match);
+ if (!ep)
+ return KDB_NOTENV;
+ if (strlen(ep) == 0)
+ return KDB_NOENVVALUE;
+
+ *value = simple_strtoul(ep, NULL, 0);
+
+ return 0;
+}
+
+/*
+ * kdbgetintenv - This function will return the value of an
+ * integer-valued environment variable.
+ * Parameters:
+ * match A character string representing an integer-valued env variable
+ * Outputs:
+ * *value the integer representation of the environment variable 'match'
+ * Returns:
+ * Zero on success, a kdb diagnostic on failure.
+ */
+int kdbgetintenv(const char *match, int *value)
+{
+ unsigned long val;
+ int diag;
+
+ diag = kdbgetulenv(match, &val);
+ if (!diag)
+ *value = (int) val;
+ return diag;
+}
+
+/*
+ * kdbgetularg - This function will convert a numeric string into an
+ * unsigned long value.
+ * Parameters:
+ * arg A character string representing a numeric value
+ * Outputs:
+ * *value the unsigned long represntation of arg.
+ * Returns:
+ * Zero on success, a kdb diagnostic on failure.
+ */
+int kdbgetularg(const char *arg, unsigned long *value)
+{
+ char *endp;
+ unsigned long val;
+
+ val = simple_strtoul(arg, &endp, 0);
+
+ if (endp == arg) {
+ /*
+ * Try base 16, for us folks too lazy to type the
+ * leading 0x...
+ */
+ val = simple_strtoul(arg, &endp, 16);
+ if (endp == arg)
+ return KDB_BADINT;
+ }
+
+ *value = val;
+
+ return 0;
+}
+
+/*
+ * kdb_set - This function implements the 'set' command. Alter an
+ * existing environment variable or create a new one.
+ */
+int kdb_set(int argc, const char **argv)
+{
+ int i;
+ char *ep;
+ size_t varlen, vallen;
+
+ /*
+ * we can be invoked two ways:
+ * set var=value argv[1]="var", argv[2]="value"
+ * set var = value argv[1]="var", argv[2]="=", argv[3]="value"
+ * - if the latter, shift 'em down.
+ */
+ if (argc == 3) {
+ argv[2] = argv[3];
+ argc--;
+ }
+
+ if (argc != 2)
+ return KDB_ARGCOUNT;
+
+ /*
+ * Check for internal variables
+ */
+ if (strcmp(argv[1], "KDBDEBUG") == 0) {
+ unsigned int debugflags;
+ char *cp;
+
+ debugflags = simple_strtoul(argv[2], &cp, 0);
+ if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
+ kdb_printf("kdb: illegal debug flags '%s'\n",
+ argv[2]);
+ return 0;
+ }
+ kdb_flags = (kdb_flags &
+ ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
+ | (debugflags << KDB_DEBUG_FLAG_SHIFT);
+
+ return 0;
+ }
+
+ /*
+ * Tokenizer squashed the '=' sign. argv[1] is variable
+ * name, argv[2] = value.
+ */
+ varlen = strlen(argv[1]);
+ vallen = strlen(argv[2]);
+ ep = kdballocenv(varlen + vallen + 2);
+ if (ep == (char *)0)
+ return KDB_ENVBUFFULL;
+
+ sprintf(ep, "%s=%s", argv[1], argv[2]);
+
+ ep[varlen+vallen+1] = '\0';
+
+ for (i = 0; i < __nenv; i++) {
+ if (__env[i]
+ && ((strncmp(__env[i], argv[1], varlen) == 0)
+ && ((__env[i][varlen] == '\0')
+ || (__env[i][varlen] == '=')))) {
+ __env[i] = ep;
+ return 0;
+ }
+ }
+
+ /*
+ * Wasn't existing variable. Fit into slot.
+ */
+ for (i = 0; i < __nenv-1; i++) {
+ if (__env[i] == (char *)0) {
+ __env[i] = ep;
+ return 0;
+ }
+ }
+
+ return KDB_ENVFULL;
+}
+
+static int kdb_check_regs(void)
+{
+ if (!kdb_current_regs) {
+ kdb_printf("No current kdb registers."
+ " You may need to select another task\n");
+ return KDB_BADREG;
+ }
+ return 0;
+}
+
+/*
+ * kdbgetaddrarg - This function is responsible for parsing an
+ * address-expression and returning the value of the expression,
+ * symbol name, and offset to the caller.
+ *
+ * The argument may consist of a numeric value (decimal or
+ * hexidecimal), a symbol name, a register name (preceeded by the
+ * percent sign), an environment variable with a numeric value
+ * (preceeded by a dollar sign) or a simple arithmetic expression
+ * consisting of a symbol name, +/-, and a numeric constant value
+ * (offset).
+ * Parameters:
+ * argc - count of arguments in argv
+ * argv - argument vector
+ * *nextarg - index to next unparsed argument in argv[]
+ * regs - Register state at time of KDB entry
+ * Outputs:
+ * *value - receives the value of the address-expression
+ * *offset - receives the offset specified, if any
+ * *name - receives the symbol name, if any
+ * *nextarg - index to next unparsed argument in argv[]
+ * Returns:
+ * zero is returned on success, a kdb diagnostic code is
+ * returned on error.
+ */
+int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
+ unsigned long *value, long *offset,
+ char **name)
+{
+ unsigned long addr;
+ unsigned long off = 0;
+ int positive;
+ int diag;
+ int found = 0;
+ char *symname;
+ char symbol = '\0';
+ char *cp;
+ kdb_symtab_t symtab;
+
+ /*
+ * Process arguments which follow the following syntax:
+ *
+ * symbol | numeric-address [+/- numeric-offset]
+ * %register
+ * $environment-variable
+ */
+
+ if (*nextarg > argc)
+ return KDB_ARGCOUNT;
+
+ symname = (char *)argv[*nextarg];
+
+ /*
+ * If there is no whitespace between the symbol
+ * or address and the '+' or '-' symbols, we
+ * remember the character and replace it with a
+ * null so the symbol/value can be properly parsed
+ */
+ cp = strpbrk(symname, "+-");
+ if (cp != NULL) {
+ symbol = *cp;
+ *cp++ = '\0';
+ }
+
+ if (symname[0] == '$') {
+ diag = kdbgetulenv(&symname[1], &addr);
+ if (diag)
+ return diag;
+ } else if (symname[0] == '%') {
+ diag = kdb_check_regs();
+ if (diag)
+ return diag;
+ /* Implement register values with % at a later time as it is
+ * arch optional.
+ */
+ return KDB_NOTIMP;
+ } else {
+ found = kdbgetsymval(symname, &symtab);
+ if (found) {
+ addr = symtab.sym_start;
+ } else {
+ diag = kdbgetularg(argv[*nextarg], &addr);
+ if (diag)
+ return diag;
+ }
+ }
+
+ if (!found)
+ found = kdbnearsym(addr, &symtab);
+
+ (*nextarg)++;
+
+ if (name)
+ *name = symname;
+ if (value)
+ *value = addr;
+ if (offset && name && *name)
+ *offset = addr - symtab.sym_start;
+
+ if ((*nextarg > argc)
+ && (symbol == '\0'))
+ return 0;
+
+ /*
+ * check for +/- and offset
+ */
+
+ if (symbol == '\0') {
+ if ((argv[*nextarg][0] != '+')
+ && (argv[*nextarg][0] != '-')) {
+ /*
+ * Not our argument. Return.
+ */
+ return 0;
+ } else {
+ positive = (argv[*nextarg][0] == '+');
+ (*nextarg)++;
+ }
+ } else
+ positive = (symbol == '+');
+
+ /*
+ * Now there must be an offset!
+ */
+ if ((*nextarg > argc)
+ && (symbol == '\0')) {
+ return KDB_INVADDRFMT;
+ }
+
+ if (!symbol) {
+ cp = (char *)argv[*nextarg];
+ (*nextarg)++;
+ }
+
+ diag = kdbgetularg(cp, &off);
+ if (diag)
+ return diag;
+
+ if (!positive)
+ off = -off;
+
+ if (offset)
+ *offset += off;
+
+ if (value)
+ *value += off;
+
+ return 0;
+}
+
+static void kdb_cmderror(int diag)
+{
+ int i;
+
+ if (diag >= 0) {
+ kdb_printf("no error detected (diagnostic is %d)\n", diag);
+ return;
+ }
+
+ for (i = 0; i < __nkdb_err; i++) {
+ if (kdbmsgs[i].km_diag == diag) {
+ kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
+ return;
+ }
+ }
+
+ kdb_printf("Unknown diag %d\n", -diag);
+}
+
+/*
+ * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
+ * command which defines one command as a set of other commands,
+ * terminated by endefcmd. kdb_defcmd processes the initial
+ * 'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
+ * the following commands until 'endefcmd'.
+ * Inputs:
+ * argc argument count
+ * argv argument vector
+ * Returns:
+ * zero for success, a kdb diagnostic if error
+ */
+struct defcmd_set {
+ int count;
+ int usable;
+ char *name;
+ char *usage;
+ char *help;
+ char **command;
+};
+static struct defcmd_set *defcmd_set;
+static int defcmd_set_count;
+static int defcmd_in_progress;
+
+/* Forward references */
+static int kdb_exec_defcmd(int argc, const char **argv);
+
+static int kdb_defcmd2(const char *cmdstr, const char *argv0)
+{
+ struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
+ char **save_command = s->command;
+ if (strcmp(argv0, "endefcmd") == 0) {
+ defcmd_in_progress = 0;
+ if (!s->count)
+ s->usable = 0;
+ if (s->usable)
+ kdb_register(s->name, kdb_exec_defcmd,
+ s->usage, s->help, 0);
+ return 0;
+ }
+ if (!s->usable)
+ return KDB_NOTIMP;
+ s->command = kmalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB);
+ if (!s->command) {
+ kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
+ cmdstr);
+ s->usable = 0;
+ return KDB_NOTIMP;
+ }
+ memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
+ s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
+ kfree(save_command);
+ return 0;
+}
+
+static int kdb_defcmd(int argc, const char **argv)
+{
+ struct defcmd_set *save_defcmd_set = defcmd_set, *s;
+ if (defcmd_in_progress) {
+ kdb_printf("kdb: nested defcmd detected, assuming missing "
+ "endefcmd\n");
+ kdb_defcmd2("endefcmd", "endefcmd");
+ }
+ if (argc == 0) {
+ int i;
+ for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
+ kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
+ s->usage, s->help);
+ for (i = 0; i < s->count; ++i)
+ kdb_printf("%s", s->command[i]);
+ kdb_printf("endefcmd\n");
+ }
+ return 0;
+ }
+ if (argc != 3)
+ return KDB_ARGCOUNT;
+ defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set),
+ GFP_KDB);
+ if (!defcmd_set) {
+ kdb_printf("Could not allocate new defcmd_set entry for %s\n",
+ argv[1]);
+ defcmd_set = save_defcmd_set;
+ return KDB_NOTIMP;
+ }
+ memcpy(defcmd_set, save_defcmd_set,
+ defcmd_set_count * sizeof(*defcmd_set));
+ kfree(save_defcmd_set);
+ s = defcmd_set + defcmd_set_count;
+ memset(s, 0, sizeof(*s));
+ s->usable = 1;
+ s->name = kdb_strdup(argv[1], GFP_KDB);
+ s->usage = kdb_strdup(argv[2], GFP_KDB);
+ s->help = kdb_strdup(argv[3], GFP_KDB);
+ if (s->usage[0] == '"') {
+ strcpy(s->usage, s->usage+1);
+ s->usage[strlen(s->usage)-1] = '\0';
+ }
+ if (s->help[0] == '"') {
+ strcpy(s->help, s->help+1);
+ s->help[strlen(s->help)-1] = '\0';
+ }
+ ++defcmd_set_count;
+ defcmd_in_progress = 1;
+ return 0;
+}
+
+/*
+ * kdb_exec_defcmd - Execute the set of commands associated with this
+ * defcmd name.
+ * Inputs:
+ * argc argument count
+ * argv argument vector
+ * Returns:
+ * zero for success, a kdb diagnostic if error
+ */
+static int kdb_exec_defcmd(int argc, const char **argv)
+{
+ int i, ret;
+ struct defcmd_set *s;
+ if (argc != 0)
+ return KDB_ARGCOUNT;
+ for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
+ if (strcmp(s->name, argv[0]) == 0)
+ break;
+ }
+ if (i == defcmd_set_count) {
+ kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
+ argv[0]);
+ return KDB_NOTIMP;
+ }
+ for (i = 0; i < s->count; ++i) {
+ /* Recursive use of kdb_parse, do not use argv after
+ * this point */
+ argv = NULL;
+ kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
+ ret = kdb_parse(s->command[i]);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/* Command history */
+#define KDB_CMD_HISTORY_COUNT 32
+#define CMD_BUFLEN 200 /* kdb_printf: max printline
+ * size == 256 */
+static unsigned int cmd_head, cmd_tail;
+static unsigned int cmdptr;
+static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
+static char cmd_cur[CMD_BUFLEN];
+
+/*
+ * The "str" argument may point to something like | grep xyz
+ */
+static void parse_grep(const char *str)
+{
+ int len;
+ char *cp = (char *)str, *cp2;
+
+ /* sanity check: we should have been called with the \ first */
+ if (*cp != '|')
+ return;
+ cp++;
+ while (isspace(*cp))
+ cp++;
+ if (strncmp(cp, "grep ", 5)) {
+ kdb_printf("invalid 'pipe', see grephelp\n");
+ return;
+ }
+ cp += 5;
+ while (isspace(*cp))
+ cp++;
+ cp2 = strchr(cp, '\n');
+ if (cp2)
+ *cp2 = '\0'; /* remove the trailing newline */
+ len = strlen(cp);
+ if (len == 0) {
+ kdb_printf("invalid 'pipe', see grephelp\n");
+ return;
+ }
+ /* now cp points to a nonzero length search string */
+ if (*cp == '"') {
+ /* allow it be "x y z" by removing the "'s - there must
+ be two of them */
+ cp++;
+ cp2 = strchr(cp, '"');
+ if (!cp2) {
+ kdb_printf("invalid quoted string, see grephelp\n");
+ return;
+ }
+ *cp2 = '\0'; /* end the string where the 2nd " was */
+ }
+ kdb_grep_leading = 0;
+ if (*cp == '^') {
+ kdb_grep_leading = 1;
+ cp++;
+ }
+ len = strlen(cp);
+ kdb_grep_trailing = 0;
+ if (*(cp+len-1) == '$') {
+ kdb_grep_trailing = 1;
+ *(cp+len-1) = '\0';
+ }
+ len = strlen(cp);
+ if (!len)
+ return;
+ if (len >= GREP_LEN) {
+ kdb_printf("search string too long\n");
+ return;
+ }
+ strcpy(kdb_grep_string, cp);
+ kdb_grepping_flag++;
+ return;
+}
+
+/*
+ * kdb_parse - Parse the command line, search the command table for a
+ * matching command and invoke the command function. This
+ * function may be called recursively, if it is, the second call
+ * will overwrite argv and cbuf. It is the caller's
+ * responsibility to save their argv if they recursively call
+ * kdb_parse().
+ * Parameters:
+ * cmdstr The input command line to be parsed.
+ * regs The registers at the time kdb was entered.
+ * Returns:
+ * Zero for success, a kdb diagnostic if failure.
+ * Remarks:
+ * Limited to 20 tokens.
+ *
+ * Real rudimentary tokenization. Basically only whitespace
+ * is considered a token delimeter (but special consideration
+ * is taken of the '=' sign as used by the 'set' command).
+ *
+ * The algorithm used to tokenize the input string relies on
+ * there being at least one whitespace (or otherwise useless)
+ * character between tokens as the character immediately following
+ * the token is altered in-place to a null-byte to terminate the
+ * token string.
+ */
+
+#define MAXARGC 20
+
+int kdb_parse(const char *cmdstr)
+{
+ static char *argv[MAXARGC];
+ static int argc;
+ static char cbuf[CMD_BUFLEN+2];
+ char *cp;
+ char *cpp, quoted;
+ kdbtab_t *tp;
+ int i, escaped, ignore_errors = 0, check_grep;
+
+ /*
+ * First tokenize the command string.
+ */
+ cp = (char *)cmdstr;
+ kdb_grepping_flag = check_grep = 0;
+
+ if (KDB_FLAG(CMD_INTERRUPT)) {
+ /* Previous command was interrupted, newline must not
+ * repeat the command */
+ KDB_FLAG_CLEAR(CMD_INTERRUPT);
+ KDB_STATE_SET(PAGER);
+ argc = 0; /* no repeat */
+ }
+
+ if (*cp != '\n' && *cp != '\0') {
+ argc = 0;
+ cpp = cbuf;
+ while (*cp) {
+ /* skip whitespace */
+ while (isspace(*cp))
+ cp++;
+ if ((*cp == '\0') || (*cp == '\n') ||
+ (*cp == '#' && !defcmd_in_progress))
+ break;
+ /* special case: check for | grep pattern */
+ if (*cp == '|') {
+ check_grep++;
+ break;
+ }
+ if (cpp >= cbuf + CMD_BUFLEN) {
+ kdb_printf("kdb_parse: command buffer "
+ "overflow, command ignored\n%s\n",
+ cmdstr);
+ return KDB_NOTFOUND;
+ }
+ if (argc >= MAXARGC - 1) {
+ kdb_printf("kdb_parse: too many arguments, "
+ "command ignored\n%s\n", cmdstr);
+ return KDB_NOTFOUND;
+ }
+ argv[argc++] = cpp;
+ escaped = 0;
+ quoted = '\0';
+ /* Copy to next unquoted and unescaped
+ * whitespace or '=' */
+ while (*cp && *cp != '\n' &&
+ (escaped || quoted || !isspace(*cp))) {
+ if (cpp >= cbuf + CMD_BUFLEN)
+ break;
+ if (escaped) {
+ escaped = 0;
+ *cpp++ = *cp++;
+ continue;
+ }
+ if (*cp == '\\') {
+ escaped = 1;
+ ++cp;
+ continue;
+ }
+ if (*cp == quoted)
+ quoted = '\0';
+ else if (*cp == '\'' || *cp == '"')
+ quoted = *cp;
+ *cpp = *cp++;
+ if (*cpp == '=' && !quoted)
+ break;
+ ++cpp;
+ }
+ *cpp++ = '\0'; /* Squash a ws or '=' character */
+ }
+ }
+ if (!argc)
+ return 0;
+ if (check_grep)
+ parse_grep(cp);
+ if (defcmd_in_progress) {
+ int result = kdb_defcmd2(cmdstr, argv[0]);
+ if (!defcmd_in_progress) {
+ argc = 0; /* avoid repeat on endefcmd */
+ *(argv[0]) = '\0';
+ }
+ return result;
+ }
+ if (argv[0][0] == '-' && argv[0][1] &&
+ (argv[0][1] < '0' || argv[0][1] > '9')) {
+ ignore_errors = 1;
+ ++argv[0];
+ }
+
+ for (tp = kdb_commands, i = 0; i < kdb_max_commands; i++, tp++) {
+ if (tp->cmd_name) {
+ /*
+ * If this command is allowed to be abbreviated,
+ * check to see if this is it.
+ */
+
+ if (tp->cmd_minlen
+ && (strlen(argv[0]) <= tp->cmd_minlen)) {
+ if (strncmp(argv[0],
+ tp->cmd_name,
+ tp->cmd_minlen) == 0) {
+ break;
+ }
+ }
+
+ if (strcmp(argv[0], tp->cmd_name) == 0)
+ break;
+ }
+ }
+
+ /*
+ * If we don't find a command by this name, see if the first
+ * few characters of this match any of the known commands.
+ * e.g., md1c20 should match md.
+ */
+ if (i == kdb_max_commands) {
+ for (tp = kdb_commands, i = 0; i < kdb_max_commands;
+ i++, tp++) {
+ if (tp->cmd_name) {
+ if (strncmp(argv[0],
+ tp->cmd_name,
+ strlen(tp->cmd_name)) == 0) {
+ break;
+ }
+ }
+ }
+ }
+
+ if (i < kdb_max_commands) {
+ int result;
+ KDB_STATE_SET(CMD);
+ result = (*tp->cmd_func)(argc-1, (const char **)argv);
+ if (result && ignore_errors && result > KDB_CMD_GO)
+ result = 0;
+ KDB_STATE_CLEAR(CMD);
+ switch (tp->cmd_repeat) {
+ case KDB_REPEAT_NONE:
+ argc = 0;
+ if (argv[0])
+ *(argv[0]) = '\0';
+ break;
+ case KDB_REPEAT_NO_ARGS:
+ argc = 1;
+ if (argv[1])
+ *(argv[1]) = '\0';
+ break;
+ case KDB_REPEAT_WITH_ARGS:
+ break;
+ }
+ return result;
+ }
+
+ /*
+ * If the input with which we were presented does not
+ * map to an existing command, attempt to parse it as an
+ * address argument and display the result. Useful for
+ * obtaining the address of a variable, or the nearest symbol
+ * to an address contained in a register.
+ */
+ {
+ unsigned long value;
+ char *name = NULL;
+ long offset;
+ int nextarg = 0;
+
+ if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
+ &value, &offset, &name)) {
+ return KDB_NOTFOUND;
+ }
+
+ kdb_printf("%s = ", argv[0]);
+ kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
+ kdb_printf("\n");
+ return 0;
+ }
+}
+
+
+static int handle_ctrl_cmd(char *cmd)
+{
+#define CTRL_P 16
+#define CTRL_N 14
+
+ /* initial situation */
+ if (cmd_head == cmd_tail)
+ return 0;
+ switch (*cmd) {
+ case CTRL_P:
+ if (cmdptr != cmd_tail)
+ cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
+ strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
+ return 1;
+ case CTRL_N:
+ if (cmdptr != cmd_head)
+ cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
+ strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * kdb_reboot - This function implements the 'reboot' command. Reboot
+ * the system immediately, or loop for ever on failure.
+ */
+static int kdb_reboot(int argc, const char **argv)
+{
+ emergency_restart();
+ kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
+ while (1)
+ cpu_relax();
+ /* NOTREACHED */
+ return 0;
+}
+
+static void kdb_dumpregs(struct pt_regs *regs)
+{
+ int old_lvl = console_loglevel;
+ console_loglevel = 15;
+ show_regs(regs);
+ kdb_printf("\n");
+ console_loglevel = old_lvl;
+}
+
+void kdb_set_current_task(struct task_struct *p)
+{
+ kdb_current_task = p;
+
+ if (kdb_task_has_cpu(p)) {
+ struct kdb_running_process *krp = kdb_running_process +
+ kdb_process_cpu(p);
+ kdb_current_regs = krp->regs;
+ return;
+ }
+ kdb_current_regs = NULL;
+}
+
+/*
+ * kdb_local - The main code for kdb. This routine is invoked on a
+ * specific processor, it is not global. The main kdb() routine
+ * ensures that only one processor at a time is in this routine.
+ * This code is called with the real reason code on the first
+ * entry to a kdb session, thereafter it is called with reason
+ * SWITCH, even if the user goes back to the original cpu.
+ * Inputs:
+ * reason The reason KDB was invoked
+ * error The hardware-defined error code
+ * regs The exception frame at time of fault/breakpoint.
+ * db_result Result code from the break or debug point.
+ * Returns:
+ * 0 KDB was invoked for an event which it wasn't responsible
+ * 1 KDB handled the event for which it was invoked.
+ * KDB_CMD_GO User typed 'go'.
+ * KDB_CMD_CPU User switched to another cpu.
+ * KDB_CMD_SS Single step.
+ * KDB_CMD_SSB Single step until branch.
+ */
+static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
+ kdb_dbtrap_t db_result)
+{
+ char *cmdbuf;
+ int diag;
+ struct task_struct *kdb_current =
+ kdb_curr_task(raw_smp_processor_id());
+
+ KDB_DEBUG_STATE("kdb_local 1", reason);
+ kdb_go_count = 0;
+ if (reason == KDB_REASON_DEBUG) {
+ /* special case below */
+ } else {
+ kdb_printf("\nEntering kdb (current=0x%p, pid %d) ",
+ kdb_current, kdb_current->pid);
+#if defined(CONFIG_SMP)
+ kdb_printf("on processor %d ", raw_smp_processor_id());
+#endif
+ }
+
+ switch (reason) {
+ case KDB_REASON_DEBUG:
+ {
+ /*
+ * If re-entering kdb after a single step
+ * command, don't print the message.
+ */
+ switch (db_result) {
+ case KDB_DB_BPT:
+ kdb_printf("\nEntering kdb (0x%p, pid %d) ",
+ kdb_current, kdb_current->pid);
+#if defined(CONFIG_SMP)
+ kdb_printf("on processor %d ", raw_smp_processor_id());
+#endif
+ kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
+ instruction_pointer(regs));
+ break;
+ case KDB_DB_SSB:
+ /*
+ * In the midst of ssb command. Just return.
+ */
+ KDB_DEBUG_STATE("kdb_local 3", reason);
+ return KDB_CMD_SSB; /* Continue with SSB command */
+
+ break;
+ case KDB_DB_SS:
+ break;
+ case KDB_DB_SSBPT:
+ KDB_DEBUG_STATE("kdb_local 4", reason);
+ return 1; /* kdba_db_trap did the work */
+ default:
+ kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
+ db_result);
+ break;
+ }
+
+ }
+ break;
+ case KDB_REASON_ENTER:
+ if (KDB_STATE(KEYBOARD))
+ kdb_printf("due to Keyboard Entry\n");
+ else
+ kdb_printf("due to KDB_ENTER()\n");
+ break;
+ case KDB_REASON_KEYBOARD:
+ KDB_STATE_SET(KEYBOARD);
+ kdb_printf("due to Keyboard Entry\n");
+ break;
+ case KDB_REASON_ENTER_SLAVE:
+ /* drop through, slaves only get released via cpu switch */
+ case KDB_REASON_SWITCH:
+ kdb_printf("due to cpu switch\n");
+ break;
+ case KDB_REASON_OOPS:
+ kdb_printf("Oops: %s\n", kdb_diemsg);
+ kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
+ instruction_pointer(regs));
+ kdb_dumpregs(regs);
+ break;
+ case KDB_REASON_NMI:
+ kdb_printf("due to NonMaskable Interrupt @ "
+ kdb_machreg_fmt "\n",
+ instruction_pointer(regs));
+ kdb_dumpregs(regs);
+ break;
+ case KDB_REASON_SSTEP:
+ case KDB_REASON_BREAK:
+ kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
+ reason == KDB_REASON_BREAK ?
+ "Breakpoint" : "SS trap", instruction_pointer(regs));
+ /*
+ * Determine if this breakpoint is one that we
+ * are interested in.
+ */
+ if (db_result != KDB_DB_BPT) {
+ kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
+ db_result);
+ KDB_DEBUG_STATE("kdb_local 6", reason);
+ return 0; /* Not for us, dismiss it */
+ }
+ break;
+ case KDB_REASON_RECURSE:
+ kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
+ instruction_pointer(regs));
+ break;
+ default:
+ kdb_printf("kdb: unexpected reason code: %d\n", reason);
+ KDB_DEBUG_STATE("kdb_local 8", reason);
+ return 0; /* Not for us, dismiss it */
+ }
+
+ while (1) {
+ /*
+ * Initialize pager context.
+ */
+ kdb_nextline = 1;
+ KDB_STATE_CLEAR(SUPPRESS);
+
+ cmdbuf = cmd_cur;
+ *cmdbuf = '\0';
+ *(cmd_hist[cmd_head]) = '\0';
+
+ if (KDB_FLAG(ONLY_DO_DUMP)) {
+ /* kdb is off but a catastrophic error requires a dump.
+ * Take the dump and reboot.
+ * Turn on logging so the kdb output appears in the log
+ * buffer in the dump.
+ */
+ const char *setargs[] = { "set", "LOGGING", "1" };
+ kdb_set(2, setargs);
+ kdb_reboot(0, NULL);
+ /*NOTREACHED*/
+ }
+
+do_full_getstr:
+#if defined(CONFIG_SMP)
+ snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
+ raw_smp_processor_id());
+#else
+ snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
+#endif
+ if (defcmd_in_progress)
+ strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
+
+ /*
+ * Fetch command from keyboard
+ */
+ cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
+ if (*cmdbuf != '\n') {
+ if (*cmdbuf < 32) {
+ if (cmdptr == cmd_head) {
+ strncpy(cmd_hist[cmd_head], cmd_cur,
+ CMD_BUFLEN);
+ *(cmd_hist[cmd_head] +
+ strlen(cmd_hist[cmd_head])-1) = '\0';
+ }
+ if (!handle_ctrl_cmd(cmdbuf))
+ *(cmd_cur+strlen(cmd_cur)-1) = '\0';
+ cmdbuf = cmd_cur;
+ goto do_full_getstr;
+ } else {
+ strncpy(cmd_hist[cmd_head], cmd_cur,
+ CMD_BUFLEN);
+ }
+
+ cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
+ if (cmd_head == cmd_tail)
+ cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
+ }
+
+ cmdptr = cmd_head;
+ diag = kdb_parse(cmdbuf);
+ if (diag == KDB_NOTFOUND) {
+ kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
+ diag = 0;
+ }
+ if (diag == KDB_CMD_GO
+ || diag == KDB_CMD_CPU
+ || diag == KDB_CMD_SS
+ || diag == KDB_CMD_SSB
+ || diag == KDB_CMD_KGDB)
+ break;
+
+ if (diag)
+ kdb_cmderror(diag);
+ }
+ KDB_DEBUG_STATE("kdb_local 9", diag);
+ return diag;
+}
+
+
+/*
+ * kdb_print_state - Print the state data for the current processor
+ * for debugging.
+ * Inputs:
+ * text Identifies the debug point
+ * value Any integer value to be printed, e.g. reason code.
+ */
+void kdb_print_state(const char *text, int value)
+{
+ kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
+ text, raw_smp_processor_id(), value, kdb_initial_cpu,
+ kdb_state[raw_smp_processor_id()]);
+}
+
+/*
+ * kdb_main_loop - After initial setup and assignment of the
+ * controlling cpu, all cpus are in this loop. One cpu is in
+ * control and will issue the kdb prompt, the others will spin
+ * until 'go' or cpu switch.
+ *
+ * To get a consistent view of the kernel stacks for all
+ * processes, this routine is invoked from the main kdb code via
+ * an architecture specific routine. kdba_main_loop is
+ * responsible for making the kernel stacks consistent for all
+ * processes, there should be no difference between a blocked
+ * process and a running process as far as kdb is concerned.
+ * Inputs:
+ * reason The reason KDB was invoked
+ * error The hardware-defined error code
+ * reason2 kdb's current reason code.
+ * Initially error but can change
+ * acording to kdb state.
+ * db_result Result code from break or debug point.
+ * regs The exception frame at time of fault/breakpoint.
+ * should always be valid.
+ * Returns:
+ * 0 KDB was invoked for an event which it wasn't responsible
+ * 1 KDB handled the event for which it was invoked.
+ */
+int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
+ kdb_dbtrap_t db_result, struct pt_regs *regs)
+{
+ int result = 1;
+ /* Stay in kdb() until 'go', 'ss[b]' or an error */
+ while (1) {
+ /*
+ * All processors except the one that is in control
+ * will spin here.
+ */
+ KDB_DEBUG_STATE("kdb_main_loop 1", reason);
+ while (KDB_STATE(HOLD_CPU)) {
+ /* state KDB is turned off by kdb_cpu to see if the
+ * other cpus are still live, each cpu in this loop
+ * turns it back on.
+ */
+ if (!KDB_STATE(KDB))
+ KDB_STATE_SET(KDB);
+ }
+
+ KDB_STATE_CLEAR(SUPPRESS);
+ KDB_DEBUG_STATE("kdb_main_loop 2", reason);
+ if (KDB_STATE(LEAVING))
+ break; /* Another cpu said 'go' */
+ /* Still using kdb, this processor is in control */
+ result = kdb_local(reason2, error, regs, db_result);
+ KDB_DEBUG_STATE("kdb_main_loop 3", result);
+
+ if (result == KDB_CMD_CPU)
+ break;
+
+ if (result == KDB_CMD_SS) {
+ KDB_STATE_SET(DOING_SS);
+ break;
+ }
+
+ if (result == KDB_CMD_SSB) {
+ KDB_STATE_SET(DOING_SS);
+ KDB_STATE_SET(DOING_SSB);
+ break;
+ }
+
+ if (result == KDB_CMD_KGDB) {
+ if (!(KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)))
+ kdb_printf("Entering please attach debugger "
+ "or use $D#44+ or $3#33\n");
+ break;
+ }
+ if (result && result != 1 && result != KDB_CMD_GO)
+ kdb_printf("\nUnexpected kdb_local return code %d\n",
+ result);
+ KDB_DEBUG_STATE("kdb_main_loop 4", reason);
+ break;
+ }
+ if (KDB_STATE(DOING_SS))
+ KDB_STATE_CLEAR(SSBPT);
+
+ return result;
+}
+
+/*
+ * kdb_mdr - This function implements the guts of the 'mdr', memory
+ * read command.
+ * mdr <addr arg>,<byte count>
+ * Inputs:
+ * addr Start address
+ * count Number of bytes
+ * Returns:
+ * Always 0. Any errors are detected and printed by kdb_getarea.
+ */
+static int kdb_mdr(unsigned long addr, unsigned int count)
+{
+ unsigned char c;
+ while (count--) {
+ if (kdb_getarea(c, addr))
+ return 0;
+ kdb_printf("%02x", c);
+ addr++;
+ }
+ kdb_printf("\n");
+ return 0;
+}
+
+/*
+ * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
+ * 'md8' 'mdr' and 'mds' commands.
+ *
+ * md|mds [<addr arg> [<line count> [<radix>]]]
+ * mdWcN [<addr arg> [<line count> [<radix>]]]
+ * where W = is the width (1, 2, 4 or 8) and N is the count.
+ * for eg., md1c20 reads 20 bytes, 1 at a time.
+ * mdr <addr arg>,<byte count>
+ */
+static void kdb_md_line(const char *fmtstr, unsigned long addr,
+ int symbolic, int nosect, int bytesperword,
+ int num, int repeat, int phys)
+{
+ /* print just one line of data */
+ kdb_symtab_t symtab;
+ char cbuf[32];
+ char *c = cbuf;
+ int i;
+ unsigned long word;
+
+ memset(cbuf, '\0', sizeof(cbuf));
+ if (phys)
+ kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
+ else
+ kdb_printf(kdb_machreg_fmt0 " ", addr);
+
+ for (i = 0; i < num && repeat--; i++) {
+ if (phys) {
+ if (kdb_getphysword(&word, addr, bytesperword))
+ break;
+ } else if (kdb_getword(&word, addr, bytesperword))
+ break;
+ kdb_printf(fmtstr, word);
+ if (symbolic)
+ kdbnearsym(word, &symtab);
+ else
+ memset(&symtab, 0, sizeof(symtab));
+ if (symtab.sym_name) {
+ kdb_symbol_print(word, &symtab, 0);
+ if (!nosect) {
+ kdb_printf("\n");
+ kdb_printf(" %s %s "
+ kdb_machreg_fmt " "
+ kdb_machreg_fmt " "
+ kdb_machreg_fmt, symtab.mod_name,
+ symtab.sec_name, symtab.sec_start,
+ symtab.sym_start, symtab.sym_end);
+ }
+ addr += bytesperword;
+ } else {
+ union {
+ u64 word;
+ unsigned char c[8];
+ } wc;
+ unsigned char *cp;
+#ifdef __BIG_ENDIAN
+ cp = wc.c + 8 - bytesperword;
+#else
+ cp = wc.c;
+#endif
+ wc.word = word;
+#define printable_char(c) \
+ ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
+ switch (bytesperword) {
+ case 8:
+ *c++ = printable_char(*cp++);
+ *c++ = printable_char(*cp++);
+ *c++ = printable_char(*cp++);
+ *c++ = printable_char(*cp++);
+ addr += 4;
+ case 4:
+ *c++ = printable_char(*cp++);
+ *c++ = printable_char(*cp++);
+ addr += 2;
+ case 2:
+ *c++ = printable_char(*cp++);
+ addr++;
+ case 1:
+ *c++ = printable_char(*cp++);
+ addr++;
+ break;
+ }
+#undef printable_char
+ }
+ }
+ kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
+ " ", cbuf);
+}
+
+static int kdb_md(int argc, const char **argv)
+{
+ static unsigned long last_addr;
+ static int last_radix, last_bytesperword, last_repeat;
+ int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
+ int nosect = 0;
+ char fmtchar, fmtstr[64];
+ unsigned long addr;
+ unsigned long word;
+ long offset = 0;
+ int symbolic = 0;
+ int valid = 0;
+ int phys = 0;
+
+ kdbgetintenv("MDCOUNT", &mdcount);
+ kdbgetintenv("RADIX", &radix);
+ kdbgetintenv("BYTESPERWORD", &bytesperword);
+
+ /* Assume 'md <addr>' and start with environment values */
+ repeat = mdcount * 16 / bytesperword;
+
+ if (strcmp(argv[0], "mdr") == 0) {
+ if (argc != 2)
+ return KDB_ARGCOUNT;
+ valid = 1;
+ } else if (isdigit(argv[0][2])) {
+ bytesperword = (int)(argv[0][2] - '0');
+ if (bytesperword == 0) {
+ bytesperword = last_bytesperword;
+ if (bytesperword == 0)
+ bytesperword = 4;
+ }
+ last_bytesperword = bytesperword;
+ repeat = mdcount * 16 / bytesperword;
+ if (!argv[0][3])
+ valid = 1;
+ else if (argv[0][3] == 'c' && argv[0][4]) {
+ char *p;
+ repeat = simple_strtoul(argv[0] + 4, &p, 10);
+ mdcount = ((repeat * bytesperword) + 15) / 16;
+ valid = !*p;
+ }
+ last_repeat = repeat;
+ } else if (strcmp(argv[0], "md") == 0)
+ valid = 1;
+ else if (strcmp(argv[0], "mds") == 0)
+ valid = 1;
+ else if (strcmp(argv[0], "mdp") == 0) {
+ phys = valid = 1;
+ }
+ if (!valid)
+ return KDB_NOTFOUND;
+
+ if (argc == 0) {
+ if (last_addr == 0)
+ return KDB_ARGCOUNT;
+ addr = last_addr;
+ radix = last_radix;
+ bytesperword = last_bytesperword;
+ repeat = last_repeat;
+ mdcount = ((repeat * bytesperword) + 15) / 16;
+ }
+
+ if (argc) {
+ unsigned long val;
+ int diag, nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
+ &offset, NULL);
+ if (diag)
+ return diag;
+ if (argc > nextarg+2)
+ return KDB_ARGCOUNT;
+
+ if (argc >= nextarg) {
+ diag = kdbgetularg(argv[nextarg], &val);
+ if (!diag) {
+ mdcount = (int) val;
+ repeat = mdcount * 16 / bytesperword;
+ }
+ }
+ if (argc >= nextarg+1) {
+ diag = kdbgetularg(argv[nextarg+1], &val);
+ if (!diag)
+ radix = (int) val;
+ }
+ }
+
+ if (strcmp(argv[0], "mdr") == 0)
+ return kdb_mdr(addr, mdcount);
+
+ switch (radix) {
+ case 10:
+ fmtchar = 'd';
+ break;
+ case 16:
+ fmtchar = 'x';
+ break;
+ case 8:
+ fmtchar = 'o';
+ break;
+ default:
+ return KDB_BADRADIX;
+ }
+
+ last_radix = radix;
+
+ if (bytesperword > KDB_WORD_SIZE)
+ return KDB_BADWIDTH;
+
+ switch (bytesperword) {
+ case 8:
+ sprintf(fmtstr, "%%16.16l%c ", fmtchar);
+ break;
+ case 4:
+ sprintf(fmtstr, "%%8.8l%c ", fmtchar);
+ break;
+ case 2:
+ sprintf(fmtstr, "%%4.4l%c ", fmtchar);
+ break;
+ case 1:
+ sprintf(fmtstr, "%%2.2l%c ", fmtchar);
+ break;
+ default:
+ return KDB_BADWIDTH;
+ }
+
+ last_repeat = repeat;
+ last_bytesperword = bytesperword;
+
+ if (strcmp(argv[0], "mds") == 0) {
+ symbolic = 1;
+ /* Do not save these changes as last_*, they are temporary mds
+ * overrides.
+ */
+ bytesperword = KDB_WORD_SIZE;
+ repeat = mdcount;
+ kdbgetintenv("NOSECT", &nosect);
+ }
+
+ /* Round address down modulo BYTESPERWORD */
+
+ addr &= ~(bytesperword-1);
+
+ while (repeat > 0) {
+ unsigned long a;
+ int n, z, num = (symbolic ? 1 : (16 / bytesperword));
+
+ if (KDB_FLAG(CMD_INTERRUPT))
+ return 0;
+ for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
+ if (phys) {
+ if (kdb_getphysword(&word, a, bytesperword)
+ || word)
+ break;
+ } else if (kdb_getword(&word, a, bytesperword) || word)
+ break;
+ }
+ n = min(num, repeat);
+ kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
+ num, repeat, phys);
+ addr += bytesperword * n;
+ repeat -= n;
+ z = (z + num - 1) / num;
+ if (z > 2) {
+ int s = num * (z-2);
+ kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
+ " zero suppressed\n",
+ addr, addr + bytesperword * s - 1);
+ addr += bytesperword * s;
+ repeat -= s;
+ }
+ }
+ last_addr = addr;
+
+ return 0;
+}
+
+/*
+ * kdb_mm - This function implements the 'mm' command.
+ * mm address-expression new-value
+ * Remarks:
+ * mm works on machine words, mmW works on bytes.
+ */
+static int kdb_mm(int argc, const char **argv)
+{
+ int diag;
+ unsigned long addr;
+ long offset = 0;
+ unsigned long contents;
+ int nextarg;
+ int width;
+
+ if (argv[0][2] && !isdigit(argv[0][2]))
+ return KDB_NOTFOUND;
+
+ if (argc < 2)
+ return KDB_ARGCOUNT;
+
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+ if (diag)
+ return diag;
+
+ if (nextarg > argc)
+ return KDB_ARGCOUNT;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
+ if (diag)
+ return diag;
+
+ if (nextarg != argc + 1)
+ return KDB_ARGCOUNT;
+
+ width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
+ diag = kdb_putword(addr, contents, width);
+ if (diag)
+ return diag;
+
+ kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
+
+ return 0;
+}
+
+/*
+ * kdb_go - This function implements the 'go' command.
+ * go [address-expression]
+ */
+static int kdb_go(int argc, const char **argv)
+{
+ unsigned long addr;
+ int diag;
+ int nextarg;
+ long offset;
+
+ if (argc == 1) {
+ if (raw_smp_processor_id() != kdb_initial_cpu) {
+ kdb_printf("go <address> must be issued from the "
+ "initial cpu, do cpu %d first\n",
+ kdb_initial_cpu);
+ return KDB_ARGCOUNT;
+ }
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg,
+ &addr, &offset, NULL);
+ if (diag)
+ return diag;
+ } else if (argc) {
+ return KDB_ARGCOUNT;
+ }
+
+ diag = KDB_CMD_GO;
+ if (KDB_FLAG(CATASTROPHIC)) {
+ kdb_printf("Catastrophic error detected\n");
+ kdb_printf("kdb_continue_catastrophic=%d, ",
+ kdb_continue_catastrophic);
+ if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
+ kdb_printf("type go a second time if you really want "
+ "to continue\n");
+ return 0;
+ }
+ if (kdb_continue_catastrophic == 2) {
+ kdb_printf("forcing reboot\n");
+ kdb_reboot(0, NULL);
+ }
+ kdb_printf("attempting to continue\n");
+ }
+ if (raw_smp_processor_id() != kdb_initial_cpu) {
+ char buf[80];
+ kdb_printf("go was not issued from initial cpu, switching "
+ "back to cpu %d\n", kdb_initial_cpu);
+ sprintf(buf, "cpu %d\n", kdb_initial_cpu);
+ /* Recursive use of kdb_parse, do not use argv after
+ * this point */
+ argv = NULL;
+ diag = kdb_parse(buf);
+ if (diag == KDB_CMD_CPU)
+ KDB_STATE_SET_CPU(GO_SWITCH, kdb_initial_cpu);
+ }
+ return diag;
+}
+
+/*
+ * kdb_rd - This function implements the 'rd' command.
+ */
+static int kdb_rd(int argc, const char **argv)
+{
+ int diag = kdb_check_regs();
+ if (diag)
+ return diag;
+
+ kdb_dumpregs(kdb_current_regs);
+ return 0;
+}
+
+/*
+ * kdb_rm - This function implements the 'rm' (register modify) command.
+ * rm register-name new-contents
+ * Remarks:
+ * Currently doesn't allow modification of control or
+ * debug registers.
+ */
+static int kdb_rm(int argc, const char **argv)
+{
+ int diag;
+ int ind = 0;
+ unsigned long contents;
+
+ if (argc != 2)
+ return KDB_ARGCOUNT;
+ /*
+ * Allow presence or absence of leading '%' symbol.
+ */
+ if (argv[1][0] == '%')
+ ind = 1;
+
+ diag = kdbgetularg(argv[2], &contents);
+ if (diag)
+ return diag;
+
+ diag = kdb_check_regs();
+ if (diag)
+ return diag;
+ kdb_printf("ERROR: Register set currently not implemented\n");
+ return 0;
+}
+
+#if defined(CONFIG_MAGIC_SYSRQ)
+/*
+ * kdb_sr - This function implements the 'sr' (SYSRQ key) command
+ * which interfaces to the soi-disant MAGIC SYSRQ functionality.
+ * sr <magic-sysrq-code>
+ */
+static int kdb_sr(int argc, const char **argv)
+{
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+ if (!__sysrq_enabled) {
+ kdb_printf("Auto activating sysrq\n");
+ __sysrq_enabled = 1;
+ }
+
+ handle_sysrq(*argv[1], NULL);
+
+ return 0;
+}
+#endif /* CONFIG_MAGIC_SYSRQ */
+
+/*
+ * kdb_ef - This function implements the 'regs' (display exception
+ * frame) command. This command takes an address and expects to
+ * find an exception frame at that address, formats and prints
+ * it.
+ * regs address-expression
+ * Remarks:
+ * Not done yet.
+ */
+static int kdb_ef(int argc, const char **argv)
+{
+ int diag;
+ unsigned long addr;
+ long offset;
+ int nextarg;
+
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+ if (diag)
+ return diag;
+ show_regs((struct pt_regs *)addr);
+ return 0;
+}
+
+#if defined(CONFIG_MODULES)
+/* modules using other modules */
+struct module_use {
+ struct list_head list;
+ struct module *module_which_uses;
+};
+
+/*
+ * kdb_lsmod - This function implements the 'lsmod' command. Lists
+ * currently loaded kernel modules.
+ * Mostly taken from userland lsmod.
+ */
+static int kdb_lsmod(int argc, const char **argv)
+{
+ struct module *mod;
+
+ if (argc != 0)
+ return KDB_ARGCOUNT;
+
+ kdb_printf("Module Size modstruct Used by\n");
+ list_for_each_entry(mod, kdb_modules, list) {
+
+ kdb_printf("%-20s%8u 0x%p ", mod->name,
+ mod->core_size, (void *)mod);
+#ifdef CONFIG_MODULE_UNLOAD
+ kdb_printf("%4d ", module_refcount(mod));
+#endif
+ if (mod->state == MODULE_STATE_GOING)
+ kdb_printf(" (Unloading)");
+ else if (mod->state == MODULE_STATE_COMING)
+ kdb_printf(" (Loading)");
+ else
+ kdb_printf(" (Live)");
+
+#ifdef CONFIG_MODULE_UNLOAD
+ {
+ struct module_use *use;
+ kdb_printf(" [ ");
+ list_for_each_entry(use, &mod->modules_which_use_me,
+ list)
+ kdb_printf("%s ", use->module_which_uses->name);
+ kdb_printf("]\n");
+ }
+#endif
+ }
+
+ return 0;
+}
+
+#endif /* CONFIG_MODULES */
+
+/*
+ * kdb_env - This function implements the 'env' command. Display the
+ * current environment variables.
+ */
+
+static int kdb_env(int argc, const char **argv)
+{
+ int i;
+
+ for (i = 0; i < __nenv; i++) {
+ if (__env[i])
+ kdb_printf("%s\n", __env[i]);
+ }
+
+ if (KDB_DEBUG(MASK))
+ kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
+
+ return 0;
+}
+
+#ifdef CONFIG_PRINTK
+/*
+ * kdb_dmesg - This function implements the 'dmesg' command to display
+ * the contents of the syslog buffer.
+ * dmesg [lines] [adjust]
+ */
+static int kdb_dmesg(int argc, const char **argv)
+{
+ char *syslog_data[4], *start, *end, c = '\0', *p;
+ int diag, logging, logsize, lines = 0, adjust = 0, n;
+
+ if (argc > 2)
+ return KDB_ARGCOUNT;
+ if (argc) {
+ char *cp;
+ lines = simple_strtol(argv[1], &cp, 0);
+ if (*cp)
+ lines = 0;
+ if (argc > 1) {
+ adjust = simple_strtoul(argv[2], &cp, 0);
+ if (*cp || adjust < 0)
+ adjust = 0;
+ }
+ }
+
+ /* disable LOGGING if set */
+ diag = kdbgetintenv("LOGGING", &logging);
+ if (!diag && logging) {
+ const char *setargs[] = { "set", "LOGGING", "0" };
+ kdb_set(2, setargs);
+ }
+
+ /* syslog_data[0,1] physical start, end+1. syslog_data[2,3]
+ * logical start, end+1. */
+ kdb_syslog_data(syslog_data);
+ if (syslog_data[2] == syslog_data[3])
+ return 0;
+ logsize = syslog_data[1] - syslog_data[0];
+ start = syslog_data[2];
+ end = syslog_data[3];
+#define KDB_WRAP(p) (((p - syslog_data[0]) % logsize) + syslog_data[0])
+ for (n = 0, p = start; p < end; ++p) {
+ c = *KDB_WRAP(p);
+ if (c == '\n')
+ ++n;
+ }
+ if (c != '\n')
+ ++n;
+ if (lines < 0) {
+ if (adjust >= n)
+ kdb_printf("buffer only contains %d lines, nothing "
+ "printed\n", n);
+ else if (adjust - lines >= n)
+ kdb_printf("buffer only contains %d lines, last %d "
+ "lines printed\n", n, n - adjust);
+ if (adjust) {
+ for (; start < end && adjust; ++start) {
+ if (*KDB_WRAP(start) == '\n')
+ --adjust;
+ }
+ if (start < end)
+ ++start;
+ }
+ for (p = start; p < end && lines; ++p) {
+ if (*KDB_WRAP(p) == '\n')
+ ++lines;
+ }
+ end = p;
+ } else if (lines > 0) {
+ int skip = n - (adjust + lines);
+ if (adjust >= n) {
+ kdb_printf("buffer only contains %d lines, "
+ "nothing printed\n", n);
+ skip = n;
+ } else if (skip < 0) {
+ lines += skip;
+ skip = 0;
+ kdb_printf("buffer only contains %d lines, first "
+ "%d lines printed\n", n, lines);
+ }
+ for (; start < end && skip; ++start) {
+ if (*KDB_WRAP(start) == '\n')
+ --skip;
+ }
+ for (p = start; p < end && lines; ++p) {
+ if (*KDB_WRAP(p) == '\n')
+ --lines;
+ }
+ end = p;
+ }
+ /* Do a line at a time (max 200 chars) to reduce protocol overhead */
+ c = '\n';
+ while (start != end) {
+ char buf[201];
+ p = buf;
+ if (KDB_FLAG(CMD_INTERRUPT))
+ return 0;
+ while (start < end && (c = *KDB_WRAP(start)) &&
+ (p - buf) < sizeof(buf)-1) {
+ ++start;
+ *p++ = c;
+ if (c == '\n')
+ break;
+ }
+ *p = '\0';
+ kdb_printf("%s", buf);
+ }
+ if (c != '\n')
+ kdb_printf("\n");
+
+ return 0;
+}
+#endif /* CONFIG_PRINTK */
+/*
+ * kdb_cpu - This function implements the 'cpu' command.
+ * cpu [<cpunum>]
+ * Returns:
+ * KDB_CMD_CPU for success, a kdb diagnostic if error
+ */
+static void kdb_cpu_status(void)
+{
+ int i, start_cpu, first_print = 1;
+ char state, prev_state = '?';
+
+ kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
+ kdb_printf("Available cpus: ");
+ for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
+ if (!cpu_online(i)) {
+ state = 'F'; /* cpu is offline */
+ } else {
+ struct kdb_running_process *krp =
+ kdb_running_process + i;
+ state = ' '; /* cpu is responding to kdb */
+ if (kdb_task_state_char(krp->p) == 'I')
+ state = 'I'; /* idle task */
+ }
+ if (state != prev_state) {
+ if (prev_state != '?') {
+ if (!first_print)
+ kdb_printf(", ");
+ first_print = 0;
+ kdb_printf("%d", start_cpu);
+ if (start_cpu < i-1)
+ kdb_printf("-%d", i-1);
+ if (prev_state != ' ')
+ kdb_printf("(%c)", prev_state);
+ }
+ prev_state = state;
+ start_cpu = i;
+ }
+ }
+ /* print the trailing cpus, ignoring them if they are all offline */
+ if (prev_state != 'F') {
+ if (!first_print)
+ kdb_printf(", ");
+ kdb_printf("%d", start_cpu);
+ if (start_cpu < i-1)
+ kdb_printf("-%d", i-1);
+ if (prev_state != ' ')
+ kdb_printf("(%c)", prev_state);
+ }
+ kdb_printf("\n");
+}
+
+static int kdb_cpu(int argc, const char **argv)
+{
+ unsigned long cpunum;
+ int diag;
+
+ if (argc == 0) {
+ kdb_cpu_status();
+ return 0;
+ }
+
+ if (argc != 1)
+ return KDB_ARGCOUNT;
+
+ diag = kdbgetularg(argv[1], &cpunum);
+ if (diag)
+ return diag;
+
+ /*
+ * Validate cpunum
+ */
+ if ((cpunum > NR_CPUS) || !cpu_online(cpunum))
+ return KDB_BADCPUNUM;
+
+ dbg_switch_cpu = cpunum;
+
+ /*
+ * Switch to other cpu
+ */
+ return KDB_CMD_CPU;
+}
+
+/* The user may not realize that ps/bta with no parameters does not print idle
+ * or sleeping system daemon processes, so tell them how many were suppressed.
+ */
+void kdb_ps_suppressed(void)
+{
+ int idle = 0, daemon = 0;
+ unsigned long mask_I = kdb_task_state_string("I"),
+ mask_M = kdb_task_state_string("M");
+ unsigned long cpu;
+ const struct task_struct *p, *g;
+ for_each_online_cpu(cpu) {
+ p = kdb_curr_task(cpu);
+ if (kdb_task_state(p, mask_I))
+ ++idle;
+ }
+ kdb_do_each_thread(g, p) {
+ if (kdb_task_state(p, mask_M))
+ ++daemon;
+ } kdb_while_each_thread(g, p);
+ if (idle || daemon) {
+ if (idle)
+ kdb_printf("%d idle process%s (state I)%s\n",
+ idle, idle == 1 ? "" : "es",
+ daemon ? " and " : "");
+ if (daemon)
+ kdb_printf("%d sleeping system daemon (state M) "
+ "process%s", daemon,
+ daemon == 1 ? "" : "es");
+ kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
+ }
+}
+
+/*
+ * kdb_ps - This function implements the 'ps' command which shows a
+ * list of the active processes.
+ * ps [DRSTCZEUIMA] All processes, optionally filtered by state
+ */
+void kdb_ps1(const struct task_struct *p)
+{
+ struct kdb_running_process *krp = kdb_running_process +
+ kdb_process_cpu(p);
+ kdb_printf("0x%p %8d %8d %d %4d %c 0x%p %c%s\n",
+ (void *)p, p->pid, p->parent->pid,
+ kdb_task_has_cpu(p), kdb_process_cpu(p),
+ kdb_task_state_char(p),
+ (void *)(&p->thread),
+ p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
+ p->comm);
+ if (kdb_task_has_cpu(p)) {
+ if (!krp->seqno || !krp->p)
+ kdb_printf(" Error: no saved data for this cpu\n");
+ else {
+ if (krp->seqno < kdb_seqno - 1)
+ kdb_printf(" Warning: process state is "
+ "stale\n");
+ if (krp->p != p)
+ kdb_printf(" Error: does not match running "
+ "process table (0x%p)\n", krp->p);
+ }
+ }
+}
+
+static int kdb_ps(int argc, const char **argv)
+{
+ struct task_struct *g, *p;
+ unsigned long mask, cpu;
+
+ if (argc == 0)
+ kdb_ps_suppressed();
+ kdb_printf("%-*s Pid Parent [*] cpu State %-*s Command\n",
+ (int)(2*sizeof(void *))+2, "Task Addr",
+ (int)(2*sizeof(void *))+2, "Thread");
+ mask = kdb_task_state_string(argc ? argv[1] : NULL);
+ /* Run the active tasks first */
+ for_each_online_cpu(cpu) {
+ if (KDB_FLAG(CMD_INTERRUPT))
+ return 0;
+ p = kdb_curr_task(cpu);
+ if (kdb_task_state(p, mask))
+ kdb_ps1(p);
+ }
+ kdb_printf("\n");
+ /* Now the real tasks */
+ kdb_do_each_thread(g, p) {
+ if (KDB_FLAG(CMD_INTERRUPT))
+ return 0;
+ if (kdb_task_state(p, mask))
+ kdb_ps1(p);
+ } kdb_while_each_thread(g, p);
+
+ return 0;
+}
+
+/*
+ * kdb_pid - This function implements the 'pid' command which switches
+ * the currently active process.
+ * pid [<pid> | R]
+ */
+static int kdb_pid(int argc, const char **argv)
+{
+ struct task_struct *p;
+ unsigned long val;
+ int diag;
+
+ if (argc > 1)
+ return KDB_ARGCOUNT;
+
+ if (argc) {
+ if (strcmp(argv[1], "R") == 0) {
+ p = KDB_RUNNING_PROCESS_ORIGINAL[kdb_initial_cpu].p;
+ } else {
+ diag = kdbgetularg(argv[1], &val);
+ if (diag)
+ return KDB_BADINT;
+
+ p = find_task_by_pid_ns((pid_t)val, &init_pid_ns);
+ if (!p) {
+ kdb_printf("No task with pid=%d\n", (pid_t)val);
+ return 0;
+ }
+ }
+ kdb_set_current_task(p);
+ }
+ kdb_printf("KDB current process is %s(pid=%d)\n",
+ kdb_current_task->comm,
+ kdb_current_task->pid);
+
+ return 0;
+}
+
+/*
+ * kdb_ll - This function implements the 'll' command which follows a
+ * linked list and executes an arbitrary command for each
+ * element.
+ */
+static int kdb_ll(int argc, const char **argv)
+{
+ int diag;
+ unsigned long addr;
+ long offset = 0;
+ unsigned long va;
+ unsigned long linkoffset;
+ int nextarg;
+ const char *command;
+
+ if (argc != 3)
+ return KDB_ARGCOUNT;
+
+ nextarg = 1;
+ diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
+ if (diag)
+ return diag;
+
+ diag = kdbgetularg(argv[2], &linkoffset);
+ if (diag)
+ return diag;
+
+ /*
+ * Using the starting address as
+ * the first element in the list, and assuming that
+ * the list ends with a null pointer.
+ */
+
+ va = addr;
+ command = kdb_strdup(argv[3], GFP_KDB);
+ if (!command) {
+ kdb_printf("%s: cannot duplicate command\n", __func__);
+ return 0;
+ }
+ /* Recursive use of kdb_parse, do not use argv after this point */
+ argv = NULL;
+
+ while (va) {
+ char buf[80];
+
+ sprintf(buf, "%s " kdb_machreg_fmt "\n", command, va);
+ diag = kdb_parse(buf);
+ if (diag)
+ return diag;
+
+ addr = va + linkoffset;
+ if (kdb_getword(&va, addr, sizeof(va)))
+ return 0;
+ }
+ kfree(command);
+
+ return 0;
+}
+
+static int kdb_kgdb(int argc, const char **argv)
+{
+ return KDB_CMD_KGDB;
+}
+
+/*
+ * kdb_help - This function implements the 'help' and '?' commands.
+ */
+static int kdb_help(int argc, const char **argv)
+{
+ kdbtab_t *kt;
+ int i;
+
+ kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
+ kdb_printf("-----------------------------"
+ "-----------------------------\n");
+ for (i = 0, kt = kdb_commands; i < kdb_max_commands; i++, kt++) {
+ if (kt->cmd_name)
+ kdb_printf("%-15.15s %-20.20s %s\n", kt->cmd_name,
+ kt->cmd_usage, kt->cmd_help);
+ }
+ return 0;
+}
+
+/*
+ * kdb_kill - This function implements the 'kill' commands.
+ */
+static int kdb_kill(int argc, const char **argv)
+{
+ long sig, pid;
+ char *endp;
+ struct task_struct *p;
+ struct siginfo info;
+
+ if (argc != 2)
+ return KDB_ARGCOUNT;
+
+ sig = simple_strtol(argv[1], &endp, 0);
+ if (*endp)
+ return KDB_BADINT;
+ if (sig >= 0) {
+ kdb_printf("Invalid signal parameter.<-signal>\n");
+ return 0;
+ }
+ sig = -sig;
+
+ pid = simple_strtol(argv[2], &endp, 0);
+ if (*endp)
+ return KDB_BADINT;
+ if (pid <= 0) {
+ kdb_printf("Process ID must be large than 0.\n");
+ return 0;
+ }
+
+ /* Find the process. */
+ p = find_task_by_pid_ns(pid, &init_pid_ns);
+ if (!p) {
+ kdb_printf("The specified process isn't found.\n");
+ return 0;
+ }
+ p = p->group_leader;
+ info.si_signo = sig;
+ info.si_errno = 0;
+ info.si_code = SI_USER;
+ info.si_pid = pid; /* same capabilities as process being signalled */
+ info.si_uid = 0; /* kdb has root authority */
+ kdb_send_sig_info(p, &info, kdb_seqno);
+ return 0;
+}
+
+struct kdb_tm {
+ int tm_sec; /* seconds */
+ int tm_min; /* minutes */
+ int tm_hour; /* hours */
+ int tm_mday; /* day of the month */
+ int tm_mon; /* month */
+ int tm_year; /* year */
+};
+
+static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm)
+{
+ /* This will work from 1970-2099, 2100 is not a leap year */
+ static int mon_day[] = { 31, 29, 31, 30, 31, 30, 31,
+ 31, 30, 31, 30, 31 };
+ memset(tm, 0, sizeof(*tm));
+ tm->tm_sec = tv->tv_sec % (24 * 60 * 60);
+ tm->tm_mday = tv->tv_sec / (24 * 60 * 60) +
+ (2 * 365 + 1); /* shift base from 1970 to 1968 */
+ tm->tm_min = tm->tm_sec / 60 % 60;
+ tm->tm_hour = tm->tm_sec / 60 / 60;
+ tm->tm_sec = tm->tm_sec % 60;
+ tm->tm_year = 68 + 4*(tm->tm_mday / (4*365+1));
+ tm->tm_mday %= (4*365+1);
+ mon_day[1] = 29;
+ while (tm->tm_mday >= mon_day[tm->tm_mon]) {
+ tm->tm_mday -= mon_day[tm->tm_mon];
+ if (++tm->tm_mon == 12) {
+ tm->tm_mon = 0;
+ ++tm->tm_year;
+ mon_day[1] = 28;
+ }
+ }
+ ++tm->tm_mday;
+}
+
+/*
+ * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
+ * I cannot call that code directly from kdb, it has an unconditional
+ * cli()/sti() and calls routines that take locks which can stop the debugger.
+ */
+static void kdb_sysinfo(struct sysinfo *val)
+{
+ struct timespec uptime;
+ do_posix_clock_monotonic_gettime(&uptime);
+ memset(val, 0, sizeof(*val));
+ val->uptime = uptime.tv_sec;
+ val->loads[0] = avenrun[0];
+ val->loads[1] = avenrun[1];
+ val->loads[2] = avenrun[2];
+ val->procs = nr_threads-1;
+ si_meminfo(val);
+ __si_swapinfo(val);
+
+ return;
+}
+
+/*
+ * kdb_summary - This function implements the 'summary' command.
+ */
+static int kdb_summary(int argc, const char **argv)
+{
+ struct kdb_tm tm;
+ struct sysinfo val;
+
+ if (argc)
+ return KDB_ARGCOUNT;
+
+ kdb_printf("sysname %s\n", init_uts_ns.name.sysname);
+ kdb_printf("release %s\n", init_uts_ns.name.release);
+ kdb_printf("version %s\n", init_uts_ns.name.version);
+ kdb_printf("machine %s\n", init_uts_ns.name.machine);
+ kdb_printf("nodename %s\n", init_uts_ns.name.nodename);
+ kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
+ kdb_printf("ccversion %s\n", __stringify(CCVERSION));
+
+ kdb_gmtime(&xtime, &tm);
+ kdb_printf("date %04d-%02d-%02d %02d:%02d:%02d "
+ "tz_minuteswest %d\n",
+ 1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
+ tm.tm_hour, tm.tm_min, tm.tm_sec,
+ sys_tz.tz_minuteswest);
+
+ kdb_sysinfo(&val);
+ kdb_printf("uptime ");
+ if (val.uptime > (24*60*60)) {
+ int days = val.uptime / (24*60*60);
+ val.uptime %= (24*60*60);
+ kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
+ }
+ kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
+
+ /* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */
+
+#define LOAD_INT(x) ((x) >> FSHIFT)
+#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
+ kdb_printf("load avg %ld.%02ld %ld.%02ld %ld.%02ld\n",
+ LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
+ LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
+ LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
+ kdb_printf("\n");
+#undef LOAD_INT
+#undef LOAD_FRAC
+
+ kdb_seq_file_reset();
+ _meminfo_proc_show(&kdb_seq_file, NULL, 0); /* in fs/proc/meminfo.c */
+ kdb_seq_file_print();
+
+ return 0;
+}
+
+/*
+ * kdb_per_cpu - This function implements the 'per_cpu' command.
+ */
+static int kdb_per_cpu(int argc, const char **argv)
+{
+ char buf[256], fmtstr[64];
+ kdb_symtab_t symtab;
+ cpumask_t suppress = CPU_MASK_NONE;
+ int cpu, diag;
+ unsigned long addr, val, bytesperword = 0, whichcpu = ~0UL;
+
+ if (argc < 1 || argc > 3)
+ return KDB_ARGCOUNT;
+
+ snprintf(buf, sizeof(buf), "per_cpu__%s", argv[1]);
+ if (!kdbgetsymval(buf, &symtab)) {
+ kdb_printf("%s is not a per_cpu variable\n", argv[1]);
+ return KDB_BADADDR;
+ }
+ if (argc >= 2) {
+ diag = kdbgetularg(argv[2], &bytesperword);
+ if (diag)
+ return diag;
+ }
+ if (!bytesperword)
+ bytesperword = KDB_WORD_SIZE;
+ else if (bytesperword > KDB_WORD_SIZE)
+ return KDB_BADWIDTH;
+ sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
+ if (argc >= 3) {
+ diag = kdbgetularg(argv[3], &whichcpu);
+ if (diag)
+ return diag;
+ if (!cpu_online(whichcpu)) {
+ kdb_printf("cpu %ld is not online\n", whichcpu);
+ return KDB_BADCPUNUM;
+ }
+ }
+
+ /* Most architectures use __per_cpu_offset[cpu], some use
+ * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
+ */
+#ifdef __per_cpu_offset
+#define KDB_PCU(cpu) __per_cpu_offset(cpu)
+#else
+#ifdef CONFIG_SMP
+#define KDB_PCU(cpu) __per_cpu_offset[cpu]
+#else
+#define KDB_PCU(cpu) 0
+#endif
+#endif
+
+ for_each_online_cpu(cpu) {
+ if (whichcpu != ~0UL && whichcpu != cpu)
+ continue;
+ addr = symtab.sym_start + KDB_PCU(cpu);
+ diag = kdb_getword(&val, addr, bytesperword);
+ if (diag) {
+ kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
+ "read, diag=%d\n", cpu, addr, diag);
+ continue;
+ }
+#ifdef CONFIG_SMP
+ if (!val) {
+ cpu_set(cpu, suppress);
+ continue;
+ }
+#endif /* CONFIG_SMP */
+ kdb_printf("%5d ", cpu);
+ kdb_md_line(fmtstr, addr,
+ bytesperword == KDB_WORD_SIZE,
+ 1, bytesperword, 1, 1, 0);
+ }
+ if (cpus_weight(suppress) == 0)
+ return 0;
+ kdb_printf("Zero suppressed cpu(s):");
+ for (cpu = first_cpu(suppress); cpu < num_possible_cpus();
+ cpu = next_cpu(cpu, suppress)) {
+ kdb_printf(" %d", cpu);
+ if (cpu == num_possible_cpus() - 1 ||
+ next_cpu(cpu, suppress) != cpu + 1)
+ continue;
+ while (cpu < num_possible_cpus() &&
+ next_cpu(cpu, suppress) == cpu + 1)
+ ++cpu;
+ kdb_printf("-%d", cpu);
+ }
+ kdb_printf("\n");
+
+#undef KDB_PCU
+
+ return 0;
+}
+
+/*
+ * display help for the use of cmd | grep pattern
+ */
+static int kdb_grep_help(int argc, const char **argv)
+{
+ kdb_printf("Usage of cmd args | grep pattern:\n");
+ kdb_printf(" Any command's output may be filtered through an ");
+ kdb_printf("emulated 'pipe'.\n");
+ kdb_printf(" 'grep' is just a key word.\n");
+ kdb_printf(" The pattern may include a very limited set of "
+ "metacharacters:\n");
+ kdb_printf(" pattern or ^pattern or pattern$ or ^pattern$\n");
+ kdb_printf(" And if there are spaces in the pattern, you may "
+ "quote it:\n");
+ kdb_printf(" \"pat tern\" or \"^pat tern\" or \"pat tern$\""
+ " or \"^pat tern$\"\n");
+ return 0;
+}
+
+/*
+ * kdb_register_repeat - This function is used to register a kernel
+ * debugger command.
+ * Inputs:
+ * cmd Command name
+ * func Function to execute the command
+ * usage A simple usage string showing arguments
+ * help A simple help string describing command
+ * repeat Does the command auto repeat on enter?
+ * Returns:
+ * zero for success, one if a duplicate command.
+ */
+#define kdb_command_extend 50 /* arbitrary */
+int kdb_register_repeat(char *cmd,
+ kdb_func_t func,
+ char *usage,
+ char *help,
+ short minlen,
+ kdb_repeat_t repeat)
+{
+ int i;
+ kdbtab_t *kp;
+
+ /*
+ * Brute force method to determine duplicates
+ */
+ for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++) {
+ if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
+ kdb_printf("Duplicate kdb command registered: "
+ "%s, func %p help %s\n", cmd, func, help);
+ return 1;
+ }
+ }
+
+ /*
+ * Insert command into first available location in table
+ */
+ for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++) {
+ if (kp->cmd_name == NULL)
+ break;
+ }
+
+ if (i >= kdb_max_commands) {
+ kdbtab_t *new = kmalloc((kdb_max_commands +
+ kdb_command_extend) * sizeof(*new), GFP_KDB);
+ if (!new) {
+ kdb_printf("Could not allocate new kdb_command "
+ "table\n");
+ return 1;
+ }
+ if (kdb_commands) {
+ memcpy(new, kdb_commands,
+ kdb_max_commands * sizeof(*new));
+ kfree(kdb_commands);
+ }
+ memset(new + kdb_max_commands, 0,
+ kdb_command_extend * sizeof(*new));
+ kdb_commands = new;
+ kp = kdb_commands + kdb_max_commands;
+ kdb_max_commands += kdb_command_extend;
+ }
+
+ kp->cmd_name = cmd;
+ kp->cmd_func = func;
+ kp->cmd_usage = usage;
+ kp->cmd_help = help;
+ kp->cmd_flags = 0;
+ kp->cmd_minlen = minlen;
+ kp->cmd_repeat = repeat;
+
+ return 0;
+}
+
+/*
+ * kdb_register - Compatibility register function for commands that do
+ * not need to specify a repeat state. Equivalent to
+ * kdb_register_repeat with KDB_REPEAT_NONE.
+ * Inputs:
+ * cmd Command name
+ * func Function to execute the command
+ * usage A simple usage string showing arguments
+ * help A simple help string describing command
+ * Returns:
+ * zero for success, one if a duplicate command.
+ */
+int kdb_register(char *cmd,
+ kdb_func_t func,
+ char *usage,
+ char *help,
+ short minlen)
+{
+ return kdb_register_repeat(cmd, func, usage, help, minlen,
+ KDB_REPEAT_NONE);
+}
+
+/*
+ * kdb_unregister - This function is used to unregister a kernel
+ * debugger command. It is generally called when a module which
+ * implements kdb commands is unloaded.
+ * Inputs:
+ * cmd Command name
+ * Returns:
+ * zero for success, one command not registered.
+ */
+int kdb_unregister(char *cmd)
+{
+ int i;
+ kdbtab_t *kp;
+
+ /*
+ * find the command.
+ */
+ for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++) {
+ if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
+ kp->cmd_name = NULL;
+ return 0;
+ }
+ }
+
+ /* Couldn't find it. */
+ return 1;
+}
+
+/* Initialize the kdb command table. */
+static void __init kdb_inittab(void)
+{
+ int i;
+ kdbtab_t *kp;
+
+ for (i = 0, kp = kdb_commands; i < kdb_max_commands; i++, kp++)
+ kp->cmd_name = NULL;
+
+ kdb_register_repeat("md", kdb_md, "<vaddr>",
+ "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
+ KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("mdr", kdb_md, "<vaddr> <bytes>",
+ "Display Raw Memory", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("mdp", kdb_md, "<paddr> <bytes>",
+ "Display Physical Memory", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("mds", kdb_md, "<vaddr>",
+ "Display Memory Symbolically", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("mm", kdb_mm, "<vaddr> <contents>",
+ "Modify Memory Contents", 0, KDB_REPEAT_NO_ARGS);
+ kdb_register_repeat("go", kdb_go, "[<vaddr>]",
+ "Continue Execution", 1, KDB_REPEAT_NONE);
+ kdb_register_repeat("rd", kdb_rd, "",
+ "Display Registers", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("rm", kdb_rm, "<reg> <contents>",
+ "Modify Registers", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("ef", kdb_ef, "<vaddr>",
+ "Display exception frame", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("bt", kdb_bt, "[<vaddr>]",
+ "Stack traceback", 1, KDB_REPEAT_NONE);
+ kdb_register_repeat("btp", kdb_bt, "<pid>",
+ "Display stack for process <pid>", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("bta", kdb_bt, "[DRSTCZEUIMA]",
+ "Display stack all processes", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("btc", kdb_bt, "",
+ "Backtrace current process on each cpu", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("btt", kdb_bt, "<vaddr>",
+ "Backtrace process given its struct task address", 0,
+ KDB_REPEAT_NONE);
+ kdb_register_repeat("ll", kdb_ll, "<first-element> <linkoffset> <cmd>",
+ "Execute cmd for each element in linked list", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("env", kdb_env, "",
+ "Show environment variables", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("set", kdb_set, "",
+ "Set environment variables", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("help", kdb_help, "",
+ "Display Help Message", 1, KDB_REPEAT_NONE);
+ kdb_register_repeat("?", kdb_help, "",
+ "Display Help Message", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("cpu", kdb_cpu, "<cpunum>",
+ "Switch to new cpu", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("kgdb", kdb_kgdb, "",
+ "Enter kgdb mode", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("ps", kdb_ps, "[<flags>|A]",
+ "Display active task list", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("pid", kdb_pid, "<pidnum>",
+ "Switch to another task", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("reboot", kdb_reboot, "",
+ "Reboot the machine immediately", 0, KDB_REPEAT_NONE);
+#if defined(CONFIG_MODULES)
+ kdb_register_repeat("lsmod", kdb_lsmod, "",
+ "List loaded kernel modules", 0, KDB_REPEAT_NONE);
+#endif
+#if defined(CONFIG_MAGIC_SYSRQ)
+ kdb_register_repeat("sr", kdb_sr, "<key>",
+ "Magic SysRq key", 0, KDB_REPEAT_NONE);
+#endif
+#if defined(CONFIG_PRINTK)
+ kdb_register_repeat("dmesg", kdb_dmesg, "[lines]",
+ "Display syslog buffer", 0, KDB_REPEAT_NONE);
+#endif
+ kdb_register_repeat("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
+ "Define a set of commands, down to endefcmd", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("kill", kdb_kill, "<-signal> <pid>",
+ "Send a signal to a process", 0, KDB_REPEAT_NONE);
+ kdb_register_repeat("summary", kdb_summary, "",
+ "Summarize the system", 4, KDB_REPEAT_NONE);
+ kdb_register_repeat("per_cpu", kdb_per_cpu, "",
+ "Display per_cpu variables", 3, KDB_REPEAT_NONE);
+ kdb_register_repeat("grephelp", kdb_grep_help, "",
+ "Display help on | grep", 0, KDB_REPEAT_NONE);
+}
+
+/* Execute any commands defined in kdb_cmds. */
+static void __init kdb_cmd_init(void)
+{
+ int i, diag;
+ for (i = 0; kdb_cmds[i]; ++i) {
+ diag = kdb_parse(kdb_cmds[i]);
+ if (diag)
+ kdb_printf("kdb command %s failed, kdb diag %d\n",
+ kdb_cmds[i], diag);
+ }
+ if (defcmd_in_progress) {
+ kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
+ kdb_parse("endefcmd");
+ }
+}
+
+/* Intialize kdb_printf, breakpoint tables and kdb state */
+void __init kdb_init(void)
+{
+ kdb_inittab(); /* Initialize Command Table */
+ kdb_initbptab(); /* Initialize Breakpoint Table */
+ kdb_cmd_init(); /* Preset commands from kdb_cmds */
+ kdb_initial_cpu = -1; /* Avoid recursion problems */
+}
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
new file mode 100644
index 0000000..768655e
--- /dev/null
+++ b/kernel/debug/kdb/kdb_private.h
@@ -0,0 +1,400 @@
+#ifndef _KDBPRIVATE_H
+#define _KDBPRIVATE_H
+
+/*
+ * Kernel Debugger Architecture Independent Private Headers
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+/*
+ * Kernel Debugger Error codes. Must not overlap with command codes.
+ */
+
+#include <linux/kgdb.h>
+#include "../debug_core.h"
+#define KDB_NOTFOUND (-1)
+#define KDB_ARGCOUNT (-2)
+#define KDB_BADWIDTH (-3)
+#define KDB_BADRADIX (-4)
+#define KDB_NOTENV (-5)
+#define KDB_NOENVVALUE (-6)
+#define KDB_NOTIMP (-7)
+#define KDB_ENVFULL (-8)
+#define KDB_ENVBUFFULL (-9)
+#define KDB_TOOMANYBPT (-10)
+#define KDB_TOOMANYDBREGS (-11)
+#define KDB_DUPBPT (-12)
+#define KDB_BPTNOTFOUND (-13)
+#define KDB_BADMODE (-14)
+#define KDB_BADINT (-15)
+#define KDB_INVADDRFMT (-16)
+#define KDB_BADREG (-17)
+#define KDB_BADCPUNUM (-18)
+#define KDB_BADLENGTH (-19)
+#define KDB_NOBP (-20)
+#define KDB_BADADDR (-21)
+
+ /*
+ * Kernel Debugger Command codes. Must not overlap with error codes.
+ */
+#define KDB_CMD_GO (-1001)
+#define KDB_CMD_CPU (-1002)
+#define KDB_CMD_SS (-1003)
+#define KDB_CMD_SSB (-1004)
+#define KDB_CMD_KGDB (-1005)
+#define KDB_CMD_KGDB2 (-1006)
+
+ /*
+ * Internal debug flags
+ */
+#define KDB_DEBUG_FLAG_BP 0x0002 /* Breakpoint subsystem debug */
+#define KDB_DEBUG_FLAG_BB_SUMM 0x0004 /* Basic block analysis, summary only */
+#define KDB_DEBUG_FLAG_AR 0x0008 /* Activation record, generic */
+#define KDB_DEBUG_FLAG_ARA 0x0010 /* Activation record, arch specific */
+#define KDB_DEBUG_FLAG_BB 0x0020 /* All basic block analysis */
+#define KDB_DEBUG_FLAG_STATE 0x0040 /* State flags */
+#define KDB_DEBUG_FLAG_MASK 0xffff /* All debug flags */
+#define KDB_DEBUG_FLAG_SHIFT 16 /* Shift factor for dbflags */
+
+#define KDB_DEBUG(flag) (kdb_flags & \
+ (KDB_DEBUG_FLAG_##flag << KDB_DEBUG_FLAG_SHIFT))
+#define KDB_DEBUG_STATE(text, value) if (KDB_DEBUG(STATE)) \
+ kdb_print_state(text, value)
+
+#if BITS_PER_LONG == 32
+
+#define KDB_PLATFORM_ENV "BYTESPERWORD=4"
+
+#define kdb_machreg_fmt "0x%lx"
+#define kdb_machreg_fmt0 "0x%08lx"
+#define kdb_bfd_vma_fmt "0x%lx"
+#define kdb_bfd_vma_fmt0 "0x%08lx"
+#define kdb_elfw_addr_fmt "0x%x"
+#define kdb_elfw_addr_fmt0 "0x%08x"
+#define kdb_f_count_fmt "%d"
+
+#elif BITS_PER_LONG == 64
+
+#define KDB_PLATFORM_ENV "BYTESPERWORD=8"
+
+#define kdb_machreg_fmt "0x%lx"
+#define kdb_machreg_fmt0 "0x%016lx"
+#define kdb_bfd_vma_fmt "0x%lx"
+#define kdb_bfd_vma_fmt0 "0x%016lx"
+#define kdb_elfw_addr_fmt "0x%x"
+#define kdb_elfw_addr_fmt0 "0x%016x"
+#define kdb_f_count_fmt "%ld"
+
+#endif
+
+/*
+ * KDB_MAXBPT describes the total number of breakpoints
+ * supported by this architecure.
+ */
+#define KDB_MAXBPT 16
+
+/* Maximum number of arguments to a function */
+#define KDB_MAXARGS 16
+
+typedef enum {
+ KDB_REPEAT_NONE = 0, /* Do not repeat this command */
+ KDB_REPEAT_NO_ARGS, /* Repeat the command without arguments */
+ KDB_REPEAT_WITH_ARGS, /* Repeat the command including its arguments */
+} kdb_repeat_t;
+
+typedef int (*kdb_func_t)(int, const char **);
+
+ /*
+ * Symbol table format returned by kallsyms.
+ */
+
+typedef struct __ksymtab {
+ unsigned long value; /* Address of symbol */
+ const char *mod_name; /* Module containing symbol or
+ * "kernel" */
+ unsigned long mod_start;
+ unsigned long mod_end;
+ const char *sec_name; /* Section containing symbol */
+ unsigned long sec_start;
+ unsigned long sec_end;
+ const char *sym_name; /* Full symbol name, including
+ * any version */
+ unsigned long sym_start;
+ unsigned long sym_end;
+ } kdb_symtab_t;
+extern int kallsyms_symbol_next(char *prefix_name, int flag);
+extern int kallsyms_symbol_complete(char *prefix_name, int max_len);
+
+ /*
+ * Exported Symbols for kernel loadable modules to use.
+ */
+extern int kdb_register(char *, kdb_func_t, char *, char *, short);
+extern int kdb_register_repeat(char *, kdb_func_t, char *, char *,
+ short, kdb_repeat_t);
+extern int kdb_unregister(char *);
+
+extern int kdb_getarea_size(void *, unsigned long, size_t);
+extern int kdb_putarea_size(unsigned long, void *, size_t);
+
+/* Like get_user and put_user, kdb_getarea and kdb_putarea take variable
+ * names, not pointers. The underlying *_size functions take pointers.
+ */
+#define kdb_getarea(x, addr) kdb_getarea_size(&(x), addr, sizeof((x)))
+#define kdb_putarea(addr, x) kdb_putarea_size(addr, &(x), sizeof((x)))
+
+extern int kdb_getphysword(unsigned long *word,
+ unsigned long addr, size_t size);
+extern int kdb_getword(unsigned long *, unsigned long, size_t);
+extern int kdb_putword(unsigned long, unsigned long, size_t);
+
+extern int kdbgetularg(const char *, unsigned long *);
+extern int kdb_set(int, const char **);
+extern char *kdbgetenv(const char *);
+extern int kdbgetintenv(const char *, int *);
+extern int kdbgetaddrarg(int, const char **, int*, unsigned long *,
+ long *, char **);
+extern int kdbgetsymval(const char *, kdb_symtab_t *);
+extern int kdbnearsym(unsigned long, kdb_symtab_t *);
+extern void kdbnearsym_cleanup(void);
+extern char *kdb_strdup(const char *str, gfp_t type);
+extern void kdb_symbol_print(unsigned long, const kdb_symtab_t *, unsigned int);
+
+ /*
+ * Do we have a set of registers?
+ */
+
+#define KDB_NULL_REGS(regs) \
+ (regs == (struct pt_regs *)NULL ? \
+ kdb_printf("%s: null regs - should never happen\n", __func__), \
+ 1 : 0)
+
+ /*
+ * Routine for debugging the debugger state.
+ */
+
+extern void kdb_print_state(const char *, int);
+
+ /*
+ * Per cpu kdb state. A cpu can be under kdb control but outside kdb,
+ * for example when doing single step.
+ */
+extern int kdb_state[]; /* [NR_CPUS] */
+#define KDB_STATE_KDB 0x00000001 /* Cpu is inside kdb */
+#define KDB_STATE_LEAVING 0x00000002 /* Cpu is leaving kdb */
+#define KDB_STATE_CMD 0x00000004 /* Running a kdb command */
+#define KDB_STATE_KDB_CONTROL 0x00000008 /* This cpu is under
+ * kdb control */
+#define KDB_STATE_HOLD_CPU 0x00000010 /* Hold this cpu inside kdb */
+#define KDB_STATE_DOING_SS 0x00000020 /* Doing ss command */
+#define KDB_STATE_DOING_SSB 0x00000040 /* Doing ssb command,
+ * DOING_SS is also set */
+#define KDB_STATE_SSBPT 0x00000080 /* Install breakpoint
+ * after one ss, independent of
+ * DOING_SS */
+#define KDB_STATE_REENTRY 0x00000100 /* Valid re-entry into kdb */
+#define KDB_STATE_SUPPRESS 0x00000200 /* Suppress error messages */
+#define KDB_STATE_PAGER 0x00000400 /* pager is available */
+#define KDB_STATE_GO_SWITCH 0x00000800 /* go is switching
+ * back to initial cpu */
+#define KDB_STATE_PRINTF_LOCK 0x00001000 /* Holds kdb_printf lock */
+#define KDB_STATE_WAIT_IPI 0x00002000 /* Waiting for kdb_ipi() NMI */
+#define KDB_STATE_RECURSE 0x00004000 /* Recursive entry to kdb */
+#define KDB_STATE_IP_ADJUSTED 0x00008000 /* Restart IP has been
+ * adjusted */
+#define KDB_STATE_GO1 0x00010000 /* go only releases one cpu */
+#define KDB_STATE_KEYBOARD 0x00020000 /* kdb entered via
+ * keyboard on this cpu */
+#define KDB_STATE_KEXEC 0x00040000 /* kexec issued */
+#define KDB_STATE_DOING_KGDB 0x00080000 /* kgdb enter now issued */
+#define KDB_STATE_DOING_KGDB2 0x00100000 /* kgdb enter now issued */
+#define KDB_STATE_KGDB_TRANS 0x00200000 /* Transition to kgdb */
+#define KDB_STATE_ARCH 0xff000000 /* Reserved for arch
+ * specific use */
+
+#define KDB_STATE_CPU(flag, cpu) (kdb_state[cpu] & KDB_STATE_##flag)
+#define KDB_STATE_SET_CPU(flag, cpu) \
+ ((void)(kdb_state[cpu] |= KDB_STATE_##flag))
+#define KDB_STATE_CLEAR_CPU(flag, cpu) \
+ ((void)(kdb_state[cpu] &= ~KDB_STATE_##flag))
+
+#define KDB_STATE(flag) KDB_STATE_CPU(flag, raw_smp_processor_id())
+#define KDB_STATE_SET(flag) KDB_STATE_SET_CPU(flag, raw_smp_processor_id())
+#define KDB_STATE_CLEAR(flag) KDB_STATE_CLEAR_CPU(flag, raw_smp_processor_id())
+
+ /*
+ * kdb_nextline
+ *
+ * Contains the current line number on the screen. Used
+ * to handle the built-in pager (LINES env variable)
+ */
+extern int kdb_nextline;
+
+ /*
+ * Breakpoint state
+ *
+ * Each active and inactive breakpoint is represented by
+ * an instance of the following data structure.
+ */
+
+typedef struct _kdb_bp {
+ unsigned long bp_addr; /* Address breakpoint is present at */
+ unsigned int bp_free:1; /* This entry is available */
+ unsigned int bp_enabled:1; /* Breakpoint is active in register */
+ unsigned int bp_type:4; /* Uses hardware register */
+ unsigned int bp_installed:1; /* Breakpoint is installed */
+ unsigned int bp_delay:1; /* Do delayed bp handling */
+ unsigned int bp_delayed:1; /* Delayed breakpoint */
+ unsigned int bph_length; /* HW break length */
+} kdb_bp_t;
+
+#ifdef CONFIG_KGDB_KDB
+ /*
+ * Breakpoint handling subsystem global variables
+ */
+extern kdb_bp_t kdb_breakpoints[/* KDB_MAXBPT */];
+
+ /*
+ * KDB Command Table
+ */
+
+typedef struct _kdbtab {
+ char *cmd_name; /* Command name */
+ kdb_func_t cmd_func; /* Function to execute command */
+ char *cmd_usage; /* Usage String for this command */
+ char *cmd_help; /* Help message for this command */
+ short cmd_flags; /* Parsing flags */
+ short cmd_minlen; /* Minimum legal # command
+ * chars required */
+ kdb_repeat_t cmd_repeat; /* Does command auto repeat on enter? */
+} kdbtab_t;
+
+ /*
+ * External command function declarations
+ */
+extern int kdb_bt(int, const char **);
+
+ /*
+ * External utility function declarations
+ */
+extern char *kdb_getstr(char *, size_t, char *);
+
+ /*
+ * Breakpoint handling - External interfaces
+ */
+extern void kdb_initbptab(void);
+extern void kdb_bp_install(struct pt_regs *);
+extern void kdb_bp_remove(void);
+
+typedef enum {
+ KDB_DB_BPT, /* Breakpoint */
+ KDB_DB_SS, /* Single-step trap */
+ KDB_DB_SSB, /* Single step to branch */
+ KDB_DB_SSBPT, /* Single step over breakpoint */
+ KDB_DB_NOBPT /* Spurious breakpoint */
+} kdb_dbtrap_t;
+
+extern int kdb_main_loop(kdb_reason_t, kdb_reason_t,
+ int, kdb_dbtrap_t, struct pt_regs *);
+
+ /*
+ * Miscellaneous functions and data areas
+ */
+extern int kdb_grepping_flag;
+extern char kdb_grep_string[];
+extern int kdb_grep_leading;
+extern int kdb_grep_trailing;
+extern char *kdb_cmds[];
+extern void kdb_syslog_data(char *syslog_data[]);
+extern unsigned long kdb_task_state_string(const char *);
+extern char kdb_task_state_char (const struct task_struct *);
+extern unsigned long kdb_task_state(const struct task_struct *p,
+ unsigned long mask);
+extern void kdb_ps_suppressed(void);
+extern void kdb_ps1(const struct task_struct *p);
+extern int kdb_parse(const char *cmdstr);
+extern void kdb_print_nameval(const char *name, unsigned long val);
+extern void kdb_send_sig_info(struct task_struct *p,
+ struct siginfo *info, int seqno);
+extern void kdb_meminfo_proc_show(void);
+extern const char *kdb_walk_kallsyms(loff_t *pos);
+
+ /*
+ * Defines for kdb_symbol_print.
+ */
+#define KDB_SP_SPACEB 0x0001 /* Space before string */
+#define KDB_SP_SPACEA 0x0002 /* Space after string */
+#define KDB_SP_PAREN 0x0004 /* Parenthesis around string */
+#define KDB_SP_VALUE 0x0008 /* Print the value of the address */
+#define KDB_SP_SYMSIZE 0x0010 /* Print the size of the symbol */
+#define KDB_SP_NEWLINE 0x0020 /* Newline after string */
+#define KDB_SP_DEFAULT (KDB_SP_VALUE|KDB_SP_PAREN)
+
+/* Save data about running processes */
+
+struct kdb_running_process {
+ struct task_struct *p;
+ struct pt_regs *regs;
+ int seqno; /* kdb sequence number */
+ int irq_depth; /* irq count */
+ /*struct kdba_running_process arch; */ /* arch dependent save data */
+};
+
+extern struct kdb_running_process kdb_running_process[/* NR_CPUS */];
+
+extern void kdb_save_running_cpu(struct pt_regs *, struct task_struct *, int);
+extern int kdb_save_running(struct pt_regs *, kdb_reason_t,
+ kdb_reason_t, int, kdb_dbtrap_t);
+extern struct task_struct *kdb_curr_task(int);
+
+/* Incremented each time the main kdb loop is entered on the initial cpu,
+ * it gives some indication of how old the saved data is.
+ */
+extern int kdb_seqno;
+
+#define kdb_task_has_cpu(p) (task_curr(p))
+
+/* Simplify coexistence with NPTL */
+#define kdb_do_each_thread(g, p) do_each_thread(g, p)
+#define kdb_while_each_thread(g, p) while_each_thread(g, p)
+
+#define GFP_KDB (in_interrupt() ? GFP_ATOMIC : GFP_KERNEL)
+
+extern void *debug_kmalloc(size_t size, gfp_t flags);
+extern void debug_kfree(void *);
+extern void debug_kusage(void);
+
+extern void kdb_set_current_task(struct task_struct *);
+extern struct task_struct *kdb_current_task;
+extern struct pt_regs *kdb_current_regs;
+#ifdef CONFIG_MODULES
+extern struct list_head *kdb_modules;
+#endif /* CONFIG_MODULES */
+
+#ifndef KDB_RUNNING_PROCESS_ORIGINAL
+#define KDB_RUNNING_PROCESS_ORIGINAL kdb_running_process
+#endif
+
+extern char kdb_prompt_str[];
+extern struct seq_file kdb_seq_file;
+extern void kdb_seq_file_reset(void);
+extern void kdb_seq_file_print(void);
+/* Access to un-exported kernel internals */
+#ifdef CONFIG_PROC_FS
+extern int _meminfo_proc_show(struct seq_file *m, void *v, int lock);
+#else
+static inline int _meminfo_proc_show(struct seq_file *m, void *v, int lock)
+{
+ return 0;
+}
+#endif
+
+#define KDB_WORD_SIZE ((int)sizeof(unsigned long))
+
+#endif /* CONFIG_KGDB_KDB */
+#endif /* !_KDBPRIVATE_H */
diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c
new file mode 100644
index 0000000..1324387
--- /dev/null
+++ b/kernel/debug/kdb/kdb_support.c
@@ -0,0 +1,1007 @@
+/*
+ * Kernel Debugger Architecture Independent Support Functions
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ * 03/02/13 added new 2.5 kallsyms <xavier.bru@bull.net>
+ */
+
+#include <stdarg.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/kallsyms.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/ptrace.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/hardirq.h>
+#include <linux/delay.h>
+#include <linux/uaccess.h>
+#include <linux/seq_file.h>
+#include <linux/kdb.h>
+#include "kdb_private.h"
+
+#define KDB_SEQ_BUF_SIZE 2048
+static char kdb_seq_buf[KDB_SEQ_BUF_SIZE];
+
+static void *kdb_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ (*pos)++;
+ if (*pos >= KDB_SEQ_BUF_SIZE)
+ return NULL;
+ return pos;
+}
+
+static void *kdb_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ return (*pos < KDB_SEQ_BUF_SIZE) ? pos : NULL;
+}
+
+static void kdb_seq_stop(struct seq_file *seq, void *v)
+{
+ seq->count = 0;
+}
+
+static int kdb_seq_show(struct seq_file *seq, void *v)
+{
+ return 0;
+}
+
+static struct seq_operations kdb_seq_ops = {
+ .start = kdb_seq_start,
+ .next = kdb_seq_next,
+ .stop = kdb_seq_stop,
+ .show = kdb_seq_show,
+};
+
+struct seq_file kdb_seq_file = {
+ .buf = kdb_seq_buf,
+ .size = KDB_SEQ_BUF_SIZE,
+ .op = &kdb_seq_ops
+};
+
+void kdb_seq_file_reset(void)
+{
+ kdb_seq_file.count = 0;
+}
+
+void kdb_seq_file_print(void)
+{
+ char *ptr = kdb_seq_file.buf;
+ char *tmp;
+
+ if (kdb_seq_file.count < kdb_seq_file.size)
+ kdb_seq_file.buf[kdb_seq_file.count] = '\0';
+ else
+ kdb_seq_file.buf[kdb_seq_file.size - 1] = '\0';
+ while (ptr < &kdb_seq_file.buf[kdb_seq_file.count]) {
+ if (KDB_FLAG(CMD_INTERRUPT))
+ return;
+ tmp = strchr(ptr, '\n');
+ if (tmp)
+ *tmp = '\0';
+ kdb_printf("%s\n", ptr);
+ ptr += strlen(ptr) + 1;
+ }
+}
+
+/*
+ * kdbgetsymval - Return the address of the given symbol.
+ *
+ * Parameters:
+ * symname Character string containing symbol name
+ * symtab Structure to receive results
+ * Returns:
+ * 0 Symbol not found, symtab zero filled
+ * 1 Symbol mapped to module/symbol/section, data in symtab
+ */
+int kdbgetsymval(const char *symname, kdb_symtab_t *symtab)
+{
+ if (KDB_DEBUG(AR))
+ kdb_printf("kdbgetsymval: symname=%s, symtab=%p\n", symname,
+ symtab);
+ memset(symtab, 0, sizeof(*symtab));
+ symtab->sym_start = kallsyms_lookup_name(symname);
+ if (symtab->sym_start) {
+ if (KDB_DEBUG(AR))
+ kdb_printf("kdbgetsymval: returns 1, "
+ "symtab->sym_start=0x%lx\n",
+ symtab->sym_start);
+ return 1;
+ }
+ if (KDB_DEBUG(AR))
+ kdb_printf("kdbgetsymval: returns 0\n");
+ return 0;
+}
+EXPORT_SYMBOL(kdbgetsymval);
+
+static char *kdb_name_table[100]; /* arbitrary size */
+
+/*
+ * kdbnearsym - Return the name of the symbol with the nearest address
+ * less than 'addr'.
+ *
+ * Parameters:
+ * addr Address to check for symbol near
+ * symtab Structure to receive results
+ * Returns:
+ * 0 No sections contain this address, symtab zero filled
+ * 1 Address mapped to module/symbol/section, data in symtab
+ * Remarks:
+ * 2.6 kallsyms has a "feature" where it unpacks the name into a
+ * string. If that string is reused before the caller expects it
+ * then the caller sees its string change without warning. To
+ * avoid cluttering up the main kdb code with lots of kdb_strdup,
+ * tests and kfree calls, kdbnearsym maintains an LRU list of the
+ * last few unique strings. The list is sized large enough to
+ * hold active strings, no kdb caller of kdbnearsym makes more
+ * than ~20 later calls before using a saved value.
+ */
+int kdbnearsym(unsigned long addr, kdb_symtab_t *symtab)
+{
+ int ret = 0;
+ unsigned long symbolsize;
+ unsigned long offset;
+#define knt1_size 128 /* must be >= kallsyms table size */
+ char *knt1 = NULL;
+
+ if (KDB_DEBUG(AR))
+ kdb_printf("kdbnearsym: addr=0x%lx, symtab=%p\n", addr, symtab);
+ memset(symtab, 0, sizeof(*symtab));
+
+ if (addr < 4096)
+ goto out;
+ knt1 = debug_kmalloc(knt1_size, GFP_ATOMIC);
+ if (!knt1) {
+ kdb_printf("kdbnearsym: addr=0x%lx cannot kmalloc knt1\n",
+ addr);
+ goto out;
+ }
+ symtab->sym_name = kallsyms_lookup(addr, &symbolsize , &offset,
+ (char **)(&symtab->mod_name), knt1);
+ if (offset > 8*1024*1024) {
+ symtab->sym_name = NULL;
+ addr = offset = symbolsize = 0;
+ }
+ symtab->sym_start = addr - offset;
+ symtab->sym_end = symtab->sym_start + symbolsize;
+ ret = symtab->sym_name != NULL && *(symtab->sym_name) != '\0';
+
+ if (ret) {
+ int i;
+ /* Another 2.6 kallsyms "feature". Sometimes the sym_name is
+ * set but the buffer passed into kallsyms_lookup is not used,
+ * so it contains garbage. The caller has to work out which
+ * buffer needs to be saved.
+ *
+ * What was Rusty smoking when he wrote that code?
+ */
+ if (symtab->sym_name != knt1) {
+ strncpy(knt1, symtab->sym_name, knt1_size);
+ knt1[knt1_size-1] = '\0';
+ }
+ for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
+ if (kdb_name_table[i] &&
+ strcmp(kdb_name_table[i], knt1) == 0)
+ break;
+ }
+ if (i >= ARRAY_SIZE(kdb_name_table)) {
+ debug_kfree(kdb_name_table[0]);
+ memcpy(kdb_name_table, kdb_name_table+1,
+ sizeof(kdb_name_table[0]) *
+ (ARRAY_SIZE(kdb_name_table)-1));
+ } else {
+ debug_kfree(knt1);
+ knt1 = kdb_name_table[i];
+ memcpy(kdb_name_table+i, kdb_name_table+i+1,
+ sizeof(kdb_name_table[0]) *
+ (ARRAY_SIZE(kdb_name_table)-i-1));
+ }
+ i = ARRAY_SIZE(kdb_name_table) - 1;
+ kdb_name_table[i] = knt1;
+ symtab->sym_name = kdb_name_table[i];
+ knt1 = NULL;
+ }
+
+ if (symtab->mod_name == NULL)
+ symtab->mod_name = "kernel";
+ if (KDB_DEBUG(AR))
+ kdb_printf("kdbnearsym: returns %d symtab->sym_start=0x%lx, "
+ "symtab->mod_name=%p, symtab->sym_name=%p (%s)\n", ret,
+ symtab->sym_start, symtab->mod_name, symtab->sym_name,
+ symtab->sym_name);
+
+out:
+ debug_kfree(knt1);
+ return ret;
+}
+
+void kdbnearsym_cleanup(void)
+{
+ int i;
+ for (i = 0; i < ARRAY_SIZE(kdb_name_table); ++i) {
+ if (kdb_name_table[i]) {
+ debug_kfree(kdb_name_table[i]);
+ kdb_name_table[i] = NULL;
+ }
+ }
+}
+
+static char ks_namebuf[KSYM_NAME_LEN+1], ks_namebuf_prev[KSYM_NAME_LEN+1];
+
+/*
+ * kallsyms_symbol_complete
+ *
+ * Parameters:
+ * prefix_name prefix of a symbol name to lookup
+ * max_len maximum length that can be returned
+ * Returns:
+ * Number of symbols which match the given prefix.
+ * Notes:
+ * prefix_name is changed to contain the longest unique prefix that
+ * starts with this prefix (tab completion).
+ */
+int kallsyms_symbol_complete(char *prefix_name, int max_len)
+{
+ loff_t pos = 0;
+ int prefix_len = strlen(prefix_name), prev_len = 0;
+ int i, number = 0;
+ const char *name;
+
+ while ((name = kdb_walk_kallsyms(&pos))) {
+ if (strncmp(name, prefix_name, prefix_len) == 0) {
+ strcpy(ks_namebuf, name);
+ /* Work out the longest name that matches the prefix */
+ if (++number == 1) {
+ prev_len = min_t(int, max_len-1,
+ strlen(ks_namebuf));
+ memcpy(ks_namebuf_prev, ks_namebuf, prev_len);
+ ks_namebuf_prev[prev_len] = '\0';
+ continue;
+ }
+ for (i = 0; i < prev_len; i++) {
+ if (ks_namebuf[i] != ks_namebuf_prev[i]) {
+ prev_len = i;
+ ks_namebuf_prev[i] = '\0';
+ break;
+ }
+ }
+ }
+ }
+ if (prev_len > prefix_len)
+ memcpy(prefix_name, ks_namebuf_prev, prev_len+1);
+ return number;
+}
+
+/*
+ * kallsyms_symbol_next
+ *
+ * Parameters:
+ * prefix_name prefix of a symbol name to lookup
+ * flag 0 means search from the head, 1 means continue search.
+ * Returns:
+ * 1 if a symbol matches the given prefix.
+ * 0 if no string found
+ */
+int kallsyms_symbol_next(char *prefix_name, int flag)
+{
+ int prefix_len = strlen(prefix_name);
+ static loff_t pos;
+ const char *name;
+
+ if (!flag)
+ pos = 0;
+
+ while ((name = kdb_walk_kallsyms(&pos))) {
+ if (strncmp(name, prefix_name, prefix_len) == 0) {
+ strncpy(prefix_name, name, strlen(name)+1);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * kdb_symbol_print - Standard method for printing a symbol name and offset.
+ * Inputs:
+ * addr Address to be printed.
+ * symtab Address of symbol data, if NULL this routine does its
+ * own lookup.
+ * punc Punctuation for string, bit field.
+ * Remarks:
+ * The string and its punctuation is only printed if the address
+ * is inside the kernel, except that the value is always printed
+ * when requested.
+ */
+void kdb_symbol_print(unsigned long addr, const kdb_symtab_t *symtab_p,
+ unsigned int punc)
+{
+ kdb_symtab_t symtab, *symtab_p2;
+ if (symtab_p) {
+ symtab_p2 = (kdb_symtab_t *)symtab_p;
+ } else {
+ symtab_p2 = &symtab;
+ kdbnearsym(addr, symtab_p2);
+ }
+ if (!(symtab_p2->sym_name || (punc & KDB_SP_VALUE)))
+ return;
+ if (punc & KDB_SP_SPACEB)
+ kdb_printf(" ");
+ if (punc & KDB_SP_VALUE)
+ kdb_printf(kdb_machreg_fmt0, addr);
+ if (symtab_p2->sym_name) {
+ if (punc & KDB_SP_VALUE)
+ kdb_printf(" ");
+ if (punc & KDB_SP_PAREN)
+ kdb_printf("(");
+ if (strcmp(symtab_p2->mod_name, "kernel"))
+ kdb_printf("[%s]", symtab_p2->mod_name);
+ kdb_printf("%s", symtab_p2->sym_name);
+ if (addr != symtab_p2->sym_start)
+ kdb_printf("+0x%lx", addr - symtab_p2->sym_start);
+ if (punc & KDB_SP_SYMSIZE)
+ kdb_printf("/0x%lx",
+ symtab_p2->sym_end - symtab_p2->sym_start);
+ if (punc & KDB_SP_PAREN)
+ kdb_printf(")");
+ }
+ if (punc & KDB_SP_SPACEA)
+ kdb_printf(" ");
+ if (punc & KDB_SP_NEWLINE)
+ kdb_printf("\n");
+}
+
+/*
+ * kdb_strdup - kdb equivalent of strdup, for disasm code.
+ * Inputs:
+ * str The string to duplicate.
+ * type Flags to kmalloc for the new string.
+ * Returns:
+ * Address of the new string, NULL if storage could not be allocated.
+ * Remarks:
+ * This is not in lib/string.c because it uses kmalloc which is not
+ * available when string.o is used in boot loaders.
+ */
+char *kdb_strdup(const char *str, gfp_t type)
+{
+ int n = strlen(str)+1;
+ char *s = kmalloc(n, type);
+ if (!s)
+ return NULL;
+ return strcpy(s, str);
+}
+
+/*
+ * kdb_getarea_size - Read an area of data. The kdb equivalent of
+ * copy_from_user, with kdb messages for invalid addresses.
+ * Inputs:
+ * res Pointer to the area to receive the result.
+ * addr Address of the area to copy.
+ * size Size of the area.
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+int kdb_getarea_size(void *res, unsigned long addr, size_t size)
+{
+ int ret = probe_kernel_read((char *)res, (char *)addr, size);
+ if (ret) {
+ if (!KDB_STATE(SUPPRESS)) {
+ kdb_printf("kdb_getarea: Bad address 0x%lx\n", addr);
+ KDB_STATE_SET(SUPPRESS);
+ }
+ ret = KDB_BADADDR;
+ } else {
+ KDB_STATE_CLEAR(SUPPRESS);
+ }
+ return ret;
+}
+
+/*
+ * kdb_putarea_size - Write an area of data. The kdb equivalent of
+ * copy_to_user, with kdb messages for invalid addresses.
+ * Inputs:
+ * addr Address of the area to write to.
+ * res Pointer to the area holding the data.
+ * size Size of the area.
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+int kdb_putarea_size(unsigned long addr, void *res, size_t size)
+{
+ int ret = probe_kernel_read((char *)addr, (char *)res, size);
+ if (ret) {
+ if (!KDB_STATE(SUPPRESS)) {
+ kdb_printf("kdb_putarea: Bad address 0x%lx\n", addr);
+ KDB_STATE_SET(SUPPRESS);
+ }
+ ret = KDB_BADADDR;
+ } else {
+ KDB_STATE_CLEAR(SUPPRESS);
+ }
+ return ret;
+}
+
+/*
+ * kdb_getphys - Read data from a physical address. Validate the
+ * address is in range, use kmap_atomic() to get data
+ * similar to kdb_getarea() - but for phys addresses
+ * Inputs:
+ * res Pointer to the word to receive the result
+ * addr Physical address of the area to copy
+ * size Size of the area
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+static int kdb_getphys(void *res, unsigned long addr, size_t size)
+{
+ unsigned long pfn;
+ void *vaddr;
+ struct page *page;
+
+ pfn = (addr >> PAGE_SHIFT);
+ if (!pfn_valid(pfn))
+ return 1;
+ page = pfn_to_page(pfn);
+ vaddr = kmap_atomic(page, KM_KDB);
+ memcpy(res, vaddr + (addr & (PAGE_SIZE - 1)), size);
+ kunmap_atomic(vaddr, KM_KDB);
+
+ return 0;
+}
+
+/*
+ * kdb_getphysword
+ * Inputs:
+ * word Pointer to the word to receive the result.
+ * addr Address of the area to copy.
+ * size Size of the area.
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+int kdb_getphysword(unsigned long *word, unsigned long addr, size_t size)
+{
+ int diag;
+ __u8 w1;
+ __u16 w2;
+ __u32 w4;
+ __u64 w8;
+ *word = 0; /* Default value if addr or size is invalid */
+
+ switch (size) {
+ case 1:
+ diag = kdb_getphys(&w1, addr, sizeof(w1));
+ if (!diag)
+ *word = w1;
+ break;
+ case 2:
+ diag = kdb_getphys(&w2, addr, sizeof(w2));
+ if (!diag)
+ *word = w2;
+ break;
+ case 4:
+ diag = kdb_getphys(&w4, addr, sizeof(w4));
+ if (!diag)
+ *word = w4;
+ break;
+ case 8:
+ if (size <= sizeof(*word)) {
+ diag = kdb_getphys(&w8, addr, sizeof(w8));
+ if (!diag)
+ *word = w8;
+ break;
+ }
+ /* drop through */
+ default:
+ diag = KDB_BADWIDTH;
+ kdb_printf("kdb_getphysword: bad width %ld\n", (long) size);
+ }
+ return diag;
+}
+
+/*
+ * kdb_getword - Read a binary value. Unlike kdb_getarea, this treats
+ * data as numbers.
+ * Inputs:
+ * word Pointer to the word to receive the result.
+ * addr Address of the area to copy.
+ * size Size of the area.
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+int kdb_getword(unsigned long *word, unsigned long addr, size_t size)
+{
+ int diag;
+ __u8 w1;
+ __u16 w2;
+ __u32 w4;
+ __u64 w8;
+ *word = 0; /* Default value if addr or size is invalid */
+ switch (size) {
+ case 1:
+ diag = kdb_getarea(w1, addr);
+ if (!diag)
+ *word = w1;
+ break;
+ case 2:
+ diag = kdb_getarea(w2, addr);
+ if (!diag)
+ *word = w2;
+ break;
+ case 4:
+ diag = kdb_getarea(w4, addr);
+ if (!diag)
+ *word = w4;
+ break;
+ case 8:
+ if (size <= sizeof(*word)) {
+ diag = kdb_getarea(w8, addr);
+ if (!diag)
+ *word = w8;
+ break;
+ }
+ /* drop through */
+ default:
+ diag = KDB_BADWIDTH;
+ kdb_printf("kdb_getword: bad width %ld\n", (long) size);
+ }
+ return diag;
+}
+
+/*
+ * kdb_putword - Write a binary value. Unlike kdb_putarea, this
+ * treats data as numbers.
+ * Inputs:
+ * addr Address of the area to write to..
+ * word The value to set.
+ * size Size of the area.
+ * Returns:
+ * 0 for success, < 0 for error.
+ */
+int kdb_putword(unsigned long addr, unsigned long word, size_t size)
+{
+ int diag;
+ __u8 w1;
+ __u16 w2;
+ __u32 w4;
+ __u64 w8;
+ switch (size) {
+ case 1:
+ w1 = word;
+ diag = kdb_putarea(addr, w1);
+ break;
+ case 2:
+ w2 = word;
+ diag = kdb_putarea(addr, w2);
+ break;
+ case 4:
+ w4 = word;
+ diag = kdb_putarea(addr, w4);
+ break;
+ case 8:
+ if (size <= sizeof(word)) {
+ w8 = word;
+ diag = kdb_putarea(addr, w8);
+ break;
+ }
+ /* drop through */
+ default:
+ diag = KDB_BADWIDTH;
+ kdb_printf("kdb_putword: bad width %ld\n", (long) size);
+ }
+ return diag;
+}
+
+/*
+ * kdb_task_state_string - Convert a string containing any of the
+ * letters DRSTCZEUIMA to a mask for the process state field and
+ * return the value. If no argument is supplied, return the mask
+ * that corresponds to environment variable PS, DRSTCZEU by
+ * default.
+ * Inputs:
+ * s String to convert
+ * Returns:
+ * Mask for process state.
+ * Notes:
+ * The mask folds data from several sources into a single long value, so
+ * be carefull not to overlap the bits. TASK_* bits are in the LSB,
+ * special cases like UNRUNNABLE are in the MSB. As of 2.6.10-rc1 there
+ * is no overlap between TASK_* and EXIT_* but that may not always be
+ * true, so EXIT_* bits are shifted left 16 bits before being stored in
+ * the mask.
+ */
+
+/* unrunnable is < 0 */
+#define UNRUNNABLE (1UL << (8*sizeof(unsigned long) - 1))
+#define RUNNING (1UL << (8*sizeof(unsigned long) - 2))
+#define IDLE (1UL << (8*sizeof(unsigned long) - 3))
+#define DAEMON (1UL << (8*sizeof(unsigned long) - 4))
+
+unsigned long kdb_task_state_string(const char *s)
+{
+ long res = 0;
+ if (!s) {
+ s = kdbgetenv("PS");
+ if (!s)
+ s = "DRSTCZEU"; /* default value for ps */
+ }
+ while (*s) {
+ switch (*s) {
+ case 'D':
+ res |= TASK_UNINTERRUPTIBLE;
+ break;
+ case 'R':
+ res |= RUNNING;
+ break;
+ case 'S':
+ res |= TASK_INTERRUPTIBLE;
+ break;
+ case 'T':
+ res |= TASK_STOPPED;
+ break;
+ case 'C':
+ res |= TASK_TRACED;
+ break;
+ case 'Z':
+ res |= EXIT_ZOMBIE << 16;
+ break;
+ case 'E':
+ res |= EXIT_DEAD << 16;
+ break;
+ case 'U':
+ res |= UNRUNNABLE;
+ break;
+ case 'I':
+ res |= IDLE;
+ break;
+ case 'M':
+ res |= DAEMON;
+ break;
+ case 'A':
+ res = ~0UL;
+ break;
+ default:
+ kdb_printf("%s: unknown flag '%c' ignored\n",
+ __func__, *s);
+ break;
+ }
+ ++s;
+ }
+ return res;
+}
+
+/*
+ * kdb_task_state_char - Return the character that represents the task state.
+ * Inputs:
+ * p struct task for the process
+ * Returns:
+ * One character to represent the task state.
+ */
+char kdb_task_state_char (const struct task_struct *p)
+{
+ int cpu = kdb_process_cpu(p);
+ struct kdb_running_process *krp = kdb_running_process + cpu;
+ char state = (p->state == 0) ? 'R' :
+ (p->state < 0) ? 'U' :
+ (p->state & TASK_UNINTERRUPTIBLE) ? 'D' :
+ (p->state & TASK_STOPPED) ? 'T' :
+ (p->state & TASK_TRACED) ? 'C' :
+ (p->exit_state & EXIT_ZOMBIE) ? 'Z' :
+ (p->exit_state & EXIT_DEAD) ? 'E' :
+ (p->state & TASK_INTERRUPTIBLE) ? 'S' : '?';
+ if (p->pid == 0) {
+ /* Idle task. Is it really idle, apart from the kdb
+ * interrupt? */
+ if (!kdb_task_has_cpu(p) || krp->irq_depth == 1) {
+ /* There is a corner case when the idle task takes an
+ * interrupt and dies in the interrupt code. It has an
+ * interrupt count of 1 but that did not come from kdb.
+ * This corner case can only occur on the initial cpu,
+ * all the others were entered via the kdb IPI.
+ */
+ if (cpu != kdb_initial_cpu ||
+ KDB_STATE_CPU(KEYBOARD, cpu))
+ state = 'I'; /* idle task */
+ }
+ } else if (!p->mm && state == 'S') {
+ state = 'M'; /* sleeping system daemon */
+ }
+ return state;
+}
+
+/*
+ * kdb_task_state - Return true if a process has the desired state
+ * given by the mask.
+ * Inputs:
+ * p struct task for the process
+ * mask mask from kdb_task_state_string to select processes
+ * Returns:
+ * True if the process matches at least one criteria defined by the mask.
+ */
+unsigned long kdb_task_state(const struct task_struct *p, unsigned long mask)
+{
+ char state[] = { kdb_task_state_char(p), '\0' };
+ return (mask & kdb_task_state_string(state)) != 0;
+}
+
+struct kdb_running_process kdb_running_process[NR_CPUS];
+
+/* Save the state of a running process and invoke kdb_main_loop. This is
+ * invoked on the current process on each cpu (assuming the cpu is responding).
+ */
+void
+kdb_save_running_cpu(struct pt_regs *regs, struct task_struct *task, int cpu)
+{
+ struct kdb_running_process *krp = kdb_running_process + cpu;
+ krp->p = task;
+ krp->regs = regs;
+ krp->seqno = kdb_seqno;
+ krp->irq_depth = kgdb_info[cpu].irq_depth;
+}
+
+/*
+ * kdb_print_nameval - Print a name and its value, converting the
+ * value to a symbol lookup if possible.
+ * Inputs:
+ * name field name to print
+ * val value of field
+ */
+void kdb_print_nameval(const char *name, unsigned long val)
+{
+ kdb_symtab_t symtab;
+ kdb_printf(" %-11.11s ", name);
+ if (kdbnearsym(val, &symtab))
+ kdb_symbol_print(val, &symtab,
+ KDB_SP_VALUE|KDB_SP_SYMSIZE|KDB_SP_NEWLINE);
+ else
+ kdb_printf("0x%lx\n", val);
+}
+
+/* Last ditch allocator for debugging, so we can still debug even when
+ * the GFP_ATOMIC pool has been exhausted. The algorithms are tuned
+ * for space usage, not for speed. One smallish memory pool, the free
+ * chain is always in ascending address order to allow coalescing,
+ * allocations are done in brute force best fit.
+ */
+
+struct debug_alloc_header {
+ u32 next; /* offset of next header from start of pool */
+ u32 size;
+ void *caller;
+};
+
+/* The memory returned by this allocator must be aligned, which means
+ * so must the header size. Do not assume that sizeof(struct
+ * debug_alloc_header) is a multiple of the alignment, explicitly
+ * calculate the overhead of this header, including the alignment.
+ * The rest of this code must not use sizeof() on any header or
+ * pointer to a header.
+ */
+#define dah_align 8
+#define dah_overhead ALIGN(sizeof(struct debug_alloc_header), dah_align)
+
+static u64 debug_alloc_pool_aligned[256*1024/dah_align]; /* 256K pool */
+static char *debug_alloc_pool = (char *)debug_alloc_pool_aligned;
+static u32 dah_first, dah_first_call = 1, dah_used, dah_used_max;
+
+/* Locking is awkward. The debug code is called from all contexts,
+ * including non maskable interrupts. A normal spinlock is not safe
+ * in NMI context. Try to get the debug allocator lock, if it cannot
+ * be obtained after a second then give up. If the lock could not be
+ * previously obtained on this cpu then only try once.
+ *
+ * sparse has no annotation for "this function _sometimes_ acquires a
+ * lock", so fudge the acquire/release notation.
+ */
+static DEFINE_SPINLOCK(dap_lock);
+static int get_dap_lock(void)
+ __acquires(dap_lock)
+{
+ static int dap_locked = -1;
+ int count;
+ if (dap_locked == smp_processor_id())
+ count = 1;
+ else
+ count = 1000;
+ while (1) {
+ if (spin_trylock(&dap_lock)) {
+ dap_locked = -1;
+ return 1;
+ }
+ if (!count--)
+ break;
+ udelay(1000);
+ }
+ dap_locked = smp_processor_id();
+ __acquire(dap_lock);
+ return 0;
+}
+
+void *debug_kmalloc(size_t size, gfp_t flags)
+{
+ unsigned int rem, h_offset;
+ struct debug_alloc_header *best, *bestprev, *prev, *h;
+ void *p = NULL;
+ if (!get_dap_lock()) {
+ __release(dap_lock); /* we never actually got it */
+ return NULL;
+ }
+ h = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
+ if (dah_first_call) {
+ h->size = sizeof(debug_alloc_pool_aligned) - dah_overhead;
+ dah_first_call = 0;
+ }
+ size = ALIGN(size, dah_align);
+ prev = best = bestprev = NULL;
+ while (1) {
+ if (h->size >= size && (!best || h->size < best->size)) {
+ best = h;
+ bestprev = prev;
+ if (h->size == size)
+ break;
+ }
+ if (!h->next)
+ break;
+ prev = h;
+ h = (struct debug_alloc_header *)(debug_alloc_pool + h->next);
+ }
+ if (!best)
+ goto out;
+ rem = best->size - size;
+ /* The pool must always contain at least one header */
+ if (best->next == 0 && bestprev == NULL && rem < dah_overhead)
+ goto out;
+ if (rem >= dah_overhead) {
+ best->size = size;
+ h_offset = ((char *)best - debug_alloc_pool) +
+ dah_overhead + best->size;
+ h = (struct debug_alloc_header *)(debug_alloc_pool + h_offset);
+ h->size = rem - dah_overhead;
+ h->next = best->next;
+ } else
+ h_offset = best->next;
+ best->caller = __builtin_return_address(0);
+ dah_used += best->size;
+ dah_used_max = max(dah_used, dah_used_max);
+ if (bestprev)
+ bestprev->next = h_offset;
+ else
+ dah_first = h_offset;
+ p = (char *)best + dah_overhead;
+ memset(p, POISON_INUSE, best->size - 1);
+ *((char *)p + best->size - 1) = POISON_END;
+out:
+ spin_unlock(&dap_lock);
+ return p;
+}
+
+void debug_kfree(void *p)
+{
+ struct debug_alloc_header *h;
+ unsigned int h_offset;
+ if (!p)
+ return;
+ if ((char *)p < debug_alloc_pool ||
+ (char *)p >= debug_alloc_pool + sizeof(debug_alloc_pool_aligned)) {
+ kfree(p);
+ return;
+ }
+ if (!get_dap_lock()) {
+ __release(dap_lock); /* we never actually got it */
+ return; /* memory leak, cannot be helped */
+ }
+ h = (struct debug_alloc_header *)((char *)p - dah_overhead);
+ memset(p, POISON_FREE, h->size - 1);
+ *((char *)p + h->size - 1) = POISON_END;
+ h->caller = NULL;
+ dah_used -= h->size;
+ h_offset = (char *)h - debug_alloc_pool;
+ if (h_offset < dah_first) {
+ h->next = dah_first;
+ dah_first = h_offset;
+ } else {
+ struct debug_alloc_header *prev;
+ unsigned int prev_offset;
+ prev = (struct debug_alloc_header *)(debug_alloc_pool +
+ dah_first);
+ while (1) {
+ if (!prev->next || prev->next > h_offset)
+ break;
+ prev = (struct debug_alloc_header *)
+ (debug_alloc_pool + prev->next);
+ }
+ prev_offset = (char *)prev - debug_alloc_pool;
+ if (prev_offset + dah_overhead + prev->size == h_offset) {
+ prev->size += dah_overhead + h->size;
+ memset(h, POISON_FREE, dah_overhead - 1);
+ *((char *)h + dah_overhead - 1) = POISON_END;
+ h = prev;
+ h_offset = prev_offset;
+ } else {
+ h->next = prev->next;
+ prev->next = h_offset;
+ }
+ }
+ if (h_offset + dah_overhead + h->size == h->next) {
+ struct debug_alloc_header *next;
+ next = (struct debug_alloc_header *)
+ (debug_alloc_pool + h->next);
+ h->size += dah_overhead + next->size;
+ h->next = next->next;
+ memset(next, POISON_FREE, dah_overhead - 1);
+ *((char *)next + dah_overhead - 1) = POISON_END;
+ }
+ spin_unlock(&dap_lock);
+}
+
+void debug_kusage(void)
+{
+ struct debug_alloc_header *h_free, *h_used;
+#ifdef CONFIG_IA64
+ /* FIXME: using dah for ia64 unwind always results in a memory leak.
+ * Fix that memory leak first, then set debug_kusage_one_time = 1 for
+ * all architectures.
+ */
+ static int debug_kusage_one_time;
+#else
+ static int debug_kusage_one_time = 1;
+#endif
+ if (!get_dap_lock()) {
+ __release(dap_lock); /* we never actually got it */
+ return;
+ }
+ h_free = (struct debug_alloc_header *)(debug_alloc_pool + dah_first);
+ if (dah_first == 0 &&
+ (h_free->size == sizeof(debug_alloc_pool_aligned) - dah_overhead ||
+ dah_first_call))
+ goto out;
+ if (!debug_kusage_one_time)
+ goto out;
+ debug_kusage_one_time = 0;
+ kdb_printf("%s: debug_kmalloc memory leak dah_first %d\n",
+ __func__, dah_first);
+ if (dah_first) {
+ h_used = (struct debug_alloc_header *)debug_alloc_pool;
+ kdb_printf("%s: h_used %p size %d\n", __func__, h_used,
+ h_used->size);
+ }
+ do {
+ h_used = (struct debug_alloc_header *)
+ ((char *)h_free + dah_overhead + h_free->size);
+ kdb_printf("%s: h_used %p size %d caller %p\n",
+ __func__, h_used, h_used->size, h_used->caller);
+ h_free = (struct debug_alloc_header *)
+ (debug_alloc_pool + h_free->next);
+ } while (h_free->next);
+ h_used = (struct debug_alloc_header *)
+ ((char *)h_free + dah_overhead + h_free->size);
+ if ((char *)h_used - debug_alloc_pool !=
+ sizeof(debug_alloc_pool_aligned))
+ kdb_printf("%s: h_used %p size %d caller %p\n",
+ __func__, h_used, h_used->size, h_used->caller);
+out:
+ spin_unlock(&dap_lock);
+}
+
+/* Maintain a small stack of kdb_flags to allow recursion without disturbing
+ * the global kdb state.
+ */
+
+static int kdb_flags_stack[4], kdb_flags_index;
+
+void kdb_save_flags(void)
+{
+ BUG_ON(kdb_flags_index >= ARRAY_SIZE(kdb_flags_stack));
+ kdb_flags_stack[kdb_flags_index++] = kdb_flags;
+}
+
+void kdb_restore_flags(void)
+{
+ BUG_ON(kdb_flags_index <= 0);
+ kdb_flags = kdb_flags_stack[--kdb_flags_index];
+}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 10/40] kdb: core for kgdb back end (2 of 2)
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (8 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 09/40] kdb: core for kgdb back end (1 of 2) Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 11/40] kgdb: core changes to support kdb Jason Wessel
` (30 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, mort, linux-arch
This patch contains the hooks and instrumentation into kernel which
live outside the kernel/debug directory, which the kdb core
will call to run commands like lsmod, dmesg, bt etc...
CC: mort@sgi.com
CC: linux-arch@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/arm/include/asm/kmap_types.h | 1 +
arch/powerpc/include/asm/kmap_types.h | 1 +
fs/proc/internal.h | 4 +-
fs/proc/meminfo.c | 15 +++++++++--
fs/proc/mmu.c | 8 ++++--
include/asm-generic/kmap_types.h | 3 +-
include/linux/swap.h | 2 +
init/main.c | 6 ++++
kernel/kallsyms.c | 21 ++++++++++++++++
kernel/module.c | 4 +++
kernel/printk.c | 16 ++++++++++++
kernel/sched.c | 7 ++++-
kernel/signal.c | 42 +++++++++++++++++++++++++++++++++
mm/swapfile.c | 10 ++++++-
14 files changed, 127 insertions(+), 13 deletions(-)
diff --git a/arch/arm/include/asm/kmap_types.h b/arch/arm/include/asm/kmap_types.h
index c019949..3a9fb57 100644
--- a/arch/arm/include/asm/kmap_types.h
+++ b/arch/arm/include/asm/kmap_types.h
@@ -19,6 +19,7 @@ enum km_type {
KM_SOFTIRQ0,
KM_SOFTIRQ1,
KM_L2_CACHE,
+ KM_KDB,
KM_TYPE_NR
};
diff --git a/arch/powerpc/include/asm/kmap_types.h b/arch/powerpc/include/asm/kmap_types.h
index 9163695..bca8fdc 100644
--- a/arch/powerpc/include/asm/kmap_types.h
+++ b/arch/powerpc/include/asm/kmap_types.h
@@ -26,6 +26,7 @@ enum km_type {
KM_SOFTIRQ1,
KM_PPC_SYNC_PAGE,
KM_PPC_SYNC_ICACHE,
+ KM_KDB,
KM_TYPE_NR
};
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 1f24a3e..36d55e1 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -32,11 +32,11 @@ extern struct mm_struct *mm_for_maps(struct task_struct *);
#ifdef CONFIG_MMU
#define VMALLOC_TOTAL (VMALLOC_END - VMALLOC_START)
-extern void get_vmalloc_info(struct vmalloc_info *vmi);
+extern void get_vmalloc_info(struct vmalloc_info *vmi, int lock);
#else
#define VMALLOC_TOTAL 0UL
-#define get_vmalloc_info(vmi) \
+#define get_vmalloc_info(vmi, lock) \
do { \
(vmi)->used = 0; \
(vmi)->largest_chunk = 0; \
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index a65239c..b967cf2 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -10,6 +10,7 @@
#include <linux/seq_file.h>
#include <linux/swap.h>
#include <linux/vmstat.h>
+#include <linux/kdb.h>
#include <asm/atomic.h>
#include <asm/page.h>
#include <asm/pgtable.h>
@@ -19,7 +20,7 @@ void __attribute__((weak)) arch_report_meminfo(struct seq_file *m)
{
}
-static int meminfo_proc_show(struct seq_file *m, void *v)
+int _meminfo_proc_show(struct seq_file *m, void *v, int lock)
{
struct sysinfo i;
unsigned long committed;
@@ -34,7 +35,10 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
*/
#define K(x) ((x) << (PAGE_SHIFT - 10))
si_meminfo(&i);
- si_swapinfo(&i);
+ if (lock)
+ si_swapinfo(&i);
+ else
+ __si_swapinfo(&i);
committed = percpu_counter_read_positive(&vm_committed_as);
allowed = ((totalram_pages - hugetlb_total_pages())
* sysctl_overcommit_ratio / 100) + total_swap_pages;
@@ -44,7 +48,7 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
if (cached < 0)
cached = 0;
- get_vmalloc_info(&vmi);
+ get_vmalloc_info(&vmi, lock);
for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
pages[lru] = global_page_state(NR_LRU_BASE + lru);
@@ -161,6 +165,11 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
#undef K
}
+static int meminfo_proc_show(struct seq_file *m, void *v)
+{
+ return _meminfo_proc_show(m, v, 1);
+}
+
static int meminfo_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, meminfo_proc_show, NULL);
diff --git a/fs/proc/mmu.c b/fs/proc/mmu.c
index 8ae221d..10a0f8b 100644
--- a/fs/proc/mmu.c
+++ b/fs/proc/mmu.c
@@ -14,7 +14,7 @@
#include <asm/pgtable.h>
#include "internal.h"
-void get_vmalloc_info(struct vmalloc_info *vmi)
+void get_vmalloc_info(struct vmalloc_info *vmi, int lock)
{
struct vm_struct *vma;
unsigned long free_area_size;
@@ -30,7 +30,8 @@ void get_vmalloc_info(struct vmalloc_info *vmi)
prev_end = VMALLOC_START;
- read_lock(&vmlist_lock);
+ if (lock)
+ read_lock(&vmlist_lock);
for (vma = vmlist; vma; vma = vma->next) {
unsigned long addr = (unsigned long) vma->addr;
@@ -55,6 +56,7 @@ void get_vmalloc_info(struct vmalloc_info *vmi)
if (VMALLOC_END - prev_end > vmi->largest_chunk)
vmi->largest_chunk = VMALLOC_END - prev_end;
- read_unlock(&vmlist_lock);
+ if (lock)
+ read_unlock(&vmlist_lock);
}
}
diff --git a/include/asm-generic/kmap_types.h b/include/asm-generic/kmap_types.h
index e5f234a..97e807c 100644
--- a/include/asm-generic/kmap_types.h
+++ b/include/asm-generic/kmap_types.h
@@ -28,7 +28,8 @@ KMAP_D(15) KM_UML_USERCOPY,
KMAP_D(16) KM_IRQ_PTE,
KMAP_D(17) KM_NMI,
KMAP_D(18) KM_NMI_PTE,
-KMAP_D(19) KM_TYPE_NR
+KMAP_D(19) KM_KDB,
+KMAP_D(20) KM_TYPE_NR
};
#undef KMAP_D
diff --git a/include/linux/swap.h b/include/linux/swap.h
index a2602a8..c326282 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -312,6 +312,7 @@ extern struct page *swapin_readahead(swp_entry_t, gfp_t,
/* linux/mm/swapfile.c */
extern long nr_swap_pages;
extern long total_swap_pages;
+extern void __si_swapinfo(struct sysinfo *);
extern void si_swapinfo(struct sysinfo *);
extern swp_entry_t get_swap_page(void);
extern swp_entry_t get_swap_page_of_type(int);
@@ -377,6 +378,7 @@ static inline void mem_cgroup_uncharge_swap(swp_entry_t ent)
#define si_swapinfo(val) \
do { (val)->freeswap = (val)->totalswap = 0; } while (0)
+#define __si_swapinfo(val) si_swapinfo(val)
/* only sparc can not include linux/pagemap.h in this file
* so leave page_cache_release and release_pages undeclared... */
#define free_page_and_swap_cache(page) \
diff --git a/init/main.c b/init/main.c
index dac44a9..52a24e5 100644
--- a/init/main.c
+++ b/init/main.c
@@ -63,6 +63,7 @@
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/idr.h>
+#include <linux/kdb.h>
#include <linux/ftrace.h>
#include <linux/async.h>
#include <linux/kmemcheck.h>
@@ -647,6 +648,11 @@ asmlinkage void __init start_kernel(void)
calibrate_delay();
pidmap_init();
anon_vma_init();
+
+#ifdef CONFIG_KGDB_KDB
+ kdb_init();
+#endif /* CONFIG_KGDB_KDB */
+
#ifdef CONFIG_X86
if (efi_enabled)
efi_enter_virtual_mode();
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 8e5288a..dc08f8b 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -16,6 +16,7 @@
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/fs.h>
+#include <linux/kdb.h>
#include <linux/err.h>
#include <linux/proc_fs.h>
#include <linux/sched.h> /* for cond_resched */
@@ -515,6 +516,26 @@ static int kallsyms_open(struct inode *inode, struct file *file)
return ret;
}
+#ifdef CONFIG_KGDB_KDB
+const char *kdb_walk_kallsyms(loff_t *pos)
+{
+ static struct kallsym_iter kdb_walk_kallsyms_iter;
+ if (*pos == 0) {
+ memset(&kdb_walk_kallsyms_iter, 0,
+ sizeof(kdb_walk_kallsyms_iter));
+ reset_iter(&kdb_walk_kallsyms_iter, 0);
+ }
+ while (1) {
+ if (!update_iter(&kdb_walk_kallsyms_iter, *pos))
+ return NULL;
+ ++*pos;
+ /* Some debugging symbols have no name. Ignore them. */
+ if (kdb_walk_kallsyms_iter.name[0])
+ return kdb_walk_kallsyms_iter.name;
+ }
+}
+#endif /* CONFIG_KGDB_KDB */
+
static const struct file_operations kallsyms_operations = {
.open = kallsyms_open,
.read = seq_read,
diff --git a/kernel/module.c b/kernel/module.c
index f82386b..e59aca1 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -79,6 +79,10 @@ EXPORT_TRACEPOINT_SYMBOL(module_get);
DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
static LIST_HEAD(modules);
+#ifdef CONFIG_KGDB_KDB
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_KGDB_KDB */
+
/* Block module loading/unloading? */
int modules_disabled = 0;
diff --git a/kernel/printk.c b/kernel/printk.c
index 17463ca..9bee02e 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -420,6 +420,22 @@ SYSCALL_DEFINE3(syslog, int, type, char __user *, buf, int, len)
return do_syslog(type, buf, len);
}
+#ifdef CONFIG_KGDB_KDB
+/* kdb dmesg command needs access to the syslog buffer. do_syslog()
+ * uses locks so it cannot be used during debugging. Just tell kdb
+ * where the start and end of the physical and logical logs are. This
+ * is equivalent to do_syslog(3).
+ */
+void kdb_syslog_data(char *syslog_data[4])
+{
+ syslog_data[0] = log_buf;
+ syslog_data[1] = log_buf + log_buf_len;
+ syslog_data[2] = log_buf + log_end -
+ (logged_chars < log_buf_len ? logged_chars : log_buf_len);
+ syslog_data[3] = log_buf + log_end;
+}
+#endif /* CONFIG_KGDB_KDB */
+
/*
* Call the console drivers on a range of log_buf
*/
diff --git a/kernel/sched.c b/kernel/sched.c
index c535cc4..76fa8e1 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -9784,9 +9784,9 @@ void normalize_rt_tasks(void)
#endif /* CONFIG_MAGIC_SYSRQ */
-#ifdef CONFIG_IA64
+#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB)
/*
- * These functions are only useful for the IA64 MCA handling.
+ * These functions are only useful for the IA64 MCA handling, or kdb.
*
* They can only be called when the whole system has been
* stopped - every CPU needs to be quiescent, and no scheduling
@@ -9806,6 +9806,9 @@ struct task_struct *curr_task(int cpu)
return cpu_curr(cpu);
}
+#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */
+
+#ifdef CONFIG_IA64
/**
* set_curr_task - set the current task for a given cpu.
* @cpu: the processor in question.
diff --git a/kernel/signal.c b/kernel/signal.c
index 934ae5e..4a2df1a 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2718,3 +2718,45 @@ void __init signals_init(void)
{
sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC);
}
+
+#ifdef CONFIG_KGDB_KDB
+#include <linux/kdb.h>
+/*
+ * kdb_send_sig_info - Allows kdb to send signals without exposing
+ * signal internals. This function checks if the required locks are
+ * available before calling the main signal code, to avoid kdb
+ * deadlocks.
+ */
+void
+kdb_send_sig_info(struct task_struct *t, struct siginfo *info, int seqno)
+{
+ static struct task_struct *kdb_prev_t;
+ static int kdb_prev_seqno;
+ int sig, new_t;
+ if (!spin_trylock(&t->sighand->siglock)) {
+ kdb_printf("Can't do kill command now.\n"
+ "The sigmask lock is held somewhere else in "
+ "kernel, try again later\n");
+ return;
+ }
+ spin_unlock(&t->sighand->siglock);
+ new_t = kdb_prev_t != t || kdb_prev_seqno != seqno;
+ kdb_prev_t = t;
+ kdb_prev_seqno = seqno;
+ if (t->state != TASK_RUNNING && new_t) {
+ kdb_printf("Process is not RUNNING, sending a signal from "
+ "kdb risks deadlock\n"
+ "on the run queue locks. "
+ "The signal has _not_ been sent.\n"
+ "Reissue the kill command if you want to risk "
+ "the deadlock.\n");
+ return;
+ }
+ sig = info->si_signo;
+ if (send_sig_info(sig, info, t))
+ kdb_printf("Fail to deliver Signal %d to process %d.\n",
+ sig, t->pid);
+ else
+ kdb_printf("Signal %d is sent to process %d.\n", sig, t->pid);
+}
+#endif /* CONFIG_KGDB_KDB */
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 6c0585b..dc2039e 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -13,6 +13,7 @@
#include <linux/swap.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
+#include <linux/kdb.h>
#include <linux/namei.h>
#include <linux/shm.h>
#include <linux/blkdev.h>
@@ -2056,12 +2057,11 @@ out:
return error;
}
-void si_swapinfo(struct sysinfo *val)
+void __si_swapinfo(struct sysinfo *val)
{
unsigned int type;
unsigned long nr_to_be_unused = 0;
- spin_lock(&swap_lock);
for (type = 0; type < nr_swapfiles; type++) {
struct swap_info_struct *si = swap_info[type];
@@ -2070,6 +2070,12 @@ void si_swapinfo(struct sysinfo *val)
}
val->freeswap = nr_swap_pages + nr_to_be_unused;
val->totalswap = total_swap_pages + nr_to_be_unused;
+}
+
+void si_swapinfo(struct sysinfo *val)
+{
+ spin_lock(&swap_lock);
+ __si_swapinfo(val);
spin_unlock(&swap_lock);
}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 11/40] kgdb: core changes to support kdb
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (9 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 10/40] kdb: core for kgdb back end (2 " Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 12/40] kgdb,8250,pl011: Return immediately from console poll Jason Wessel
` (29 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
These are the minimum changes to the kgdb core in order to enable an
API to connect a new front end (kdb) to the debug core.
This patch introduces the dbg_kdb_mode variable controls where the
user level I/O is routed. It will be routed to the gdbstub (kgdb) or
to the kdb front end which is a simple shell available over the kgdboc
connection.
You can switch back and forth between kdb or the gdb stub mode of
operation dynamically. From gdb stub mode you can blindly type
"$3#33", or from the kdb mode you can enter "kgdb" to switch to the
gdb stub.
The logic in the debug core depends on kdb to look for the typical gdb
connection sequences and return immediately with KGDB_PASS_EVENT if a
gdb serial command sequence is detected. That should allow a
reasonably seamless transition between kdb -> gdb without leaving the
kernel exception state. The two gdb serial queries that kdb is
responsible for detecting are the "?" and "qSupported" packets.
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/arm/kernel/kgdb.c | 5 ++
arch/mips/kernel/kgdb.c | 5 ++
arch/powerpc/kernel/kgdb.c | 5 ++
arch/x86/kernel/kgdb.c | 5 ++
include/linux/kgdb.h | 7 ++-
kernel/debug/debug_core.c | 98 ++++++++++++++++++++++++++++++++++++-------
kernel/debug/debug_core.h | 24 +++++++++++
kernel/debug/gdbstub.c | 36 ++++++++++++++++
lib/Kconfig.kgdb | 6 +++
9 files changed, 173 insertions(+), 18 deletions(-)
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index ba8ccfe..bb17e9b 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -97,6 +97,11 @@ sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task)
gdb_regs[_CPSR] = thread_regs->ARM_cpsr;
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+ regs->ARM_pc = pc;
+}
+
static int compiled_break;
int kgdb_arch_handle_exception(int exception_vector, int signo,
diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index 50c9bb8..6ed4c83 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -180,6 +180,11 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
*(ptr++) = regs->cp0_epc;
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+ regs->cp0_epc = pc;
+}
+
/*
* Calls linux_debug_hook before the kernel dies. If KGDB is enabled,
* then try to fall into the debugger
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index b6bd1ea..7aafcc5 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -309,6 +309,11 @@ void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
(unsigned long)(((void *)gdb_regs) + NUMREGBYTES));
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+ regs->nip = pc;
+}
+
/*
* This function does PowerPC specific procesing for interfacing to gdb.
*/
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index 48384fa..135c3ec 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -659,6 +659,11 @@ unsigned long kgdb_arch_pc(int exception, struct pt_regs *regs)
return instruction_pointer(regs);
}
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ regs->ip = ip;
+}
+
struct kgdb_arch arch_kgdb_ops = {
/* Breakpoint instruction: */
.gdb_bpt_instr = { 0xcc },
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 19ec41a..4316447 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -16,10 +16,12 @@
#include <linux/serial_8250.h>
#include <linux/linkage.h>
#include <linux/init.h>
-
#include <asm/atomic.h>
+#ifdef CONFIG_HAVE_ARCH_KGDB
#include <asm/kgdb.h>
+#endif
+#ifdef CONFIG_KGDB
struct pt_regs;
/**
@@ -262,6 +264,7 @@ extern struct kgdb_arch arch_kgdb_ops;
extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
+extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
@@ -278,5 +281,5 @@ extern int kgdb_nmicallback(int cpu, void *regs);
extern int kgdb_single_step;
extern atomic_t kgdb_active;
-
+#endif /* CONFIG_KGDB */
#endif /* _KGDB_H_ */
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 91286e8..f1bc63b 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -77,6 +77,11 @@ static DEFINE_SPINLOCK(kgdb_registration_lock);
static int kgdb_con_registered;
/* determine if kgdb console output should be used */
static int kgdb_use_con;
+/* Next cpu to become the master debug core */
+int dbg_switch_cpu;
+
+/* Use kdb or gdbserver mode */
+static int dbg_kdb_mode = 1;
static int __init opt_kgdb_con(char *str)
{
@@ -301,7 +306,7 @@ int dbg_set_sw_break(unsigned long addr)
return 0;
}
-static int kgdb_deactivate_sw_breakpoints(void)
+int dbg_deactivate_sw_breakpoints(void)
{
unsigned long addr;
int error;
@@ -395,8 +400,14 @@ static int kgdb_io_ready(int print_wait)
return 1;
if (atomic_read(&kgdb_setting_breakpoint))
return 1;
- if (print_wait)
+ if (print_wait) {
+#ifdef CONFIG_KGDB_KDB
+ if (!dbg_kdb_mode)
+ printk(KERN_CRIT "KGDB: waiting... or $3#33 for KDB\n");
+#else
printk(KERN_CRIT "KGDB: Waiting for remote debugger\n");
+#endif
+ }
return 1;
}
@@ -410,7 +421,7 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
/* Panic on recursive debugger calls: */
exception_level++;
addr = kgdb_arch_pc(ks->ex_vector, ks->linux_regs);
- kgdb_deactivate_sw_breakpoints();
+ dbg_deactivate_sw_breakpoints();
/*
* If the break point removed ok at the place exception
@@ -443,11 +454,24 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
return 1;
}
+static void dbg_cpu_switch(int cpu, int next_cpu)
+{
+ /* Mark the cpu we are switching away from as a slave when it
+ * holds the kgdb_active token. This must be done so that the
+ * that all the cpus wait in for the debug core will not enter
+ * again as the master. */
+ if (cpu == atomic_read(&kgdb_active)) {
+ kgdb_info[cpu].exception_state |= DCPU_IS_SLAVE;
+ kgdb_info[cpu].exception_state &= ~DCPU_WANT_MASTER;
+ }
+ kgdb_info[next_cpu].exception_state |= DCPU_NEXT_MASTER;
+}
+
static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
{
unsigned long flags;
int sstep_tries = 100;
- int error = 0;
+ int error;
int i, cpu;
acquirelock:
/*
@@ -459,6 +483,8 @@ acquirelock:
cpu = ks->cpu;
kgdb_info[cpu].debuggerinfo = regs;
kgdb_info[cpu].task = current;
+ kgdb_info[cpu].ret_state = 0;
+ kgdb_info[cpu].irq_depth = hardirq_count() >> HARDIRQ_SHIFT;
/*
* Make sure the above info reaches the primary CPU before
* our cpu_in_kgdb[] flag setting does:
@@ -471,7 +497,11 @@ acquirelock:
* master cpu and acquire the kgdb_active lock:
*/
while (1) {
- if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) {
+cpu_loop:
+ if (kgdb_info[cpu].exception_state & DCPU_NEXT_MASTER) {
+ kgdb_info[cpu].exception_state &= ~DCPU_NEXT_MASTER;
+ goto cpu_master_loop;
+ } else if (kgdb_info[cpu].exception_state & DCPU_WANT_MASTER) {
if (atomic_cmpxchg(&kgdb_active, -1, cpu) == cpu)
break;
} else if (kgdb_info[cpu].exception_state & DCPU_IS_SLAVE) {
@@ -511,7 +541,7 @@ return_normal:
}
if (!kgdb_io_ready(1)) {
- error = 1;
+ kgdb_info[cpu].ret_state = 1;
goto kgdb_restore; /* No I/O connection, resume the system */
}
@@ -555,13 +585,28 @@ return_normal:
* in the debugger and all secondary CPUs are quiescent
*/
kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
- kgdb_deactivate_sw_breakpoints();
+ dbg_deactivate_sw_breakpoints();
kgdb_single_step = 0;
kgdb_contthread = current;
exception_level = 0;
- /* Talk to debugger with gdbserial protocol */
- error = gdb_serial_stub(ks);
+ while (1) {
+cpu_master_loop:
+ if (dbg_kdb_mode)
+ error = kdb_stub(ks);
+ else
+ error = gdb_serial_stub(ks);
+
+ if (error == DBG_PASS_EVENT) {
+ dbg_kdb_mode = !dbg_kdb_mode;
+ } else if (error == DBG_SWITCH_CPU_EVENT) {
+ dbg_cpu_switch(cpu, dbg_switch_cpu);
+ goto cpu_loop;
+ } else {
+ kgdb_info[cpu].ret_state = error;
+ break;
+ }
+ }
/* Call the I/O driver's post_exception routine */
if (dbg_io_ops->post_exception)
@@ -573,11 +618,15 @@ return_normal:
for (i = NR_CPUS-1; i >= 0; i--)
atomic_set(&passive_cpu_wait[i], 0);
/*
- * Wait till all the CPUs have quit
- * from the debugger.
+ * Wait till all the CPUs have quit from the debugger,
+ * but allow a CPU that hit an exception and is
+ * waiting to become the master to remain in the debug
+ * core.
*/
for_each_online_cpu(i) {
- while (atomic_read(&cpu_in_kgdb[i]))
+ while (atomic_read(&cpu_in_kgdb[i]) &&
+ !(kgdb_info[i].exception_state &
+ DCPU_WANT_MASTER))
cpu_relax();
}
}
@@ -596,7 +645,7 @@ kgdb_restore:
clocksource_touch_watchdog();
local_irq_restore(flags);
- return error;
+ return kgdb_info[cpu].ret_state;
}
/*
@@ -625,7 +674,8 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
return 0; /* Ouch, double exception ! */
kgdb_info[ks->cpu].exception_state |= DCPU_WANT_MASTER;
ret = kgdb_cpu_enter(ks, regs);
- kgdb_info[ks->cpu].exception_state &= ~DCPU_WANT_MASTER;
+ kgdb_info[ks->cpu].exception_state &= ~(DCPU_WANT_MASTER |
+ DCPU_IS_SLAVE);
return ret;
}
@@ -658,7 +708,7 @@ static void kgdb_console_write(struct console *co, const char *s,
/* If we're debugging, or KGDB has not connected, don't try
* and print. */
- if (!kgdb_connected || atomic_read(&kgdb_active) != -1)
+ if (!kgdb_connected || atomic_read(&kgdb_active) != -1 || dbg_kdb_mode)
return;
local_irq_save(flags);
@@ -680,8 +730,14 @@ static void sysrq_handle_dbg(int key, struct tty_struct *tty)
printk(KERN_CRIT "ERROR: No KGDB I/O module available\n");
return;
}
- if (!kgdb_connected)
+ if (!kgdb_connected) {
+#ifdef CONFIG_KGDB_KDB
+ if (!dbg_kdb_mode)
+ printk(KERN_CRIT "KGDB or $3#33 for KDB\n");
+#else
printk(KERN_CRIT "Entering KGDB\n");
+#endif
+ }
kgdb_breakpoint();
}
@@ -810,6 +866,16 @@ void kgdb_unregister_io_module(struct kgdb_io *old_dbg_io_ops)
}
EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
+int dbg_io_get_char(void)
+{
+ int ret = dbg_io_ops->read_char();
+ if (!dbg_kdb_mode)
+ return ret;
+ if (ret == 127)
+ return 8;
+ return ret;
+}
+
/**
* kgdb_breakpoint - generate breakpoint exception
*
diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h
index a111cda..cf14dae 100644
--- a/kernel/debug/debug_core.h
+++ b/kernel/debug/debug_core.h
@@ -38,6 +38,8 @@ struct debuggerinfo_struct {
void *debuggerinfo;
struct task_struct *task;
int exception_state;
+ int ret_state;
+ int irq_depth;
};
extern struct debuggerinfo_struct kgdb_info[];
@@ -48,9 +50,31 @@ extern int dbg_remove_all_break(void);
extern int dbg_set_sw_break(unsigned long addr);
extern int dbg_remove_sw_break(unsigned long addr);
extern int dbg_activate_sw_breakpoints(void);
+extern int dbg_deactivate_sw_breakpoints(void);
+
+/* polled character access to i/o module */
+extern int dbg_io_get_char(void);
+
+/* stub return value for switching between the gdbstub and kdb */
+#define DBG_PASS_EVENT -12345
+/* Switch from one cpu to another */
+#define DBG_SWITCH_CPU_EVENT -123456
+extern int dbg_switch_cpu;
/* gdbstub interface functions */
extern int gdb_serial_stub(struct kgdb_state *ks);
extern void gdbstub_msg_write(const char *s, int len);
+/* gdbstub functions used for kdb <-> gdbstub transition */
+extern int gdbstub_state(struct kgdb_state *ks, char *cmd);
+
+#ifdef CONFIG_KGDB_KDB
+extern int kdb_stub(struct kgdb_state *ks);
+#else /* ! CONFIG_KGDB_KDB */
+static inline int kdb_stub(struct kgdb_state *ks)
+{
+ return DBG_PASS_EVENT;
+}
+#endif /* CONFIG_KGDB_KDB */
+
#endif /* _DEBUG_CORE_H_ */
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index ab29bce..195ffbd 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -892,6 +892,13 @@ int gdb_serial_stub(struct kgdb_state *ks)
case 'Z': /* Break point set */
gdb_cmd_break(ks);
break;
+#ifdef CONFIG_KGDB_KDB
+ case '3': /* Escape into back into kdb */
+ if (remcom_in_buffer[1] == '\0') {
+ gdb_cmd_detachkill(ks);
+ return DBG_PASS_EVENT;
+ }
+#endif
case 'C': /* Exception passing */
tmp = gdb_cmd_exception_pass(ks);
if (tmp > 0)
@@ -937,3 +944,32 @@ kgdb_exit:
error = 1;
return error;
}
+
+int gdbstub_state(struct kgdb_state *ks, char *cmd)
+{
+ int error;
+
+ switch (cmd[0]) {
+ case 'e':
+ error = kgdb_arch_handle_exception(ks->ex_vector,
+ ks->signo,
+ ks->err_code,
+ remcom_in_buffer,
+ remcom_out_buffer,
+ ks->linux_regs);
+ return error;
+ case 's':
+ case 'c':
+ strcpy(remcom_in_buffer, cmd);
+ return 0;
+ case '?':
+ gdb_cmd_status(ks);
+ break;
+ case '\0':
+ strcpy(remcom_out_buffer, "");
+ break;
+ }
+ dbg_io_ops->write_char('+');
+ put_packet(remcom_out_buffer);
+ return 0;
+}
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 9b5d1d7..02b46de 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -57,4 +57,10 @@ config KGDB_TESTS_BOOT_STRING
information about other strings you could use beyond the
default of V1F100.
+config KGDB_KDB
+ bool "KGDB_KDB: include kdb frontend for kgdb"
+ default n
+ help
+ KDB frontend for kernel
+
endif # KGDB
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 12/40] kgdb,8250,pl011: Return immediately from console poll
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (10 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 11/40] kgdb: core changes to support kdb Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 13/40] sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code Jason Wessel
` (28 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, linux-serial
The design of kdb required that every device that can provide input to
kdb have a polling routine that exits immediately if there is no
character available.
This is required in order to get the page scrolling mechanism working,
it is also a reasonable requirement for future kgdb I/O drivers
because that allows for the possibility of multiple input channels.
NO_POLL_CHAR will be the return code to the polling routine when ever
there is no character available. There are several other console
polling drivers which can be modified, but for the prototype only the
8250 and pl011 driver have been changed to make use of this.
CC: linux-serial@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/serial/8250.c | 4 ++--
drivers/serial/amba-pl011.c | 6 +++---
include/linux/kdb.h | 1 +
include/linux/serial_core.h | 1 +
kernel/debug/debug_core.c | 2 ++
kernel/debug/gdbstub.c | 37 +++++++++++++++++++++++++++++++------
kernel/debug/kdb/kdb_debugger.c | 10 ++++++++++
7 files changed, 50 insertions(+), 11 deletions(-)
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index c3e37c8..a488c60 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1895,8 +1895,8 @@ static int serial8250_get_poll_char(struct uart_port *port)
struct uart_8250_port *up = (struct uart_8250_port *)port;
unsigned char lsr = serial_inp(up, UART_LSR);
- while (!(lsr & UART_LSR_DR))
- lsr = serial_inp(up, UART_LSR);
+ if (!(lsr & UART_LSR_DR))
+ return NO_POLL_CHAR;
return serial_inp(up, UART_RX);
}
diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c
index ef7adc8..b411115 100644
--- a/drivers/serial/amba-pl011.c
+++ b/drivers/serial/amba-pl011.c
@@ -335,9 +335,9 @@ static int pl010_get_poll_char(struct uart_port *port)
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int status;
- do {
- status = readw(uap->port.membase + UART01x_FR);
- } while (status & UART01x_FR_RXFE);
+ status = readw(uap->port.membase + UART01x_FR);
+ if (status & UART01x_FR_RXFE)
+ return NO_POLL_CHAR;
return readw(uap->port.membase + UART01x_DR);
}
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index d7fc145..bff071e 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -19,6 +19,7 @@
#include <asm/atomic.h>
#define KDB_POLL_FUNC_MAX 5
+extern int kdb_poll_idx;
/*
* kdb_initial_cpu is initialized to -1, and is set to the cpu
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 8c3dd36..d40db83 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -246,6 +246,7 @@ struct uart_ops {
#endif
};
+#define NO_POLL_CHAR 0x00ff0000
#define UART_CONFIG_TYPE (1 << 0)
#define UART_CONFIG_IRQ (1 << 1)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index f1bc63b..4a90148 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -869,6 +869,8 @@ EXPORT_SYMBOL_GPL(kgdb_unregister_io_module);
int dbg_io_get_char(void)
{
int ret = dbg_io_ops->read_char();
+ if (ret == NO_POLL_CHAR)
+ return -1;
if (!dbg_kdb_mode)
return ret;
if (ret == 127)
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index 195ffbd..6965b5c 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -30,6 +30,7 @@
#include <linux/kernel.h>
#include <linux/kgdb.h>
+#include <linux/kdb.h>
#include <linux/reboot.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
@@ -62,6 +63,30 @@ static int hex(char ch)
return -1;
}
+#ifdef CONFIG_KGDB_KDB
+static int gdbstub_read_wait(void)
+{
+ int ret = -1;
+ int i;
+
+ /* poll any additional I/O interfaces that are defined */
+ while (ret < 0)
+ for (i = 0; kdb_poll_funcs[i] != NULL; i++) {
+ ret = kdb_poll_funcs[i]();
+ if (ret > 0)
+ break;
+ }
+ return ret;
+}
+#else
+static int gdbstub_read_wait(void)
+{
+ int ret = dbg_io_ops->read_char();
+ while (ret == NO_POLL_CHAR)
+ ret = dbg_io_ops->read_char();
+ return ret;
+}
+#endif
/* scan for the sequence $<data>#<checksum> */
static void get_packet(char *buffer)
{
@@ -75,7 +100,7 @@ static void get_packet(char *buffer)
* Spin and wait around for the start character, ignore all
* other characters:
*/
- while ((ch = (dbg_io_ops->read_char())) != '$')
+ while ((ch = (gdbstub_read_wait())) != '$')
/* nothing */;
kgdb_connected = 1;
@@ -88,7 +113,7 @@ static void get_packet(char *buffer)
* now, read until a # or end of buffer is found:
*/
while (count < (BUFMAX - 1)) {
- ch = dbg_io_ops->read_char();
+ ch = gdbstub_read_wait();
if (ch == '#')
break;
checksum = checksum + ch;
@@ -98,8 +123,8 @@ static void get_packet(char *buffer)
buffer[count] = 0;
if (ch == '#') {
- xmitcsum = hex(dbg_io_ops->read_char()) << 4;
- xmitcsum += hex(dbg_io_ops->read_char());
+ xmitcsum = hex(gdbstub_read_wait()) << 4;
+ xmitcsum += hex(gdbstub_read_wait());
if (checksum != xmitcsum)
/* failed checksum */
@@ -144,10 +169,10 @@ static void put_packet(char *buffer)
dbg_io_ops->flush();
/* Now see what we get in reply. */
- ch = dbg_io_ops->read_char();
+ ch = gdbstub_read_wait();
if (ch == 3)
- ch = dbg_io_ops->read_char();
+ ch = gdbstub_read_wait();
/* If we get an ACK, we are done. */
if (ch == '+')
diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
index 4cc5a69..966ea36 100644
--- a/kernel/debug/kdb/kdb_debugger.c
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -20,7 +20,15 @@
get_char_func kdb_poll_funcs[] = {
dbg_io_get_char,
NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
};
+EXPORT_SYMBOL_GPL(kdb_poll_funcs);
+
+int kdb_poll_idx = 1;
+EXPORT_SYMBOL_GPL(kdb_poll_idx);
int kdb_stub(struct kgdb_state *ks)
{
@@ -85,6 +93,7 @@ int kdb_stub(struct kgdb_state *ks)
kdb_bp_remove();
KDB_STATE_CLEAR(DOING_SS);
KDB_STATE_CLEAR(DOING_SSB);
+ KDB_STATE_SET(PAGER);
for_each_online_cpu(i) {
kdb_save_running_cpu(kgdb_info[i].debuggerinfo,
kgdb_info[i].task, i);
@@ -108,6 +117,7 @@ int kdb_stub(struct kgdb_state *ks)
kdb_initial_cpu = -1;
kdb_current_task = NULL;
kdb_current_regs = NULL;
+ KDB_STATE_CLEAR(PAGER);
kdbnearsym_cleanup();
if (error == KDB_CMD_KGDB) {
if (KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)) {
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 13/40] sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (11 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 12/40] kgdb,8250,pl011: Return immediately from console poll Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 14/40] sparc,sunzilog: Add console polling support for sunzilog serial driver Jason Wessel
` (27 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
The sci_poll_get_char() needs to return immediately if there is no
input from the chip to process, and must return a value of
NO_POLL_CHAR.
This allows kgdboc to process multiple polled devices while kgdb is
active.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
---
drivers/serial/sh-sci.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletions(-)
diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c
index 37f0de9..d29b3fe 100644
--- a/drivers/serial/sh-sci.c
+++ b/drivers/serial/sh-sci.c
@@ -126,7 +126,11 @@ static int sci_poll_get_char(struct uart_port *port)
handle_error(port);
continue;
}
- } while (!(status & SCxSR_RDxF(port)));
+ break;
+ } while (1);
+
+ if (!(status & SCxSR_RDxF(port)))
+ return NO_POLL_CHAR;
c = sci_in(port, SCxRDR);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 14/40] sparc,sunzilog: Add console polling support for sunzilog serial driver
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (12 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 13/40] sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 15/40] kgdb: gdb "monitor" -> kdb passthrough Jason Wessel
` (26 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Allow kgdboc to work on sparc hardware with the Zilog serial chips.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
---
drivers/serial/sunzilog.c | 50 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 50 insertions(+), 0 deletions(-)
diff --git a/drivers/serial/sunzilog.c b/drivers/serial/sunzilog.c
index 2c7a66a..978b3ce 100644
--- a/drivers/serial/sunzilog.c
+++ b/drivers/serial/sunzilog.c
@@ -102,6 +102,8 @@ struct uart_sunzilog_port {
#endif
};
+static void sunzilog_putchar(struct uart_port *port, int ch);
+
#define ZILOG_CHANNEL_FROM_PORT(PORT) ((struct zilog_channel __iomem *)((PORT)->membase))
#define UART_ZILOG(PORT) ((struct uart_sunzilog_port *)(PORT))
@@ -996,6 +998,50 @@ static int sunzilog_verify_port(struct uart_port *port, struct serial_struct *se
return -EINVAL;
}
+#ifdef CONFIG_CONSOLE_POLL
+static int sunzilog_get_poll_char(struct uart_port *port)
+{
+ unsigned char ch, r1;
+ struct uart_sunzilog_port *up = (struct uart_sunzilog_port *) port;
+ struct zilog_channel __iomem *channel
+ = ZILOG_CHANNEL_FROM_PORT(&up->port);
+
+
+ r1 = read_zsreg(channel, R1);
+ if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
+ writeb(ERR_RES, &channel->control);
+ ZSDELAY();
+ ZS_WSYNC(channel);
+ }
+
+ ch = readb(&channel->control);
+ ZSDELAY();
+
+ /* This funny hack depends upon BRK_ABRT not interfering
+ * with the other bits we care about in R1.
+ */
+ if (ch & BRK_ABRT)
+ r1 |= BRK_ABRT;
+
+ if (!(ch & Rx_CH_AV))
+ return NO_POLL_CHAR;
+
+ ch = readb(&channel->data);
+ ZSDELAY();
+
+ ch &= up->parity_mask;
+ return ch;
+}
+
+static void sunzilog_put_poll_char(struct uart_port *port,
+ unsigned char ch)
+{
+ struct uart_sunzilog_port *up = (struct uart_sunzilog_port *)port;
+
+ sunzilog_putchar(&up->port, ch);
+}
+#endif /* CONFIG_CONSOLE_POLL */
+
static struct uart_ops sunzilog_pops = {
.tx_empty = sunzilog_tx_empty,
.set_mctrl = sunzilog_set_mctrl,
@@ -1013,6 +1059,10 @@ static struct uart_ops sunzilog_pops = {
.request_port = sunzilog_request_port,
.config_port = sunzilog_config_port,
.verify_port = sunzilog_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = sunzilog_get_poll_char,
+ .poll_put_char = sunzilog_put_poll_char,
+#endif
};
static int uart_chip_count;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 15/40] kgdb: gdb "monitor" -> kdb passthrough
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (13 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 14/40] sparc,sunzilog: Add console polling support for sunzilog serial driver Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 16/40] kgdboc,keyboard: Keyboard driver for kdb with kgdb Jason Wessel
` (25 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
One of the driving forces behind integrating another front end (kdb)
to the debug core is to allow front end commands to be accessible via
gdb's monitor command. It is true that you could write gdb macros to
get certain data, but you may want to just use gdb to access the
commands that are available in the kdb front end.
This patch implements the Rcmd gdb stub packet. In gdb you access
this with the "monitor" command. For instance you could type "monitor
help", "monitor lsmod" or "monitor ps A" etc...
There is no error checking or command restrictions on what you can and
cannot access at this point. Doing something like trying to set
breakpoints with the monitor command is going to cause nothing but
problems. Perhaps in the future only the commands that are actually
known to work with the gdb monitor command will be available.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/debug/debug_core.c | 2 +-
kernel/debug/debug_core.h | 2 ++
kernel/debug/gdbstub.c | 22 ++++++++++++++++++++++
kernel/debug/kdb/kdb_io.c | 13 +++++++++----
kernel/debug/kdb/kdb_private.h | 1 -
5 files changed, 34 insertions(+), 6 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 4a90148..1281d1d 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -81,7 +81,7 @@ static int kgdb_use_con;
int dbg_switch_cpu;
/* Use kdb or gdbserver mode */
-static int dbg_kdb_mode = 1;
+int dbg_kdb_mode = 1;
static int __init opt_kgdb_con(char *str)
{
diff --git a/kernel/debug/debug_core.h b/kernel/debug/debug_core.h
index cf14dae..7d374c0 100644
--- a/kernel/debug/debug_core.h
+++ b/kernel/debug/debug_core.h
@@ -67,9 +67,11 @@ extern void gdbstub_msg_write(const char *s, int len);
/* gdbstub functions used for kdb <-> gdbstub transition */
extern int gdbstub_state(struct kgdb_state *ks, char *cmd);
+extern int dbg_kdb_mode;
#ifdef CONFIG_KGDB_KDB
extern int kdb_stub(struct kgdb_state *ks);
+extern int kdb_parse(const char *cmdstr);
#else /* ! CONFIG_KGDB_KDB */
static inline int kdb_stub(struct kgdb_state *ks)
{
diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index 6965b5c..cee2c0e 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -201,6 +201,9 @@ void gdbstub_msg_write(const char *s, int len)
int wcount;
int i;
+ if (len == 0)
+ len = strlen(s);
+
/* 'O'utput */
gdbmsgbuf[0] = 'O';
@@ -690,6 +693,25 @@ static void gdb_cmd_query(struct kgdb_state *ks)
kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr));
}
break;
+#ifdef CONFIG_KGDB_KDB
+ case 'R':
+ if (strncmp(remcom_in_buffer, "qRcmd,", 6) == 0) {
+ int len = strlen(remcom_in_buffer + 6);
+
+ if ((len % 2) != 0) {
+ strcpy(remcom_out_buffer, "E01");
+ break;
+ }
+ kgdb_hex2mem(remcom_in_buffer + 6,
+ remcom_out_buffer, len);
+ len = len / 2;
+ remcom_out_buffer[len++] = 0;
+
+ kdb_parse(remcom_out_buffer);
+ strcpy(remcom_out_buffer, "OK");
+ }
+ break;
+#endif
}
}
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 01fc16d..8fcd22c 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -21,6 +21,7 @@
#include <linux/smp.h>
#include <linux/nmi.h>
#include <linux/delay.h>
+#include <linux/kgdb.h>
#include <linux/kdb.h>
#include <linux/kallsyms.h>
#include "kdb_private.h"
@@ -668,10 +669,14 @@ kdb_printit:
* Write to all consoles.
*/
retlen = strlen(kdb_buffer);
- while (c) {
- c->write(c, kdb_buffer, retlen);
- touch_nmi_watchdog();
- c = c->next;
+ if (!dbg_kdb_mode && kgdb_connected) {
+ gdbstub_msg_write(kdb_buffer, retlen);
+ } else {
+ while (c) {
+ c->write(c, kdb_buffer, retlen);
+ touch_nmi_watchdog();
+ c = c->next;
+ }
}
if (logging) {
saved_loglevel = console_loglevel;
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 768655e..2db38ff 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -317,7 +317,6 @@ extern unsigned long kdb_task_state(const struct task_struct *p,
unsigned long mask);
extern void kdb_ps_suppressed(void);
extern void kdb_ps1(const struct task_struct *p);
-extern int kdb_parse(const char *cmdstr);
extern void kdb_print_nameval(const char *name, unsigned long val);
extern void kdb_send_sig_info(struct task_struct *p,
struct siginfo *info, int seqno);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 16/40] kgdboc,keyboard: Keyboard driver for kdb with kgdb
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (14 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 15/40] kgdb: gdb "monitor" -> kdb passthrough Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 17/40] kgdb,docs: Update the kgdb docs to include kdb Jason Wessel
` (24 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Dmitry Torokhov
This patch adds in the kdb PS/2 keyboard driver. This was mostly a
direct port from the original kdb where I cleaned up the code against
checkpatch.pl and added the glue to stitch it into kgdb.
This patch also enables early kdb debug via kgdbwait and the keyboard.
All the access to configure kdb using either a serial console or the
keyboard is done via kgdboc.
If you want to use only the keyboard and want to break in early you
would add to your kernel command arguments:
kgdboc=kbd kgdbwait
If you wanted serial and or the keyboard access you could use:
kgdboc=kbd,ttyS0
You can also configure kgdboc as a kernel module or at run time with
the sysfs where you can activate and deactivate kgdb.
Turn it on:
echo kbd,ttyS0 > /sys/module/kgdboc/parameters/kgdboc
Turn it off:
echo "" > /sys/module/kgdboc/parameters/kgdboc
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
Documentation/kernel-parameters.txt | 8 +-
drivers/char/Makefile | 1 +
drivers/char/kdb_keyboard.c | 204 +++++++++++++++++++++++++++++++++++
drivers/char/kdb_keyboard.h | 143 ++++++++++++++++++++++++
drivers/serial/kgdboc.c | 67 ++++++++++--
include/linux/kgdb.h | 3 +
kernel/debug/kdb/kdb_main.c | 3 +
lib/Kconfig.kgdb | 7 ++
8 files changed, 426 insertions(+), 10 deletions(-)
create mode 100644 drivers/char/kdb_keyboard.c
create mode 100644 drivers/char/kdb_keyboard.h
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 736d456..f3be1e6 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1103,9 +1103,11 @@ and is between 256 and 4096 characters. It is defined in the file
zone if it does not.
kgdboc= [HW] kgdb over consoles.
- Requires a tty driver that supports console polling.
- (only serial supported for now)
- Format: <serial_device>[,baud]
+ Requires a tty driver that supports console polling,
+ or a supported polling keyboard driver (non-usb).
+ Serial only format: <serial_device>[,baud]
+ keyboard only format: kbd
+ keyboard and serial format: kbd,<serial_device>[,baud]
kmac= [MIPS] korina ethernet MAC address.
Configure the RouterBoard 532 series on-chip
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index f957edf..dbc579e 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_LEGACY_PTYS) += pty.o
obj-$(CONFIG_UNIX98_PTYS) += pty.o
obj-y += misc.o
obj-$(CONFIG_VT) += vt_ioctl.o vc_screen.o selection.o keyboard.o
+obj-$(CONFIG_KDB_KEYBOARD) += kdb_keyboard.o
obj-$(CONFIG_BFIN_JTAG_COMM) += bfin_jtag_comm.o
obj-$(CONFIG_CONSOLE_TRANSLATIONS) += consolemap.o consolemap_deftbl.o
obj-$(CONFIG_HW_CONSOLE) += vt.o defkeymap.o
diff --git a/drivers/char/kdb_keyboard.c b/drivers/char/kdb_keyboard.c
new file mode 100644
index 0000000..95aa102
--- /dev/null
+++ b/drivers/char/kdb_keyboard.c
@@ -0,0 +1,204 @@
+/*
+ * Kernel Debugger Architecture Dependent Console I/O handler
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.
+ *
+ * Copyright (c) 1999-2006 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ */
+
+#include <linux/kdb.h>
+#include <linux/keyboard.h>
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include "kdb_keyboard.h"
+
+
+static int kbd_exists;
+
+/*
+ * Check if the keyboard controller has a keypress for us.
+ * Some parts (Enter Release, LED change) are still blocking polled here,
+ * but hopefully they are all short.
+ */
+int kdb_get_kbd_char(void)
+{
+ int scancode, scanstatus;
+ static int shift_lock; /* CAPS LOCK state (0-off, 1-on) */
+ static int shift_key; /* Shift next keypress */
+ static int ctrl_key;
+ u_short keychar;
+
+ if (KDB_FLAG(NO_I8042) || KDB_FLAG(NO_VT_CONSOLE) ||
+ (inb(KBD_STATUS_REG) == 0xff && inb(KBD_DATA_REG) == 0xff)) {
+ kbd_exists = 0;
+ return -1;
+ }
+ kbd_exists = 1;
+
+ if ((inb(KBD_STATUS_REG) & KBD_STAT_OBF) == 0)
+ return -1;
+
+ /*
+ * Fetch the scancode
+ */
+ scancode = inb(KBD_DATA_REG);
+ scanstatus = inb(KBD_STATUS_REG);
+
+ /*
+ * Ignore mouse events.
+ */
+ if (scanstatus & KBD_STAT_MOUSE_OBF)
+ return -1;
+
+ /*
+ * Ignore release, trigger on make
+ * (except for shift keys, where we want to
+ * keep the shift state so long as the key is
+ * held down).
+ */
+
+ if (((scancode&0x7f) == 0x2a) || ((scancode&0x7f) == 0x36)) {
+ /*
+ * Next key may use shift table
+ */
+ if ((scancode & 0x80) == 0)
+ shift_key = 1;
+ else
+ shift_key = 0;
+ return -1;
+ }
+
+ if ((scancode&0x7f) == 0x1d) {
+ /*
+ * Left ctrl key
+ */
+ if ((scancode & 0x80) == 0)
+ ctrl_key = 1;
+ else
+ ctrl_key = 0;
+ return -1;
+ }
+
+ if ((scancode & 0x80) != 0)
+ return -1;
+
+ scancode &= 0x7f;
+
+ /*
+ * Translate scancode
+ */
+
+ if (scancode == 0x3a) {
+ /*
+ * Toggle caps lock
+ */
+ shift_lock ^= 1;
+
+#ifdef KDB_BLINK_LED
+ kdb_toggleled(0x4);
+#endif
+ return -1;
+ }
+
+ if (scancode == 0x0e) {
+ /*
+ * Backspace
+ */
+ return 8;
+ }
+
+ /* Special Key */
+ switch (scancode) {
+ case 0xF: /* Tab */
+ return 9;
+ case 0x53: /* Del */
+ return 4;
+ case 0x47: /* Home */
+ return 1;
+ case 0x4F: /* End */
+ return 5;
+ case 0x4B: /* Left */
+ return 2;
+ case 0x48: /* Up */
+ return 16;
+ case 0x50: /* Down */
+ return 14;
+ case 0x4D: /* Right */
+ return 6;
+ }
+
+ if (scancode == 0xe0)
+ return -1;
+
+ /*
+ * For Japanese 86/106 keyboards
+ * See comment in drivers/char/pc_keyb.c.
+ * - Masahiro Adegawa
+ */
+ if (scancode == 0x73)
+ scancode = 0x59;
+ else if (scancode == 0x7d)
+ scancode = 0x7c;
+
+ if (!shift_lock && !shift_key && !ctrl_key) {
+ keychar = plain_map[scancode];
+ } else if ((shift_lock || shift_key) && key_maps[1]) {
+ keychar = key_maps[1][scancode];
+ } else if (ctrl_key && key_maps[4]) {
+ keychar = key_maps[4][scancode];
+ } else {
+ keychar = 0x0020;
+ kdb_printf("Unknown state/scancode (%d)\n", scancode);
+ }
+ keychar &= 0x0fff;
+ if (keychar == '\t')
+ keychar = ' ';
+ switch (KTYP(keychar)) {
+ case KT_LETTER:
+ case KT_LATIN:
+ if (isprint(keychar))
+ break; /* printable characters */
+ /* drop through */
+ case KT_SPEC:
+ if (keychar == K_ENTER)
+ break;
+ /* drop through */
+ default:
+ return -1; /* ignore unprintables */
+ }
+
+ if ((scancode & 0x7f) == 0x1c) {
+ /*
+ * enter key. All done. Absorb the release scancode.
+ */
+ while ((inb(KBD_STATUS_REG) & KBD_STAT_OBF) == 0)
+ ;
+
+ /*
+ * Fetch the scancode
+ */
+ scancode = inb(KBD_DATA_REG);
+ scanstatus = inb(KBD_STATUS_REG);
+
+ while (scanstatus & KBD_STAT_MOUSE_OBF) {
+ scancode = inb(KBD_DATA_REG);
+ scanstatus = inb(KBD_STATUS_REG);
+ }
+
+ if (scancode != 0x9c) {
+ /*
+ * Wasn't an enter-release, why not?
+ */
+ kdb_printf("kdb: expected enter got 0x%x status 0x%x\n",
+ scancode, scanstatus);
+ }
+
+ return 13;
+ }
+
+ return keychar & 0xff;
+}
+EXPORT_SYMBOL_GPL(kdb_get_kbd_char);
diff --git a/drivers/char/kdb_keyboard.h b/drivers/char/kdb_keyboard.h
new file mode 100644
index 0000000..5541668
--- /dev/null
+++ b/drivers/char/kdb_keyboard.h
@@ -0,0 +1,143 @@
+/*
+ * include/linux/pc_keyb.h
+ *
+ * PC Keyboard And Keyboard Controller
+ *
+ * (c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ */
+
+/*
+ * Configuration Switches
+ */
+
+#undef KBD_REPORT_ERR /* Report keyboard errors */
+#define KBD_REPORT_UNKN /* Report unknown scan codes */
+#define KBD_REPORT_TIMEOUTS /* Report keyboard timeouts */
+#undef KBD_IS_FOCUS_9000 /* We have the brain-damaged
+ * FOCUS-9000 keyboard */
+#undef INITIALIZE_MOUSE /* Define if your PS/2 mouse
+ * needs initialization. */
+
+#define KBD_INIT_TIMEOUT 1000 /* Timeout in ms for initializing the
+ * keyboard */
+#define KBC_TIMEOUT 250 /* Timeout in ms for sending
+ * to keyboard controller */
+#define KBD_TIMEOUT 1000 /* Timeout in ms for keyboard
+ * command acknowledge */
+
+/*
+ * Internal variables of the driver
+ */
+
+extern unsigned char pckbd_read_mask;
+extern unsigned char aux_device_present;
+
+/*
+ * Keyboard Controller Registers on normal PCs.
+ */
+
+#define KBD_STATUS_REG 0x64 /* Status register (R) */
+#define KBD_CNTL_REG 0x64 /* Controller command register (W) */
+#define KBD_DATA_REG 0x60 /* Keyboard data register (R/W) */
+
+/*
+ * Keyboard Controller Commands
+ */
+
+#define KBD_CCMD_READ_MODE 0x20 /* Read mode bits */
+#define KBD_CCMD_WRITE_MODE 0x60 /* Write mode bits */
+#define KBD_CCMD_GET_VERSION 0xA1 /* Get controller version */
+#define KBD_CCMD_MOUSE_DISABLE 0xA7 /* Disable mouse interface */
+#define KBD_CCMD_MOUSE_ENABLE 0xA8 /* Enable mouse interface */
+#define KBD_CCMD_TEST_MOUSE 0xA9 /* Mouse interface test */
+#define KBD_CCMD_SELF_TEST 0xAA /* Controller self test */
+#define KBD_CCMD_KBD_TEST 0xAB /* Keyboard interface test */
+#define KBD_CCMD_KBD_DISABLE 0xAD /* Keyboard interface disable */
+#define KBD_CCMD_KBD_ENABLE 0xAE /* Keyboard interface enable */
+#define KBD_CCMD_WRITE_AUX_OBUF 0xD3 /* Write to output buffer as if
+ initiated by the auxiliary device */
+#define KBD_CCMD_WRITE_MOUSE 0xD4 /* Write the following byte to
+ * the mouse */
+
+/*
+ * Keyboard Commands
+ */
+
+#define KBD_CMD_SET_LEDS 0xED /* Set keyboard leds */
+#define KBD_CMD_SET_RATE 0xF3 /* Set typematic rate */
+#define KBD_CMD_ENABLE 0xF4 /* Enable scanning */
+#define KBD_CMD_DISABLE 0xF5 /* Disable scanning */
+#define KBD_CMD_RESET 0xFF /* Reset */
+
+/*
+ * Keyboard Replies
+ */
+
+#define KBD_REPLY_POR 0xAA /* Power on reset */
+#define KBD_REPLY_ACK 0xFA /* Command ACK */
+#define KBD_REPLY_RESEND 0xFE /* Command NACK, send the cmd again */
+
+/*
+ * Status Register Bits
+ */
+
+#define KBD_STAT_OBF 0x01 /* Keyboard output buffer full */
+#define KBD_STAT_IBF 0x02 /* Keyboard input buffer full */
+#define KBD_STAT_SELFTEST 0x04 /* Self test successful */
+#define KBD_STAT_CMD 0x08 /* Last write was a command
+ * write (0=data) */
+#define KBD_STAT_UNLOCKED 0x10 /* Zero if keyboard locked */
+#define KBD_STAT_MOUSE_OBF 0x20 /* Mouse output buffer full */
+#define KBD_STAT_GTO 0x40 /* General receive/xmit timeout */
+#define KBD_STAT_PERR 0x80 /* Parity error */
+
+#define AUX_STAT_OBF (KBD_STAT_OBF | KBD_STAT_MOUSE_OBF)
+
+/*
+ * Controller Mode Register Bits
+ */
+
+#define KBD_MODE_KBD_INT 0x01 /* Keyboard data generate IRQ1 */
+#define KBD_MODE_MOUSE_INT 0x02 /* Mouse data generate IRQ12 */
+#define KBD_MODE_SYS 0x04 /* The system flag (?) */
+#define KBD_MODE_NO_KEYLOCK 0x08 /* The keylock doesn't affect
+ * the keyboard if set */
+#define KBD_MODE_DISABLE_KBD 0x10 /* Disable keyboard interface */
+#define KBD_MODE_DISABLE_MOUSE 0x20 /* Disable mouse interface */
+#define KBD_MODE_KCC 0x40 /* Scan code conversion to PC format */
+#define KBD_MODE_RFU 0x80
+
+/*
+ * Mouse Commands
+ */
+
+#define AUX_SET_RES 0xE8 /* Set resolution */
+#define AUX_SET_SCALE11 0xE6 /* Set 1:1 scaling */
+#define AUX_SET_SCALE21 0xE7 /* Set 2:1 scaling */
+#define AUX_GET_SCALE 0xE9 /* Get scaling factor */
+#define AUX_SET_STREAM 0xEA /* Set stream mode */
+#define AUX_SET_SAMPLE 0xF3 /* Set sample rate */
+#define AUX_ENABLE_DEV 0xF4 /* Enable aux device */
+#define AUX_DISABLE_DEV 0xF5 /* Disable aux device */
+#define AUX_RESET 0xFF /* Reset aux device */
+#define AUX_ACK 0xFA /* Command byte ACK. */
+
+#define AUX_BUF_SIZE 2048 /* This might be better divisible by
+ three to make overruns stay in sync
+ but then the read function would need
+ a lock etc - ick */
+
+struct aux_queue {
+ unsigned long head;
+ unsigned long tail;
+ wait_queue_head_t proc_list;
+ struct fasync_struct *fasync;
+ unsigned char buf[AUX_BUF_SIZE];
+};
+
+
+/* How to access the keyboard macros on this platform. */
+#define kbd_read_input() inb(KBD_DATA_REG)
+#define kbd_read_status() inb(KBD_STATUS_REG)
+#define kbd_write_output(val) outb(val, KBD_DATA_REG)
+#define kbd_write_command(val) outb(val, KBD_CNTL_REG)
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index eadc1ab..f4066b3 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/kgdb.h>
+#include <linux/kdb.h>
#include <linux/tty.h>
#define MAX_CONFIG_LEN 40
@@ -45,11 +46,32 @@ static int kgdboc_option_setup(char *opt)
__setup("kgdboc=", kgdboc_option_setup);
+static void cleanup_kgdboc(void)
+{
+#ifdef CONFIG_KDB_KEYBOARD
+ int i;
+
+ /* Unregister the keyboard poll hook, if registered */
+ for (i = 0; i < kdb_poll_idx; i++) {
+ if (kdb_poll_funcs[i] == kdb_get_kbd_char) {
+ kdb_poll_idx--;
+ kdb_poll_funcs[i] = kdb_poll_funcs[kdb_poll_idx];
+ kdb_poll_funcs[kdb_poll_idx] = NULL;
+ i--;
+ }
+ }
+#endif /* CONFIG_KDB_KEYBOARD */
+
+ if (configured == 1)
+ kgdb_unregister_io_module(&kgdboc_io_ops);
+}
+
static int configure_kgdboc(void)
{
struct tty_driver *p;
int tty_line = 0;
int err;
+ char *cptr = config;
err = kgdboc_option_setup(config);
if (err || !strlen(config) || isspace(config[0]))
@@ -57,13 +79,32 @@ static int configure_kgdboc(void)
err = -ENODEV;
- p = tty_find_polling_driver(config, &tty_line);
+#ifdef CONFIG_KDB_KEYBOARD
+ kgdb_tty_driver = NULL;
+
+ if (strncmp(cptr, "kbd", 3) == 0) {
+ if (kdb_poll_idx < KDB_POLL_FUNC_MAX) {
+ kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char;
+ kdb_poll_idx++;
+ if (cptr[3] == ',')
+ cptr += 4;
+ else
+ goto do_register;
+ }
+ }
+#endif /* CONFIG_KDB_KEYBOARD */
+
+ p = tty_find_polling_driver(cptr, &tty_line);
if (!p)
goto noconfig;
kgdb_tty_driver = p;
kgdb_tty_line = tty_line;
+#ifdef CONFIG_KDB_KEYBOARD
+do_register:
+#endif /* CONFIG_KDB_KEYBOARD */
+
err = kgdb_register_io_module(&kgdboc_io_ops);
if (err)
goto noconfig;
@@ -75,6 +116,7 @@ static int configure_kgdboc(void)
noconfig:
config[0] = 0;
configured = 0;
+ cleanup_kgdboc();
return err;
}
@@ -88,20 +130,18 @@ static int __init init_kgdboc(void)
return configure_kgdboc();
}
-static void cleanup_kgdboc(void)
-{
- if (configured == 1)
- kgdb_unregister_io_module(&kgdboc_io_ops);
-}
-
static int kgdboc_get_char(void)
{
+ if (!kgdb_tty_driver)
+ return -1;
return kgdb_tty_driver->ops->poll_get_char(kgdb_tty_driver,
kgdb_tty_line);
}
static void kgdboc_put_char(u8 chr)
{
+ if (!kgdb_tty_driver)
+ return;
kgdb_tty_driver->ops->poll_put_char(kgdb_tty_driver,
kgdb_tty_line, chr);
}
@@ -162,6 +202,19 @@ static struct kgdb_io kgdboc_io_ops = {
.post_exception = kgdboc_post_exp_handler,
};
+#ifdef CONFIG_KGDB_SERIAL_CONSOLE
+/* This is only available if kgdboc is a built in for early debugging */
+void __init early_kgdboc_init(void)
+{
+ /* save the first character of the config string because the
+ * init routine can destroy it.
+ */
+ char save_ch = config[0];
+ init_kgdboc();
+ config[0] = save_ch;
+}
+#endif /* CONFIG_KGDB_SERIAL_CONSOLE */
+
module_init(init_kgdboc);
module_exit(cleanup_kgdboc);
module_param_call(kgdboc, param_set_kgdboc_var, param_get_string, &kps, 0644);
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 4316447..97068ba 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -281,5 +281,8 @@ extern int kgdb_nmicallback(int cpu, void *regs);
extern int kgdb_single_step;
extern atomic_t kgdb_active;
+#ifdef CONFIG_KGDB_SERIAL_CONSOLE
+extern void __init early_kgdboc_init(void);
+#endif /* CONFIG_KGDB_SERIAL_CONSOLE */
#endif /* CONFIG_KGDB */
#endif /* _KGDB_H_ */
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 6c9826a..59bb68d 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2847,4 +2847,7 @@ void __init kdb_init(void)
kdb_initbptab(); /* Initialize Breakpoint Table */
kdb_cmd_init(); /* Preset commands from kdb_cmds */
kdb_initial_cpu = -1; /* Avoid recursion problems */
+#if defined(CONFIG_KDB_KEYBOARD) && defined(CONFIG_KGDB_SERIAL_CONSOLE)
+ early_kgdboc_init();
+#endif /* CONFIG_KDB_KEYBOARD && CONFIG_KGDB_SERIAL_CONSOLE */
}
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 02b46de..0fb633c 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -63,4 +63,11 @@ config KGDB_KDB
help
KDB frontend for kernel
+config KDB_KEYBOARD
+ bool "KGDB_KDB: keyboard as input device"
+ depends on VT && KGDB_KDB
+ default y
+ help
+ KDB can use a PS/2 type keyboard for an input device
+
endif # KGDB
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 17/40] kgdb,docs: Update the kgdb docs to include kdb
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (15 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 16/40] kgdboc,keyboard: Keyboard driver for kdb with kgdb Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 18/40] kgdb: remove post_primary_code references Jason Wessel
` (23 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Update the kgdb docs to reflect the new directory structure and API.
Merge in the kdb shell information.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
Documentation/DocBook/kgdb.tmpl | 638 ++++++++++++++++++++++++++---------
Documentation/kernel-parameters.txt | 7 +-
include/linux/kgdb.h | 12 +-
lib/Kconfig.kgdb | 2 +-
4 files changed, 493 insertions(+), 166 deletions(-)
diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl
index 5cff41a..ebae961 100644
--- a/Documentation/DocBook/kgdb.tmpl
+++ b/Documentation/DocBook/kgdb.tmpl
@@ -4,7 +4,7 @@
<book id="kgdbOnLinux">
<bookinfo>
- <title>Using kgdb and the kgdb Internals</title>
+ <title>Using kgdb, kdb and the kernel debugger internals</title>
<authorgroup>
<author>
@@ -17,33 +17,8 @@
</affiliation>
</author>
</authorgroup>
-
- <authorgroup>
- <author>
- <firstname>Tom</firstname>
- <surname>Rini</surname>
- <affiliation>
- <address>
- <email>trini@kernel.crashing.org</email>
- </address>
- </affiliation>
- </author>
- </authorgroup>
-
- <authorgroup>
- <author>
- <firstname>Amit S.</firstname>
- <surname>Kale</surname>
- <affiliation>
- <address>
- <email>amitkale@linsyssoft.com</email>
- </address>
- </affiliation>
- </author>
- </authorgroup>
-
<copyright>
- <year>2008</year>
+ <year>2008,2010</year>
<holder>Wind River Systems, Inc.</holder>
</copyright>
<copyright>
@@ -69,41 +44,76 @@
<chapter id="Introduction">
<title>Introduction</title>
<para>
- kgdb is a source level debugger for linux kernel. It is used along
- with gdb to debug a linux kernel. The expectation is that gdb can
- be used to "break in" to the kernel to inspect memory, variables
- and look through call stack information similar to what an
- application developer would use gdb for. It is possible to place
- breakpoints in kernel code and perform some limited execution
- stepping.
+ The kernel has two different debugger front ends (kdb and kgdb)
+ which interface to the debug core. It is possible to use either
+ of the debugger front ends and dynamically transition between them
+ if you configure the kernel properly at compile and runtime.
+ </para>
+ <para>
+ Kdb is simplistic shell style interface which you can use on a
+ system console with a keyboard or serial console. You can use it
+ to inspect memory, registers, process lists, dmesg, and even set
+ breakpoints to stop in a certain location. Kdb is not a source
+ level debugger, although you can set breakpoints and execute some
+ basic kernel run control. Kdb is mainly aimed at doing some
+ analysis to aid in development or diagnosing kernel problems. You
+ can access some symbols by name in kernel builtins or in kernel
+ modules if the code was built
+ with <symbol>CONFIG_KALLSYMS</symbol>.
</para>
<para>
- Two machines are required for using kgdb. One of these machines is a
- development machine and the other is a test machine. The kernel
- to be debugged runs on the test machine. The development machine
- runs an instance of gdb against the vmlinux file which contains
- the symbols (not boot image such as bzImage, zImage, uImage...).
- In gdb the developer specifies the connection parameters and
- connects to kgdb. The type of connection a developer makes with
- gdb depends on the availability of kgdb I/O modules compiled as
- builtin's or kernel modules in the test machine's kernel.
+ Kgdb was intended to be used as a source level debugger for the
+ linux kernel. It is used along with gdb to debug a linux kernel.
+ The expectation is that gdb can be used to "break in" to the
+ kernel to inspect memory, variables and look through call stack
+ information similar to the way an application developer would use
+ gdb to debug an application. It is possible to place breakpoints
+ in kernel code and perform some limited execution stepping.
+ </para>
+ <para>
+ Two machines are required for using kgdb. One of these machines is
+ a development machine and the other is the target machine. The
+ kernel to be debugged runs on the target machine. The development
+ machine runs an instance of gdb against the vmlinux file which
+ contains the symbols (not boot image such as bzImage, zImage,
+ uImage...). In gdb the developer specifies the connection
+ parameters and connects to kgdb. The type of connection a
+ developer makes with gdb depends on the availability of kgdb I/O
+ modules compiled as builtins or kernel modules in the test
+ machine's kernel.
</para>
</chapter>
<chapter id="CompilingAKernel">
- <title>Compiling a kernel</title>
+ <title>Compiling a kernel</title>
+ <para>
+ <itemizedlist>
+ <listitem><para>In order to enable compilation of kdb, you must first enable kgdb.</para></listitem>
+ <listitem><para>The kgdb test compile options are described in the kgdb test suite chapter.</para></listitem>
+ </itemizedlist>
+ </para>
+ <sect1 id="CompileKGDB">
+ <title>Kernel config options for kgdb</title>
<para>
To enable <symbol>CONFIG_KGDB</symbol> you should first turn on
"Prompt for development and/or incomplete code/drivers"
(CONFIG_EXPERIMENTAL) in "General setup", then under the
- "Kernel debugging" select "KGDB: kernel debugging with remote gdb".
+ "Kernel debugging" select "KGDB: kernel debugger".
+ </para>
+ <para>
+ While it is not a hard requirement that you have symbols in your
+ vmlinux file, gdb tends not to be very useful without the symbolic
+ data, so you will want to turn
+ on <symbol>CONFIG_DEBUG_INFO</symbol> which is called "Compile the
+ kernel with debug info" in the menu config.
</para>
<para>
It is advised, but not required that you turn on the
- CONFIG_FRAME_POINTER kernel option. This option inserts code to
- into the compiled executable which saves the frame information in
- registers or on the stack at different points which will allow a
- debugger such as gdb to more accurately construct stack back traces
- while debugging the kernel.
+ <symbol>CONFIG_FRAME_POINTER</symbol> kernel option which is called "Compile the
+ kernel with frame pointers" in the menu config. This option
+ inserts code to into the compiled executable which saves the frame
+ information in registers or on the stack at different points which
+ will allow a debugger such as gdb to more accurately construct
+ stack back traces while debugging the kernel.
</para>
<para>
If the architecture that you are using supports the kernel option
@@ -116,38 +126,145 @@
this option.
</para>
<para>
- Next you should choose one of more I/O drivers to interconnect debugging
- host and debugged target. Early boot debugging requires a KGDB
- I/O driver that supports early debugging and the driver must be
- built into the kernel directly. Kgdb I/O driver configuration
- takes place via kernel or module parameters, see following
- chapter.
+ Next you should choose one of more I/O drivers to interconnect
+ debugging host and debugged target. Early boot debugging requires
+ a KGDB I/O driver that supports early debugging and the driver
+ must be built into the kernel directly. Kgdb I/O driver
+ configuration takes place via kernel or module parameters which
+ you can learn more about in the in the section that describes the
+ kernel parameter kgdboc.
</para>
- <para>
- The kgdb test compile options are described in the kgdb test suite chapter.
+ <para>Here is an example set of .config to enable kgdb:
+ <itemizedlist>
+ <listitem><para># CONFIG_DEBUG_RODATA is not set</para></listitem>
+ <listitem><para>CONFIG_FRAME_POINTER=y</para></listitem>
+ <listitem><para>CONFIG_KGDB=y</para></listitem>
+ <listitem><para>CONFIG_KGDB_SERIAL_CONSOLE=y</para></listitem>
+ </itemizedlist>
</para>
-
+ </sect1>
+ <sect1 id="CompileKDB">
+ <title>Kernel config options for kdb</title>
+ <para>Kdb is quite a bit more complex than the simple gdbstub
+ sitting on top of the kernel's debug core. Kdb must implement an
+ shell, and also adds some helper functions in other parts of the
+ kernel, responsible for printing out interesting data such as what
+ you would see if you ran "lsmod", or "ps". In order to build kdb
+ into the kernel you follow the same steps as you would for kgdb.
+ </para>
+ <para>The main config option for kdb
+ is <symbol>CONFIG_KGDB_KDB</symbol> which is called "KGDB_KDB:
+ include kdb frontend for kgdb" in the menu config. In theory you
+ would have already also selected an I/O driver such as the
+ CONFIG_KGDB_SERIAL_CONSOLE interface if you plan on using kdb on a
+ serial port, when you were configuring kgdb.
+ </para>
+ <para>If you want to use a ps/2 style keyboard with kdb you would
+ select CONFIG_KDB_KEYBOARD which is called "KGDB_KDB: keyboard as
+ input device" in the menu config. This option really does do
+ anything for the gdb interface to kgdb it only works with kdb,
+ because it is not really meaningful to manually type in gdb
+ remote protocol commands.
+ </para>
+ <para>Here is an example set of .config to enable kdb:
+ <itemizedlist>
+ <listitem><para># CONFIG_DEBUG_RODATA is not set</para></listitem>
+ <listitem><para>CONFIG_FRAME_POINTER=y</para></listitem>
+ <listitem><para>CONFIG_KGDB=y</para></listitem>
+ <listitem><para>CONFIG_KGDB_SERIAL_CONSOLE=y</para></listitem>
+ <listitem><para>CONFIG_KGDB_KDB=y</para></listitem>
+ <listitem><para>CONFIG_KDB_KEYBOARD=y</para></listitem>
+ </itemizedlist>
+ </para>
+ </sect1>
</chapter>
- <chapter id="EnableKGDB">
- <title>Enable kgdb for debugging</title>
- <para>
- In order to use kgdb you must activate it by passing configuration
- information to one of the kgdb I/O drivers. If you do not pass any
- configuration information kgdb will not do anything at all. Kgdb
- will only actively hook up to the kernel trap hooks if a kgdb I/O
- driver is loaded and configured. If you unconfigure a kgdb I/O
- driver, kgdb will unregister all the kernel hook points.
+ <chapter id="kgdbKernelArgs">
+ <title>Kernel Debugger Boot Arguments</title>
+ <para>This section will describe the various runtime kernel
+ parameters that affect the configuration of the kernel debugger.
+ The following chapter will cover using kdb and kgdb as well as
+ provide some examples of the configuration parameters.</para>
+ <sect1 id="kgdboc">
+ <title>Kernel parameter: kgdboc</title>
+ <para>The kgdboc driver was originally an abbreviation meant to
+ stand for "kgdb over console". Today it is the primary mechanism
+ to configure how to communicate from gdb to kgdb as well as the
+ devices you want to use to interact with the kdb shell.
</para>
- <para>
- All drivers can be reconfigured at run time, if
- <symbol>CONFIG_SYSFS</symbol> and <symbol>CONFIG_MODULES</symbol>
- are enabled, by echo'ing a new config string to
- <constant>/sys/module/<driver>/parameter/<option></constant>.
- The driver can be unconfigured by passing an empty string. You cannot
- change the configuration while the debugger is attached. Make sure
- to detach the debugger with the <constant>detach</constant> command
- prior to trying unconfigure a kgdb I/O driver.
+ <para>For kgdb/gdb, kgdboc is designed to work with a single serial
+ port. It was meant to cover the circumstance where you wanted to
+ use a serial console as your primary console as well as using it to
+ perform kernel debugging. It is also possible to use kgdb on a
+ serial port which is not designated as a system console. Kgdboc
+ may be configured as a kernel built-in or a kernel module. You can
+ only make use of <constant>kgdbwait</constant> and early debugging
+ if you build kgdboc into the kernel as a builtins.
+ </para>
+ <sect2 id="kgdbocArgs">
+ <title>kgdboc arguments</title>
+ <para>Usage: <constant>kgdboc=[kbd][[,]serial_device][,baud]</constant></para>
+ <para>You can configure kgdboc to use the keyboard, and or a serial device
+ depending on if you are using kdb and or kgdb, in one of the
+ following scenarios.
+ <orderedlist>
+ <listitem><para>kdb and kgdb over only a serial port</para>
+ <para><constant>kgdboc=<serial_device>[,baud]</constant></para>
+ <para>Example: <constant>kgdboc=ttyS0,115200</constant></para>
+ </listitem>
+ <listitem><para>kdb and kgdb with keyboard and a serial port</para>
+ <para><constant>kgdboc=kbd,<serial_device>[,baud]</constant></para>
+ <para>Example: <constant>kgdboc=kbd,ttyS0,115200</constant></para>
+ </listitem>
+ <listitem><para>kdb with a keyboard</para>
+ <para><constant>kgdboc=kbd</constant></para>
+ </listitem>
+ </orderedlist>
+ </para>
+ <para>You can configure kgdboc via sysfs or a module or kernel boot line
+ parameter depending on if you build with CONFIG_KGDBOC as a module
+ or built-in.
+ <orderedlist>
+ <listitem><para>From the module load or build-in</para>
+ <para>As a kernel argument: <constant>kgdboc=<tty-device>,[baud]</constant></para>
+ <para>As a kernel module: <constant>modprobe kgdboc kgdboc=<tty-device>,[baud]</constant></para>
+ <para>Here are two examples, the first for an x86 target using the
+ first serial port and the second for the ARM Versatile AB using the
+ second serial port.
+ <orderedlist>
+ <listitem><para><constant>kgdboc=ttyS0,115200</constant></para></listitem>
+ <listitem><para><constant>kgdboc=ttyAMA1,115200</constant></para></listitem>
+ </orderedlist>
+ </para>
+ </listitem>
+ <listitem><para>From sysfs</para>
+ <para><constant>echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc</constant></para>
+ <para>NOTE: You do not need to specify the baud if you are
+ configuring the console on tty which is already configured or
+ open.</para>
+ </listitem>
+ </orderedlist>
+ </para>
+ <para>NOTE: Kgdboc does not support interrupting the target via the
+ gdb remote protocol. You must manually send a sysrq-g unless you
+ have a proxy that splits console output to a terminal problem and
+ has a separate port for the debugger to connect to that sends the
+ sysrq-g for you.
</para>
+ <para>When using kgdboc with no debugger proxy, you can end up
+ connecting the debugger for one of two entry points. If an
+ exception occurs after you have loaded kgdboc a message should
+ print on the console stating it is waiting for the debugger. In
+ case you disconnect your terminal program and then connect the
+ debugger in its place. If you want to interrupt the target system
+ and forcibly enter a debug session you have to issue a Sysrq
+ sequence and then type the letter <constant>g</constant>. Then
+ you disconnect the terminal session and connect gdb. Your options
+ if you don't like this are to hack gdb to send the sysrq-g for you
+ as well as on the initial connect, or to use a debugger proxy that
+ allows an unmodified gdb to do the debugging.
+ </para>
+ </sect2>
+ </sect1>
<sect1 id="kgdbwait">
<title>Kernel parameter: kgdbwait</title>
<para>
@@ -166,99 +283,193 @@
kgdb I/O driver as a kernel module kgdbwait will not do anything.
</para>
</sect1>
- <sect1 id="kgdboc">
- <title>Kernel parameter: kgdboc</title>
- <para>
- The kgdboc driver was originally an abbreviation meant to stand for
- "kgdb over console". Kgdboc is designed to work with a single
- serial port. It was meant to cover the circumstance
- where you wanted to use a serial console as your primary console as
- well as using it to perform kernel debugging. Of course you can
- also use kgdboc without assigning a console to the same port.
+ <sect1 id="kgdbcon">
+ <title>Kernel parameter: kgdbcon</title>
+ <para> The kgdbcon feature allows you to see printk() messages
+ inside gdb while gdb is connected to the kernel. Kdb does not make
+ use of the kgdbcon feature.
+ </para>
+ <para>Kgdb supports using the gdb serial protocol to send console
+ messages to the debugger when the debugger is connected and running.
+ There are two ways to activate this feature.
+ <orderedlist>
+ <listitem><para>Activate with the kernel command line option:</para>
+ <para><constant>kgdbcon</constant></para>
+ </listitem>
+ <listitem><para>Use sysfs before configuring an io driver</para>
+ <para>
+ <constant>echo 1 > /sys/module/kgdb/parameters/kgdb_use_con</constant>
+ </para>
+ <para>
+ NOTE: If you do this after you configure the kgdb I/O driver, the
+ setting will not take effect until the next point the I/O is
+ reconfigured.
+ </para>
+ </listitem>
+ </orderedlist>
+ <para>IMPORTANT NOTE: You cannot use kgdboc + kgdbcon on a tty that is an
+ active system console IE: console=ttyS0,115200 kgdboc=ttyS0 kgdbcon
+ </para>
+ <para>It is possible to use this option with kgdboc on a tty that is not a system console.
+ </para>
</para>
- <sect2 id="UsingKgdboc">
- <title>Using kgdboc</title>
- <para>
- You can configure kgdboc via sysfs or a module or kernel boot line
- parameter depending on if you build with CONFIG_KGDBOC as a module
- or built-in.
- <orderedlist>
- <listitem><para>From the module load or build-in</para>
- <para><constant>kgdboc=<tty-device>,[baud]</constant></para>
+ </sect1>
+ </chapter>
+ <chapter id="usingKDB">
+ <title>Using kdb</title>
<para>
- The example here would be if your console port was typically ttyS0, you would use something like <constant>kgdboc=ttyS0,115200</constant> or on the ARM Versatile AB you would likely use <constant>kgdboc=ttyAMA0,115200</constant>
+ </para>
+ <sect1 id="quickKDBserial">
+ <title>Quick start for kdb on a serial port</title>
+ <para>This is a quick example of how to use kdb</para>
+ <para><orderedlist>
+ <listitem><para>Boot kernel with arguments:
+ <itemizedlist>
+ <listitem><para><constant>console=ttyS0,115200 kgdboc=ttyS0,115200</constant></para></listitem>
+ </itemizedlist></para>
+ <para>OR</para>
+ <para>Configure kgdboc after the kernel booted assuming your are using a serial port console:
+ <itemizedlist>
+ <listitem><para><constant>echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+ </itemizedlist>
</para>
</listitem>
- <listitem><para>From sysfs</para>
- <para><constant>echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc</constant></para>
+ <listitem><para>Enter the kernel debugger manually or by waiting for an opps or fault. There are several ways you can enter the kernel debugger manually, all involve using the sysrq-g, which means you have to enabled CONFIG_MAGIC_SYSRQ=y in your kernel config</para>
+ <itemizedlist>
+ <listitem><para>When logged in as root or with a super user session you can run:</para>
+ <para><constant>echo g > /proc/sysrq-trigger</constant></para></listitem>
+ <listitem><para>Example using minicom 2.2</para>
+ <para>Press: <constant>Control-a</constant></para>
+ <para>Press: <constant>f</constant></para>
+ <para>Press: <constant>g</constant></para>
</listitem>
- </orderedlist>
- </para>
- <para>
- NOTE: Kgdboc does not support interrupting the target via the
- gdb remote protocol. You must manually send a sysrq-g unless you
- have a proxy that splits console output to a terminal problem and
- has a separate port for the debugger to connect to that sends the
- sysrq-g for you.
+ <listitem><para>When you have telneted to a terminal server that supports sending a remote break</para>
+ <para>Press: <constant>Control-]</constant></para>
+ <para>Type in:<constant>send break</constant></para>
+ <para>Press: <constant>Enter</constant></para>
+ <para>Press: <constant>g</constant></para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem><para>From the kdb prompt you can run the "help" command to see a complete list of the commands that are available.</para>
+ <para>Some useful commands in kdb include:
+ <itemizedlist>
+ <listitem><para>lsmod -- Shows where kernel modules are loaded</para></listitem>
+ <listitem><para>ps -- Displays only the active processes</para></listitem>
+ <listitem><para>ps A -- Shows all the processes</para></listitem>
+ <listitem><para>summary -- Shows kernel version info and memory usage</para></listitem>
+ <listitem><para>bt -- Get a backtrace of the current process using dump_stack()</para></listitem>
+ <listitem><para>dmesg -- View the kernel syslog buffer</para></listitem>
+ <listitem><para>go -- Continue the system</para></listitem>
+ </itemizedlist>
</para>
- <para>When using kgdboc with no debugger proxy, you can end up
- connecting the debugger for one of two entry points. If an
- exception occurs after you have loaded kgdboc a message should print
- on the console stating it is waiting for the debugger. In case you
- disconnect your terminal program and then connect the debugger in
- its place. If you want to interrupt the target system and forcibly
- enter a debug session you have to issue a Sysrq sequence and then
- type the letter <constant>g</constant>. Then you disconnect the
- terminal session and connect gdb. Your options if you don't like
- this are to hack gdb to send the sysrq-g for you as well as on the
- initial connect, or to use a debugger proxy that allows an
- unmodified gdb to do the debugging.
+ </listitem>
+ <listitem>
+ <para>When you are done using kdb you need to consider rebooting the system or using the "go" command to resuming normal kernel execution. If you have paused the kernel for a lengthy period of time, applications that rely on timely networking or anything to do with real wall clock time could get adversely affected, so you should take this into consideration when using the kernel debugger.</para>
+ </listitem>
+ </orderedlist></para>
+ </sect1>
+ <sect1 id="quickKDBkeyboard">
+ <title>Quick start for kdb using a keyboard connected console</title>
+ <para>This is a quick example of how to use kdb with a keyboard</para>
+ <para><orderedlist>
+ <listitem><para>Boot kernel with arguments:
+ <itemizedlist>
+ <listitem><para><constant>kgdboc=kbd</constant></para></listitem>
+ </itemizedlist></para>
+ <para>OR</para>
+ <para>Configure kgdboc after the kernel booted:
+ <itemizedlist>
+ <listitem><para><constant>echo kbd > /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+ </itemizedlist>
</para>
- </sect2>
+ </listitem>
+ <listitem><para>Enter the kernel debugger manually or by waiting for an opps or fault. There are several ways you can enter the kernel debugger manually, all involve using the sysrq-g, which means you have to enabled CONFIG_MAGIC_SYSRQ=y in your kernel config</para>
+ <itemizedlist>
+ <listitem><para>When logged in as root or with a super user session you can run:</para>
+ <para><constant>echo g > /proc/sysrq-trigger</constant></para></listitem>
+ <listitem><para>Example using a laptop keyboard</para>
+ <para>Press and hold down: <constant>Alt</constant></para>
+ <para>Press and hold down: <constant>Fn</constant></para>
+ <para>Press and release the key with the label: <constant>SysRq</constant></para>
+ <para>Release: <constant>Fn</constant></para>
+ <para>Press and release: <constant>g</constant></para>
+ <para>Release: <constant>Alt</constant></para>
+ </listitem>
+ <listitem><para>Example using a PS/2 101 keyboard</para>
+ <para>Press and hold down: <constant>Alt</constant></para>
+ <para>Press and release the key with the label: <constant>SysRq</constant></para>
+ <para>Press and release: <constant>g</constant></para>
+ <para>Release: <constant>Alt</constant></para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem>
+ <para>Now type in a kdb command such as "help", "dmesg", "bt" or "go" to continue kernel execution.</para>
+ </listitem>
+ </orderedlist></para>
</sect1>
- <sect1 id="kgdbcon">
- <title>Kernel parameter: kgdbcon</title>
- <para>
- Kgdb supports using the gdb serial protocol to send console messages
- to the debugger when the debugger is connected and running. There
- are two ways to activate this feature.
+ </chapter>
+ <chapter id="EnableKGDB">
+ <title>Using kgdb / gdb</title>
+ <para>In order to use kgdb you must activate it by passing
+ configuration information to one of the kgdb I/O drivers. If you
+ do not pass any configuration information kgdb will not do anything
+ at all. Kgdb will only actively hook up to the kernel trap hooks
+ if a kgdb I/O driver is loaded and configured. If you unconfigure
+ a kgdb I/O driver, kgdb will unregister all the kernel hook points.
+ </para>
+ <para> All kgdb I/O drivers can be reconfigured at run time, if
+ <symbol>CONFIG_SYSFS</symbol> and <symbol>CONFIG_MODULES</symbol>
+ are enabled, by echo'ing a new config string to
+ <constant>/sys/module/<driver>/parameter/<option></constant>.
+ The driver can be unconfigured by passing an empty string. You cannot
+ change the configuration while the debugger is attached. Make sure
+ to detach the debugger with the <constant>detach</constant> command
+ prior to trying unconfigure a kgdb I/O driver.
+ </para>
+ <sect1 id="ConnectingGDB">
+ <title>Connecting with gdb to a serial port</title>
<orderedlist>
- <listitem><para>Activate with the kernel command line option:</para>
- <para><constant>kgdbcon</constant></para>
+ <listitem><para>Configure kgdboc</para>
+ <para>Boot kernel with arguments:
+ <itemizedlist>
+ <listitem><para><constant>kgdboc=ttyS0,115200</constant></para></listitem>
+ </itemizedlist></para>
+ <para>OR</para>
+ <para>Configure kgdboc after the kernel booted:
+ <itemizedlist>
+ <listitem><para><constant>echo ttyS0 > /sys/module/kgdboc/parameters/kgdboc</constant></para></listitem>
+ </itemizedlist></para>
</listitem>
- <listitem><para>Use sysfs before configuring an io driver</para>
- <para>
- <constant>echo 1 > /sys/module/kgdb/parameters/kgdb_use_con</constant>
- </para>
- <para>
- NOTE: If you do this after you configure the kgdb I/O driver, the
- setting will not take effect until the next point the I/O is
- reconfigured.
- </para>
+ <listitem>
+ <para>Stop kernel execution (break into the debugger)</para>
+ <para>In order to connect to gdb to the via kgdboc the kernel must
+ first be stopped. There are several ways to stop the kernel which
+ include using kgdbwait as a boot argument, via a sysrq-g, or running
+ the kernel until it takes an an exception where it waits for the
+ debugger to attach.
+ <itemizedlist>
+ <listitem><para>When logged in as root or with a super user session you can run:</para>
+ <para><constant>echo g > /proc/sysrq-trigger</constant></para></listitem>
+ <listitem><para>Example using minicom 2.2</para>
+ <para>Press: <constant>Control-a</constant></para>
+ <para>Press: <constant>f</constant></para>
+ <para>Press: <constant>g</constant></para>
</listitem>
- </orderedlist>
- </para>
- <para>
- IMPORTANT NOTE: Using this option with kgdb over the console
- (kgdboc) is not supported.
+ <listitem><para>When you have telneted to a terminal server that supports sending a remote break</para>
+ <para>Press: <constant>Control-]</constant></para>
+ <para>Type in:<constant>send break</constant></para>
+ <para>Press: <constant>Enter</constant></para>
+ <para>Press: <constant>g</constant></para>
+ </listitem>
+ </itemizedlist>
</para>
- </sect1>
- </chapter>
- <chapter id="ConnectingGDB">
- <title>Connecting gdb</title>
- <para>
- If you are using kgdboc, you need to have used kgdbwait as a boot
- argument, issued a sysrq-g, or the system you are going to debug
- has already taken an exception and is waiting for the debugger to
- attach before you can connect gdb.
- </para>
- <para>
- If you are not using different kgdb I/O driver other than kgdboc,
- you should be able to connect and the target will automatically
- respond.
- </para>
+ </listitem>
+ <listitem>
+ <para>Connect from from gdb</para>
<para>
- Example (using a serial port):
+ Example (using a directly connected port):
</para>
<programlisting>
% gdb ./vmlinux
@@ -283,6 +494,82 @@
communications. You do this prior to issuing the <constant>target
remote</constant> command by typing in: <constant>set debug remote 1</constant>
</para>
+ </listitem>
+ </orderedlist>
+ <para>Remember if you continue in gdb, and need "break in" again,
+ you need to issue an other sysrq. It is easy to create an simple
+ entry point by putting a breakpoint at <constant>sys_sync</constant>
+ and then you can run "sync" from a shell or script to break into the
+ debugger.</para>
+ </sect1>
+ </chapter>
+ <chapter id="switchKdbKgdb">
+ <title>kgdb and kdb interoperability</title>
+ <para>It is possible to transition between kdb and kgdb dynamically.
+ The debug core will remember which you used the last time and
+ automatically start in the same mode.</para>
+ <sect1>
+ <title>Switching between kdb and kgdb</title>
+ <sect2>
+ <title>Switching from kgdb to kdb</title>
+ <para>
+ There are two ways to switch from kgdb to kdb, you can use gdb to
+ issue a maintenance packet, or you can blindly type the command $3#33.
+ When ever kernel debugger stops in kgdb mode it will print the
+ message <constant>KGDB or $3#33 for KDB</constant>. It is important
+ to note, that you have to type the sequence correctly in one pass.
+ You cannot type a backspace or delete because kgdb will interpret
+ that as part of the debug stream.
+ <orderedlist>
+ <listitem><para>Change from kgdb to kdb by blindly typing:</para>
+ <para><constant>$3#33</constant></para></listitem>
+ <listitem><para>Change from kgdb to kdb with gdb</para>
+ <para><constant>maintenance packet 3</constant></para>
+ <para>NOTE: Now you must kill gdb</para></listitem>
+ </orderedlist>
+ </para>
+ </sect2>
+ <sect2>
+ <title>Change from kdb to kgdb</title>
+ <para>There are two ways you can change from kdb to kgdb. You can
+ manually enter kgdb mode by issuing the kgdb command from the kdb
+ shell prompt, or you can connect gdb while the kdb shell prompt is
+ active. The kdb shell looks for the typical first commands that gdb
+ would issue with the gdb remote protocol and if it sees one of those
+ commands it automatically changes into kgdb mode.</para>
+ <orderedlist>
+ <listitem><para>From kdb issue the command:</para>
+ <para><constant>kgdb</constant></para>
+ <para>Now disconnect your terminal program and connect gdb in its place</para></listitem>
+ <listitem><para>At the kdb prompt, disconnect the terminal program and connect gdb in its place.</para></listitem>
+ </orderedlist>
+ </sect2>
+ </sect1>
+ <sect1>
+ <title>Running kdb commands from gdb</title>
+ <para>It is possible to run a limited set of kdb commands from gdb,
+ using the gdb monitor command. You don't want to execute any of the
+ run control or breakpoint operations, because it can disrupt the
+ state of the kernel debugger. You should be using gdb for
+ breakpoints and run control operations if you have gdb connected.
+ The more useful commands to run are things like lsmod, dmesg, ps or
+ possibly some of the memory information. To see all the kdb
+ commands you can run <constant>monitor help</constant>.</para>
+ <para>Example:
+ <informalexample><programlisting>
+(gdb) monitor ps
+1 idle process (state I) and
+27 sleeping system daemon (state M) processes suppressed,
+use 'ps A' to see all.
+Task Addr Pid Parent [*] cpu State Thread Command
+
+0xc78291d0 1 0 0 0 S 0xc7829404 init
+0xc7954150 942 1 0 0 S 0xc7954384 dropbear
+0xc78789c0 944 1 0 0 S 0xc7878bf4 sh
+(gdb)
+ </programlisting></informalexample>
+ </para>
+ </sect1>
</chapter>
<chapter id="KGDBTestSuite">
<title>kgdb Test Suite</title>
@@ -309,22 +596,22 @@
</para>
</chapter>
<chapter id="CommonBackEndReq">
- <title>KGDB Internals</title>
+ <title>Kernel Debugger Internals</title>
<sect1 id="kgdbArchitecture">
<title>Architecture Specifics</title>
<para>
- Kgdb is organized into three basic components:
+ The kernel debugger is organized into a number of components:
<orderedlist>
- <listitem><para>kgdb core</para>
+ <listitem><para>The debug core</para>
<para>
- The kgdb core is found in kernel/kgdb.c. It contains:
+ The debug core is found in kernel/debugger/debug_core.c. It contains:
<itemizedlist>
- <listitem><para>All the logic to implement the gdb serial protocol</para></listitem>
<listitem><para>A generic OS exception handler which includes sync'ing the processors into a stopped state on an multi cpu system.</para></listitem>
<listitem><para>The API to talk to the kgdb I/O drivers</para></listitem>
<listitem><para>The API to make calls to the arch specific kgdb implementation</para></listitem>
<listitem><para>The logic to perform safe memory reads and writes to memory while using the debugger</para></listitem>
<listitem><para>A full implementation for software breakpoints unless overridden by the arch</para></listitem>
+ <listitem><para>The API to invoke either the kdb or kgdb frontend to the debug core.</para></listitem>
</itemizedlist>
</para>
</listitem>
@@ -347,9 +634,30 @@
</itemizedlist>
</para>
</listitem>
+ <listitem><para>gdbstub frontend (aka kgdb)</para>
+ <para>The gdbstub is located in kernel/debug/gdbstub.c. It contains:</para>
+ <itemizedlist>
+ <listitem><para>All the logic to implement the gdb serial protocol</para></listitem>
+ </itemizedlist>
+ </listitem>
+ <listitem><para>kdb frontend</para>
+ <para>The kdb debugger shell is broken down into a number of
+ components. The kdb core is located in kernel/debug/kdb. There
+ are number of helper functions in some of the other kernel
+ components to make it possible for kdb to examine report
+ information about the kernel without taking locks that could
+ cause a kernel deadlock. The kdb core contains implements the following functionality.</para>
+ <itemizedlist>
+ <listitem><para>A simple shell</para></listitem>
+ <listitem><para>The kdb core command set</para></listitem>
+ <listitem><para>A registration API to register additional kdb shell commands.</para></listitem>
+ <listitem><para>The implementation for kdb_printf() which emit messages directly to I/O drivers, bypassing the kernel log.</para></listitem>
+ <listitem><para>SW / HW breakpoint management for the kdb shell</para></listitem>
+ </itemizedlist>
+ </listitem>
<listitem><para>kgdb I/O driver</para>
<para>
- Each kgdb I/O driver has to provide an implemenation for the following:
+ Each kgdb I/O driver has to provide an implementation for the following:
<itemizedlist>
<listitem><para>configuration via builtin or module</para></listitem>
<listitem><para>dynamic configuration and kgdb hook registration calls</para></listitem>
@@ -453,6 +761,10 @@
<itemizedlist>
<listitem><para>Jason Wessel<email>jason.wessel@windriver.com</email></para></listitem>
</itemizedlist>
+ In Jan 2010 this document was updated to include kdb.
+ <itemizedlist>
+ <listitem><para>Jason Wessel<email>jason.wessel@windriver.com</email></para></listitem>
+ </itemizedlist>
</para>
</chapter>
</book>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f3be1e6..af8b8e8 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -57,6 +57,7 @@ parameter is applicable:
ISAPNP ISA PnP code is enabled.
ISDN Appropriate ISDN support is enabled.
JOY Appropriate joystick support is enabled.
+ KGDB Kernel debugger support is enabled.
KVM Kernel Virtual Machine support is enabled.
LIBATA Libata driver is enabled
LP Printer support is enabled.
@@ -1102,13 +1103,17 @@ and is between 256 and 4096 characters. It is defined in the file
use the HighMem zone if it exists, and the Normal
zone if it does not.
- kgdboc= [HW] kgdb over consoles.
+ kgdboc= [KGDB,HW] kgdb over consoles.
Requires a tty driver that supports console polling,
or a supported polling keyboard driver (non-usb).
Serial only format: <serial_device>[,baud]
keyboard only format: kbd
keyboard and serial format: kbd,<serial_device>[,baud]
+ kgdbwait [KGDB] Stop kernel execution and enter the
+ kernel debugger at the earliest opportunity if
+ kgdb was configured on as a boot argument.
+
kmac= [MIPS] korina ethernet MAC address.
Configure the RouterBoard 532 series on-chip
Ethernet adapter MAC address.
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 97068ba..33b9f5e 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -204,6 +204,17 @@ kgdb_arch_handle_exception(int vector, int signo, int err_code,
*/
extern void kgdb_roundup_cpus(unsigned long flags);
+/**
+ * kgdb_arch_set_pc - Generic call back to the program counter
+ * @regs: Current &struct pt_regs.
+ * @pc: The new value for the program counter
+ *
+ * This function handles updating the program counter and requires an
+ * architecture specific implementation.
+ */
+extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
+
+
/* Optional functions. */
extern int kgdb_validate_break_address(unsigned long addr);
extern int kgdb_arch_set_breakpoint(unsigned long addr, char *saved_instr);
@@ -264,7 +275,6 @@ extern struct kgdb_arch arch_kgdb_ops;
extern unsigned long __weak kgdb_arch_pc(int exception, struct pt_regs *regs);
-extern void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc);
extern int kgdb_register_io_module(struct kgdb_io *local_kgdb_io_ops);
extern void kgdb_unregister_io_module(struct kgdb_io *local_kgdb_io_ops);
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 0fb633c..c80de7d 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -3,7 +3,7 @@ config HAVE_ARCH_KGDB
bool
menuconfig KGDB
- bool "KGDB: kernel debugging with remote gdb"
+ bool "KGDB: kernel debugger"
depends on HAVE_ARCH_KGDB
depends on DEBUG_KERNEL && EXPERIMENTAL
help
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 18/40] kgdb: remove post_primary_code references
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (16 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 17/40] kgdb,docs: Update the kgdb docs to include kdb Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 19/40] x86,kgdb: Add low level debug hook Jason Wessel
` (22 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Remove all the references to the kgdb_post_primary_code. This
function serves no useful purpose because you can obtain the same
information from the "struct kgdb_state *ks" from with in the
debugger, if for some reason you want the data.
Also remove the unintentional duplicate assignment for ks->ex_vector.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/x86/kernel/kgdb.c | 29 -----------------------------
include/linux/kgdb.h | 14 --------------
kernel/debug/debug_core.c | 8 --------
3 files changed, 0 insertions(+), 51 deletions(-)
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index 135c3ec..ce35f72 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -47,20 +47,8 @@
#include <asm/debugreg.h>
#include <asm/apicdef.h>
#include <asm/system.h>
-
#include <asm/apic.h>
-/*
- * Put the error code here just in case the user cares:
- */
-static int gdb_x86errcode;
-
-/*
- * Likewise, the vector number here (since GDB only gets the signal
- * number through the usual means, and that's not very specific):
- */
-static int gdb_x86vector = -1;
-
/**
* pt_regs_to_gdb_regs - Convert ptrace regs to GDB regs
* @gdb_regs: A pointer to hold the registers in the order GDB wants.
@@ -346,23 +334,6 @@ void kgdb_disable_hw_debug(struct pt_regs *regs)
}
}
-/**
- * kgdb_post_primary_code - Save error vector/code numbers.
- * @regs: Original pt_regs.
- * @e_vector: Original error vector.
- * @err_code: Original error code.
- *
- * This is needed on architectures which support SMP and KGDB.
- * This function is called after all the slave cpus have been put
- * to a know spin state and the primary CPU has control over KGDB.
- */
-void kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
-{
- /* primary processor is completely in the debugger */
- gdb_x86vector = e_vector;
- gdb_x86errcode = err_code;
-}
-
#ifdef CONFIG_SMP
/**
* kgdb_roundup_cpus - Get other CPUs into a holding pattern
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 33b9f5e..a2cfd9f 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -36,20 +36,6 @@ struct pt_regs;
extern int kgdb_skipexception(int exception, struct pt_regs *regs);
/**
- * kgdb_post_primary_code - (optional) Save error vector/code numbers.
- * @regs: Original pt_regs.
- * @e_vector: Original error vector.
- * @err_code: Original error code.
- *
- * This is usually needed on architectures which support SMP and
- * KGDB. This function is called after all the secondary cpus have
- * been put to a know spin state and the primary CPU has control over
- * KGDB.
- */
-extern void kgdb_post_primary_code(struct pt_regs *regs, int e_vector,
- int err_code);
-
-/**
* kgdb_disable_hw_debug - (optional) Disable hardware debugging hook
* @regs: Current &struct pt_regs.
*
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 1281d1d..aefd660 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -201,12 +201,6 @@ int __weak kgdb_skipexception(int exception, struct pt_regs *regs)
return 0;
}
-void __weak
-kgdb_post_primary_code(struct pt_regs *regs, int e_vector, int err_code)
-{
- return;
-}
-
/**
* kgdb_disable_hw_debug - Disable hardware debugging while we in kgdb.
* @regs: Current &struct pt_regs.
@@ -584,7 +578,6 @@ return_normal:
* At this point the primary processor is completely
* in the debugger and all secondary CPUs are quiescent
*/
- kgdb_post_primary_code(ks->linux_regs, ks->ex_vector, ks->err_code);
dbg_deactivate_sw_breakpoints();
kgdb_single_step = 0;
kgdb_contthread = current;
@@ -665,7 +658,6 @@ kgdb_handle_exception(int evector, int signo, int ecode, struct pt_regs *regs)
ks->cpu = raw_smp_processor_id();
ks->ex_vector = evector;
ks->signo = signo;
- ks->ex_vector = evector;
ks->err_code = ecode;
ks->kgdb_usethreadid = 0;
ks->linux_regs = regs;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 19/40] x86,kgdb: Add low level debug hook
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (17 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 18/40] kgdb: remove post_primary_code references Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger Jason Wessel
` (21 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a triple fault is
to have a low level "first opportunity handler" in the int3 exception
handler.
Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.
CC: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/x86/include/asm/kgdb.h | 3 +++
arch/x86/kernel/kgdb.c | 22 +++++++++++++++++++++-
arch/x86/kernel/traps.c | 6 ++++++
include/linux/kgdb.h | 1 +
kernel/debug/debug_core.c | 2 +-
lib/Kconfig.kgdb | 9 +++++++++
6 files changed, 41 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/kgdb.h b/arch/x86/include/asm/kgdb.h
index e6c6c80..006da36 100644
--- a/arch/x86/include/asm/kgdb.h
+++ b/arch/x86/include/asm/kgdb.h
@@ -76,4 +76,7 @@ static inline void arch_kgdb_breakpoint(void)
#define BREAK_INSTR_SIZE 1
#define CACHE_FLUSH_IS_SAFE 1
+extern int kgdb_ll_trap(int cmd, const char *str,
+ struct pt_regs *regs, long err, int trap, int sig);
+
#endif /* _ASM_X86_KGDB_H */
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index ce35f72..f4bf7a5 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -490,7 +490,7 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
return NOTIFY_DONE;
}
- if (kgdb_handle_exception(args->trapnr, args->signr, args->err, regs))
+ if (kgdb_handle_exception(args->trapnr, args->signr, cmd, regs))
return NOTIFY_DONE;
/* Must touch watchdog before return to normal operation */
@@ -498,6 +498,26 @@ static int __kgdb_notify(struct die_args *args, unsigned long cmd)
return NOTIFY_STOP;
}
+#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
+int kgdb_ll_trap(int cmd, const char *str,
+ struct pt_regs *regs, long err, int trap, int sig)
+{
+ struct die_args args = {
+ .regs = regs,
+ .str = str,
+ .err = err,
+ .trapnr = trap,
+ .signr = sig,
+
+ };
+
+ if (!kgdb_io_module_registered)
+ return NOTIFY_DONE;
+
+ return __kgdb_notify(&args, cmd);
+}
+#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
+
static int
kgdb_notify(struct notifier_block *self, unsigned long cmd, void *ptr)
{
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 3339917..6ae2122 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -15,6 +15,7 @@
#include <linux/kprobes.h>
#include <linux/uaccess.h>
#include <linux/kdebug.h>
+#include <linux/kgdb.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ptrace.h>
@@ -460,6 +461,11 @@ void restart_nmi(void)
/* May run on IST stack. */
dotraplinkage void __kprobes do_int3(struct pt_regs *regs, long error_code)
{
+#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
+ if (kgdb_ll_trap(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
+ == NOTIFY_STOP)
+ return;
+#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
#ifdef CONFIG_KPROBES
if (notify_die(DIE_INT3, "int3", regs, error_code, 3, SIGTRAP)
== NOTIFY_STOP)
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index a2cfd9f..e4e9206 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -60,6 +60,7 @@ struct uart_port;
void kgdb_breakpoint(void);
extern int kgdb_connected;
+extern int kgdb_io_module_registered;
extern atomic_t kgdb_setting_breakpoint;
extern atomic_t kgdb_cpu_doing_single_step;
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index aefd660..5ceaa0f 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -65,7 +65,7 @@ int kgdb_connected;
EXPORT_SYMBOL_GPL(kgdb_connected);
/* All the KGDB handlers are installed */
-static int kgdb_io_module_registered;
+int kgdb_io_module_registered;
/* Guard for recursive entry */
static int exception_level;
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index c80de7d..0a0e049 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -57,6 +57,15 @@ config KGDB_TESTS_BOOT_STRING
information about other strings you could use beyond the
default of V1F100.
+config KGDB_LOW_LEVEL_TRAP
+ bool "KGDB: Allow debugging with traps in notifiers"
+ depends on X86
+ default n
+ help
+ This will add an extra call back to kgdb for the breakpoint
+ exception handler on which will will allow kgdb to step
+ through a notify handler.
+
config KGDB_KDB
bool "KGDB_KDB: include kdb frontend for kgdb"
default n
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (18 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 19/40] x86,kgdb: Add low level debug hook Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 17:48 ` Russell King - ARM Linux
2010-01-14 14:59 ` [PATCH 21/40] powerpc,kgdb: Introduce low level trap catching Jason Wessel
` (20 subsequent siblings)
40 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Russell King
Add in a low level hook to catch calls to die() in the debugger.
After the debugger is done, the standard system rules will be in play
for the original exception.
The kdb debugger wants a chance to catch these sorts of exceptions for
analysis.
CC: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/arm/include/asm/kgdb.h | 11 +++++++++++
arch/arm/kernel/kgdb.c | 8 ++++++++
arch/arm/kernel/traps.c | 5 +++++
3 files changed, 24 insertions(+), 0 deletions(-)
diff --git a/arch/arm/include/asm/kgdb.h b/arch/arm/include/asm/kgdb.h
index 67af4b8..17c69ae 100644
--- a/arch/arm/include/asm/kgdb.h
+++ b/arch/arm/include/asm/kgdb.h
@@ -11,6 +11,7 @@
#define __ARM_KGDB_H__
#include <linux/ptrace.h>
+#include <linux/notifier.h>
/*
* GDB assumes that we're a user process being debugged, so
@@ -95,6 +96,16 @@ extern int kgdb_fault_expected;
#define _PC 15
#define _CPSR (GDB_MAX_REGS - 1)
+#ifdef CONFIG_KGDB
+int kgdb_die_hook(int cmd, const char *str, struct pt_regs *regs, int err);
+#else
+static inline int kgdb_die_hook(int cmd, const char *str,
+ struct pt_regs *regs, int err)
+{
+ return NOTIFY_DONE;
+}
+#endif
+
/*
* So that we can denote the end of a frame for tracing,
* in the simple case:
diff --git a/arch/arm/kernel/kgdb.c b/arch/arm/kernel/kgdb.c
index bb17e9b..3c0e5e5 100644
--- a/arch/arm/kernel/kgdb.c
+++ b/arch/arm/kernel/kgdb.c
@@ -10,6 +10,7 @@
* Deepak Saxena <dsaxena@plexity.net>
*/
#include <linux/kgdb.h>
+#include <linux/notifier.h>
#include <asm/traps.h>
/* Make a local copy of the registers passed into the handler (bletch) */
@@ -189,6 +190,13 @@ void kgdb_arch_exit(void)
unregister_undef_hook(&kgdb_compiled_brkpt_hook);
}
+int kgdb_die_hook(int cmd, const char *str, struct pt_regs *regs, int err)
+{
+ if (kgdb_handle_exception(1, err, cmd, regs))
+ return NOTIFY_DONE;
+ return NOTIFY_STOP;
+}
+
/*
* Register our undef instruction hooks with ARM undef core.
* We regsiter a hook specifically looking for the KGB break inst
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 3f361a7..707e824 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -21,6 +21,9 @@
#include <linux/hardirq.h>
#include <linux/init.h>
#include <linux/uaccess.h>
+#include <linux/kgdb.h>
+#include <linux/kdebug.h>
+#include <linux/notifier.h>
#include <asm/atomic.h>
#include <asm/cacheflush.h>
@@ -254,6 +257,8 @@ NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
{
struct thread_info *thread = current_thread_info();
+ kgdb_die_hook(DIE_OOPS, str, regs, err);
+
oops_enter();
spin_lock_irq(&die_lock);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 21/40] powerpc,kgdb: Introduce low level trap catching
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (19 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace Jason Wessel
` (19 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel
Cc: kgdb-bugreport, mingo, Jason Wessel, Benjamin Herrenschmidt,
Paul Mackerras
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" low level
program_check_exception() handler.
The other change here is to make sure that kgdb_handle_exception() is
called with correct parameters when catching an oops, because kdb
needs to know if the entry was an oops, single step, or breakpoint
exception.
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/powerpc/kernel/kgdb.c | 7 +++++--
arch/powerpc/kernel/traps.c | 7 +++++++
lib/Kconfig.kgdb | 2 +-
3 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/kgdb.c b/arch/powerpc/kernel/kgdb.c
index 7aafcc5..c06fe55 100644
--- a/arch/powerpc/kernel/kgdb.c
+++ b/arch/powerpc/kernel/kgdb.c
@@ -20,6 +20,7 @@
#include <linux/smp.h>
#include <linux/signal.h>
#include <linux/ptrace.h>
+#include <linux/kdebug.h>
#include <asm/current.h>
#include <asm/processor.h>
#include <asm/machdep.h>
@@ -115,7 +116,9 @@ void kgdb_roundup_cpus(unsigned long flags)
/* KGDB functions to use existing PowerPC64 hooks. */
static int kgdb_debugger(struct pt_regs *regs)
{
- return kgdb_handle_exception(0, computeSignal(TRAP(regs)), 0, regs);
+ if (kgdb_handle_exception(1, computeSignal(TRAP(regs)), DIE_OOPS, regs))
+ return 0;
+ return 1;
}
static int kgdb_handle_breakpoint(struct pt_regs *regs)
@@ -123,7 +126,7 @@ static int kgdb_handle_breakpoint(struct pt_regs *regs)
if (user_mode(regs))
return 0;
- if (kgdb_handle_exception(0, SIGTRAP, 0, regs) != 0)
+ if (kgdb_handle_exception(1, SIGTRAP, 0, regs) != 0)
return 0;
if (*(u32 *) (regs->nip) == *(u32 *) (&arch_kgdb_ops.gdb_bpt_instr))
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d069ff8..379104a 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -809,12 +809,19 @@ void __kprobes program_check_exception(struct pt_regs *regs)
return;
}
if (reason & REASON_TRAP) {
+
+#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
+ if (debugger_bpt(regs))
+ return;
+#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
/* trap exception */
if (notify_die(DIE_BPT, "breakpoint", regs, 5, 5, SIGTRAP)
== NOTIFY_STOP)
return;
+#ifndef CONFIG_KGDB_LOW_LEVEL_TRAP
if (debugger_bpt(regs))
return;
+#endif /* ! CONFIG_KGDB_LOW_LEVEL_TRAP */
if (!(regs->msr & MSR_PR) && /* not user-mode */
report_bug(regs->nip, regs) == BUG_TRAP_TYPE_WARN) {
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 0a0e049..2b1601b 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -59,7 +59,7 @@ config KGDB_TESTS_BOOT_STRING
config KGDB_LOW_LEVEL_TRAP
bool "KGDB: Allow debugging with traps in notifiers"
- depends on X86
+ depends on X86 || PPC
default n
help
This will add an extra call back to kgdb for the breakpoint
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (20 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 21/40] powerpc,kgdb: Introduce low level trap catching Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 17:29 ` David Daney
2010-01-14 14:59 ` [PATCH 23/40] kgdb: Add the ability to schedule a breakpoint via a tasklet Jason Wessel
` (18 subsequent siblings)
40 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Ralf Baechle
The only way the debugger can handle a trap in inside rcu_lock,
notify_die, or atomic_notifier_call_chain without a recursive fault is
to have a low level "first opportunity handler" do_trap_or_bp() handler.
Generally this will be something the vast majority of folks will not
need, but for those who need it, it is added as a kernel .config
option called KGDB_LOW_LEVEL_TRAP.
Also added was a die notification for oops such that kdb can catch an
oops for analysis.
There appeared to be no obvious way to pass the struct pt_regs from
the original exception back to the stack back tracer, so a special
case was added to show_stack() for when kdb is active because you
generally desire to generally look at the back trace of the original
exception.
CC: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
arch/mips/include/asm/kgdb.h | 2 ++
arch/mips/kernel/kgdb.c | 22 +++++++++++++++++++++-
arch/mips/kernel/traps.c | 14 ++++++++++++++
lib/Kconfig.kgdb | 2 +-
4 files changed, 38 insertions(+), 2 deletions(-)
diff --git a/arch/mips/include/asm/kgdb.h b/arch/mips/include/asm/kgdb.h
index 48223b0..19002d6 100644
--- a/arch/mips/include/asm/kgdb.h
+++ b/arch/mips/include/asm/kgdb.h
@@ -38,6 +38,8 @@ extern int kgdb_early_setup;
extern void *saved_vectors[32];
extern void handle_exception(struct pt_regs *regs);
extern void breakinst(void);
+extern int kgdb_ll_trap(int cmd, const char *str,
+ struct pt_regs *regs, long err, int trap, int sig);
#endif /* __KERNEL__ */
diff --git a/arch/mips/kernel/kgdb.c b/arch/mips/kernel/kgdb.c
index 6ed4c83..9b78ff6 100644
--- a/arch/mips/kernel/kgdb.c
+++ b/arch/mips/kernel/kgdb.c
@@ -203,7 +203,7 @@ static int kgdb_mips_notify(struct notifier_block *self, unsigned long cmd,
if (atomic_read(&kgdb_active) != -1)
kgdb_nmicallback(smp_processor_id(), regs);
- if (kgdb_handle_exception(trap, compute_signal(trap), 0, regs))
+ if (kgdb_handle_exception(trap, compute_signal(trap), cmd, regs))
return NOTIFY_DONE;
if (atomic_read(&kgdb_setting_breakpoint))
@@ -217,6 +217,26 @@ static int kgdb_mips_notify(struct notifier_block *self, unsigned long cmd,
return NOTIFY_STOP;
}
+#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
+int kgdb_ll_trap(int cmd, const char *str,
+ struct pt_regs *regs, long err, int trap, int sig)
+{
+ struct die_args args = {
+ .regs = regs,
+ .str = str,
+ .err = err,
+ .trapnr = trap,
+ .signr = sig,
+
+ };
+
+ if (!kgdb_io_module_registered)
+ return NOTIFY_DONE;
+
+ return kgdb_mips_notify(NULL, cmd, &args);
+}
+#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
+
static struct notifier_block kgdb_notifier = {
.notifier_call = kgdb_mips_notify,
};
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 308e434..d42f6a3 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -26,6 +26,8 @@
#include <linux/kgdb.h>
#include <linux/kdebug.h>
#include <linux/notifier.h>
+#include <linux/kdb.h>
+#include "../../../kernel/debug/kdb/kdb_private.h"
#include <asm/bootinfo.h>
#include <asm/branch.h>
@@ -184,6 +186,11 @@ void show_stack(struct task_struct *task, unsigned long *sp)
regs.regs[29] = task->thread.reg29;
regs.regs[31] = 0;
regs.cp0_epc = task->thread.reg31;
+#ifdef CONFIG_KGDB_KDB
+ } else if (atomic_read(&kgdb_active) != -1 &&
+ kdb_current_regs) {
+ memcpy(®s, kdb_current_regs, sizeof(regs));
+#endif /* CONFIG_KGDB_KDB */
} else {
prepare_frametrace(®s);
}
@@ -358,6 +365,8 @@ void __noreturn die(const char * str, const struct pt_regs * regs)
unsigned long dvpret = dvpe();
#endif /* CONFIG_MIPS_MT_SMTC */
+ notify_die(DIE_OOPS, str, (struct pt_regs *)regs, SIGSEGV, 0, 0);
+
console_verbose();
spin_lock_irq(&die_lock);
bust_spinlocks(1);
@@ -698,6 +707,11 @@ static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
siginfo_t info;
char b[40];
+#ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
+ if (kgdb_ll_trap(DIE_TRAP, str, regs, code, 0, 0) == NOTIFY_STOP)
+ return;
+#endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
+
if (notify_die(DIE_TRAP, str, regs, code, 0, 0) == NOTIFY_STOP)
return;
diff --git a/lib/Kconfig.kgdb b/lib/Kconfig.kgdb
index 2b1601b..14b61f4 100644
--- a/lib/Kconfig.kgdb
+++ b/lib/Kconfig.kgdb
@@ -59,7 +59,7 @@ config KGDB_TESTS_BOOT_STRING
config KGDB_LOW_LEVEL_TRAP
bool "KGDB: Allow debugging with traps in notifiers"
- depends on X86 || PPC
+ depends on X86 || PPC || MIPS
default n
help
This will add an extra call back to kgdb for the breakpoint
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 23/40] kgdb: Add the ability to schedule a breakpoint via a tasklet
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (21 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 24/40] kgdboc,kdb: Allow kdb to work on a non open console port Jason Wessel
` (17 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Some kgdb I/O modules require the ability to create a breakpoint
tasklet, such as kgdboc and external modules such as kgdboe. The
breakpoint tasklet is used as an asynchronous entry point into the
debugger which will have a different function scope than the current
execution path where it might not be safe to have an inline
breakpoint. This is true of some of the kgdb I/O drivers which share
code with kgdb and rest of the kernel users.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
include/linux/kgdb.h | 1 +
kernel/debug/debug_core.c | 26 ++++++++++++++++++++++++++
2 files changed, 27 insertions(+), 0 deletions(-)
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index e4e9206..076f3c6 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -270,6 +270,7 @@ extern int kgdb_mem2hex(char *mem, char *buf, int count);
extern int kgdb_hex2mem(char *buf, char *mem, int count);
extern int kgdb_isremovedbreak(unsigned long addr);
+extern void kgdb_schedule_breakpoint(void);
extern int
kgdb_handle_exception(int ex_vector, int signo, int err_code,
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 5ceaa0f..e02c552 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -112,6 +112,7 @@ atomic_t kgdb_active = ATOMIC_INIT(-1);
*/
static atomic_t passive_cpu_wait[NR_CPUS];
static atomic_t cpu_in_kgdb[NR_CPUS];
+static atomic_t kgdb_break_tasklet_var;
atomic_t kgdb_setting_breakpoint;
struct task_struct *kgdb_usethread;
@@ -776,6 +777,31 @@ static void kgdb_unregister_callbacks(void)
}
}
+/*
+ * There are times a tasklet needs to be used vs a compiled in
+ * break point so as to cause an exception outside a kgdb I/O module,
+ * such as is the case with kgdboe, where calling a breakpoint in the
+ * I/O driver itself would be fatal.
+ */
+static void kgdb_tasklet_bpt(unsigned long ing)
+{
+ kgdb_breakpoint();
+ atomic_set(&kgdb_break_tasklet_var, 0);
+}
+
+static DECLARE_TASKLET(kgdb_tasklet_breakpoint, kgdb_tasklet_bpt, 0);
+
+void kgdb_schedule_breakpoint(void)
+{
+ if (atomic_read(&kgdb_break_tasklet_var) ||
+ atomic_read(&kgdb_active) != -1 ||
+ atomic_read(&kgdb_setting_breakpoint))
+ return;
+ atomic_inc(&kgdb_break_tasklet_var);
+ tasklet_schedule(&kgdb_tasklet_breakpoint);
+}
+EXPORT_SYMBOL_GPL(kgdb_schedule_breakpoint);
+
static void kgdb_initial_breakpoint(void)
{
kgdb_break_asap = 0;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 24/40] kgdboc,kdb: Allow kdb to work on a non open console port
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (22 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 23/40] kgdb: Add the ability to schedule a breakpoint via a tasklet Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 25/40] printk,kdb: capture printk() when in kdb shell Jason Wessel
` (16 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
If kdb is open on a serial port that is not actually a console make
sure to call the poll routines to emit and receive characters.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/serial/kgdboc.c | 14 ++++++++++++++
include/linux/kgdb.h | 3 +++
kernel/debug/kdb/kdb_io.c | 16 ++++++++++++++++
3 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index f4066b3..02fbd86 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -16,6 +16,7 @@
#include <linux/kgdb.h>
#include <linux/kdb.h>
#include <linux/tty.h>
+#include <linux/console.h>
#define MAX_CONFIG_LEN 40
@@ -72,12 +73,14 @@ static int configure_kgdboc(void)
int tty_line = 0;
int err;
char *cptr = config;
+ struct console *cons;
err = kgdboc_option_setup(config);
if (err || !strlen(config) || isspace(config[0]))
goto noconfig;
err = -ENODEV;
+ kgdboc_io_ops.is_console = 0;
#ifdef CONFIG_KDB_KEYBOARD
kgdb_tty_driver = NULL;
@@ -98,6 +101,17 @@ static int configure_kgdboc(void)
if (!p)
goto noconfig;
+ cons = console_drivers;
+ while (cons) {
+ int idx;
+ if (cons->device && cons->device(cons, &idx) == p &&
+ idx == tty_line) {
+ kgdboc_io_ops.is_console = 1;
+ break;
+ }
+ cons = cons->next;
+ }
+
kgdb_tty_driver = p;
kgdb_tty_line = tty_line;
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 076f3c6..2d06188 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -247,6 +247,8 @@ struct kgdb_arch {
* the I/O driver.
* @post_exception: Pointer to a function that will do any cleanup work
* for the I/O driver.
+ * @is_console: 1 if the end device is a console 0 if the I/O device is
+ * not a console
*/
struct kgdb_io {
const char *name;
@@ -256,6 +258,7 @@ struct kgdb_io {
int (*init) (void);
void (*pre_exception) (void);
void (*post_exception) (void);
+ int is_console;
};
extern struct kgdb_arch arch_kgdb_ops;
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 8fcd22c..32d5521 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -672,6 +672,14 @@ kdb_printit:
if (!dbg_kdb_mode && kgdb_connected) {
gdbstub_msg_write(kdb_buffer, retlen);
} else {
+ if (!dbg_io_ops->is_console) {
+ len = strlen(kdb_buffer);
+ cp = kdb_buffer;
+ while (len--) {
+ dbg_io_ops->write_char(*cp);
+ cp++;
+ }
+ }
while (c) {
c->write(c, kdb_buffer, retlen);
touch_nmi_watchdog();
@@ -718,6 +726,14 @@ kdb_printit:
kdb_input_flush();
c = console_drivers;
+ if (!dbg_io_ops->is_console) {
+ len = strlen(moreprompt);
+ cp = moreprompt;
+ while (len--) {
+ dbg_io_ops->write_char(*cp);
+ cp++;
+ }
+ }
while (c) {
c->write(c, moreprompt, strlen(moreprompt));
touch_nmi_watchdog();
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 25/40] printk,kdb: capture printk() when in kdb shell
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (23 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 24/40] kgdboc,kdb: Allow kdb to work on a non open console port Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 26/40] keyboard, input: Add hook to input to allow low level event clear Jason Wessel
` (15 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel
Cc: kgdb-bugreport, mingo, Jason Wessel, Randy Dunlap, Andrew Morton
Certain calls from the kdb shell will call out to printk(), and any of
these calls should get vectored back to the kdb_printf() so that the
kdb pager and processing can be used, as well as to properly channel
I/O to the polled I/O devices.
CC: Randy Dunlap <randy.dunlap@oracle.com>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
include/linux/kdb.h | 3 +++
kernel/debug/kdb/kdb_bt.c | 2 ++
kernel/debug/kdb/kdb_io.c | 24 ++++++++++++++++++++----
kernel/debug/kdb/kdb_main.c | 4 ++++
kernel/printk.c | 9 +++++++++
5 files changed, 38 insertions(+), 4 deletions(-)
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index bff071e..118fd49 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -80,6 +80,9 @@ typedef enum {
KDB_REASON_SSTEP, /* Single Step trap. - regs valid */
} kdb_reason_t;
+extern int kdb_trap_printk;
+extern int vkdb_printf(const char *fmt, va_list args)
+ __attribute__ ((format (printf, 1, 0)));
extern int kdb_printf(const char *, ...)
__attribute__ ((format (printf, 1, 2)));
typedef int (*kdb_printf_t)(const char *, ...)
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c
index c73402c..176da1a 100644
--- a/kernel/debug/kdb/kdb_bt.c
+++ b/kernel/debug/kdb/kdb_bt.c
@@ -23,6 +23,7 @@ static void kdb_show_stack(struct task_struct *p, void *addr)
{
int old_lvl = console_loglevel;
console_loglevel = 15;
+ kdb_trap_printk++;
kdb_set_current_task(p);
if (addr) {
show_stack((struct task_struct *)p, addr);
@@ -36,6 +37,7 @@ static void kdb_show_stack(struct task_struct *p, void *addr)
show_stack(p, NULL);
}
console_loglevel = old_lvl;
+ kdb_trap_printk--;
}
/*
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 32d5521..dd75c20 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -29,6 +29,7 @@
#define CMD_BUFLEN 256
char kdb_prompt_str[CMD_BUFLEN];
+int kdb_trap_printk;
static void kgdb_transition_check(char *buffer)
{
@@ -532,12 +533,12 @@ static int kdb_search_string(char *searched, char *searchfor)
return 0;
}
-int kdb_printf(const char *fmt, ...)
+int vkdb_printf(const char *fmt, va_list ap)
{
- va_list ap;
int diag;
int linecount;
int logging, saved_loglevel = 0;
+ int saved_trap_printk;
int got_printf_lock = 0;
int retlen = 0;
int fnd, len;
@@ -548,6 +549,9 @@ int kdb_printf(const char *fmt, ...)
unsigned long uninitialized_var(flags);
preempt_disable();
+ saved_trap_printk = kdb_trap_printk;
+ kdb_trap_printk = 0;
+
/* Serialize kdb_printf if multiple cpus try to write at once.
* But if any cpu goes recursive in kdb, just print the output,
* even if it is interleaved with any other text.
@@ -574,9 +578,7 @@ int kdb_printf(const char *fmt, ...)
next_avail = kdb_buffer;
size_avail = sizeof(kdb_buffer);
}
- va_start(ap, fmt);
vsnprintf(next_avail, size_avail, fmt, ap);
- va_end(ap);
/*
* If kdb_parse() found that the command was cmd xxx | grep yyy
@@ -804,6 +806,20 @@ kdb_print_out:
} else {
__release(kdb_printf_lock);
}
+ kdb_trap_printk = saved_trap_printk;
preempt_enable();
return retlen;
}
+
+int kdb_printf(const char *fmt, ...)
+{
+ va_list ap;
+ int r;
+
+ va_start(ap, fmt);
+ r = vkdb_printf(fmt, ap);
+ va_end(ap);
+
+ return r;
+}
+
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 59bb68d..852e003 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -1056,7 +1056,9 @@ static void kdb_dumpregs(struct pt_regs *regs)
{
int old_lvl = console_loglevel;
console_loglevel = 15;
+ kdb_trap_printk++;
show_regs(regs);
+ kdb_trap_printk--;
kdb_printf("\n");
console_loglevel = old_lvl;
}
@@ -1837,7 +1839,9 @@ static int kdb_sr(int argc, const char **argv)
__sysrq_enabled = 1;
}
+ kdb_trap_printk++;
handle_sysrq(*argv[1], NULL);
+ kdb_trap_printk--;
return 0;
}
diff --git a/kernel/printk.c b/kernel/printk.c
index 9bee02e..cd17a79 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -33,6 +33,7 @@
#include <linux/bootmem.h>
#include <linux/syscalls.h>
#include <linux/kexec.h>
+#include <linux/kdb.h>
#include <linux/ratelimit.h>
#include <linux/kmsg_dump.h>
@@ -609,6 +610,14 @@ asmlinkage int printk(const char *fmt, ...)
va_list args;
int r;
+#ifdef CONFIG_KGDB_KDB
+ if (unlikely(kdb_trap_printk)) {
+ va_start(args, fmt);
+ r = vkdb_printf(fmt, args);
+ va_end(args);
+ return r;
+ }
+#endif
va_start(args, fmt);
r = vprintk(fmt, args);
va_end(args);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 26/40] keyboard, input: Add hook to input to allow low level event clear
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (24 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 25/40] printk,kdb: capture printk() when in kdb shell Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 27/40] debug_core,kdb: Allow the debug core to process a recursive debug entry Jason Wessel
` (14 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Dmitry Torokhov
When using a keyboard with kdb, on resuming the system there needs to
be a hook to allow for the keyboard state to get reset.
This is mainly because there is no way to force the end user to hold
down the original keys that were pressed prior to entering kdb.
CC: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/char/keyboard.c | 30 +++++++++++++++++++++++++-----
drivers/input/input.c | 15 +++++++++++++++
drivers/serial/kgdboc.c | 9 +++++++++
include/linux/input.h | 10 ++++++++++
4 files changed, 59 insertions(+), 5 deletions(-)
diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index f706b1d..1db54f6 100644
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c
@@ -1195,6 +1195,11 @@ static void kbd_keycode(unsigned int keycode, int down, int hw_raw)
if (keycode < BTN_MISC && printk_ratelimit())
printk(KERN_WARNING "keyboard.c: can't emulate rawmode for keycode %d\n", keycode);
+ if (down)
+ set_bit(keycode, key_down);
+ else
+ clear_bit(keycode, key_down);
+
#ifdef CONFIG_MAGIC_SYSRQ /* Handle the SysRq Hack */
if (keycode == KEY_SYSRQ && (sysrq_down || (down == 1 && sysrq_alt))) {
if (!sysrq_down) {
@@ -1237,11 +1242,6 @@ static void kbd_keycode(unsigned int keycode, int down, int hw_raw)
raw_mode = 1;
}
- if (down)
- set_bit(keycode, key_down);
- else
- clear_bit(keycode, key_down);
-
if (rep &&
(!vc_kbd_mode(kbd, VC_REPEAT) ||
(tty && !L_ECHO(tty) && tty_chars_in_buffer(tty)))) {
@@ -1410,6 +1410,23 @@ static const struct input_device_id kbd_ids[] = {
MODULE_DEVICE_TABLE(input, kbd_ids);
+#ifdef CONFIG_KGDB_KDB
+void kbd_clear_keys(void)
+{
+ int i, j, k;
+
+ for (i = 0; i < ARRAY_SIZE(key_down); i++) {
+ k = i * BITS_PER_LONG;
+ for (j = 0; j < BITS_PER_LONG; j++, k++) {
+ if (test_bit(k, key_down)) {
+ kbd_keycode(k, 0, 0);
+ }
+ }
+ }
+}
+#endif
+
+
static struct input_handler kbd_handler = {
.event = kbd_event,
.connect = kbd_connect,
@@ -1417,6 +1434,9 @@ static struct input_handler kbd_handler = {
.start = kbd_start,
.name = "kbd",
.id_table = kbd_ids,
+#ifdef CONFIG_KGDB_KDB
+ .dbg_clear_keys = kbd_clear_keys,
+#endif
};
int __init kbd_init(void)
diff --git a/drivers/input/input.c b/drivers/input/input.c
index ab06071..b530050 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -1635,6 +1635,21 @@ int input_register_handler(struct input_handler *handler)
}
EXPORT_SYMBOL(input_register_handler);
+#ifdef CONFIG_KGDB_KDB
+/* input_db_clear_keys - Clear any keyboards if they have a call back,
+ * after returning from the kernel debugger
+ */
+void input_dbg_clear_keys(void)
+{
+ struct input_handler *handler;
+
+ list_for_each_entry(handler, &input_handler_list, node)
+ if (handler->dbg_clear_keys)
+ handler->dbg_clear_keys();
+}
+EXPORT_SYMBOL_GPL(input_dbg_clear_keys);
+#endif
+
/**
* input_unregister_handler - unregisters an input handler
* @handler: handler to be unregistered
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index 02fbd86..217c9a2 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -17,6 +17,7 @@
#include <linux/kdb.h>
#include <linux/tty.h>
#include <linux/console.h>
+#include <linux/input.h>
#define MAX_CONFIG_LEN 40
@@ -24,6 +25,7 @@ static struct kgdb_io kgdboc_io_ops;
/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
static int configured = -1;
+static int kgdboc_use_kbd; /* 1 if we use a keyboard */
static char config[MAX_CONFIG_LEN];
static struct kparam_string kps = {
@@ -81,6 +83,7 @@ static int configure_kgdboc(void)
err = -ENODEV;
kgdboc_io_ops.is_console = 0;
+ kgdboc_use_kbd = 0;
#ifdef CONFIG_KDB_KEYBOARD
kgdb_tty_driver = NULL;
@@ -89,6 +92,7 @@ static int configure_kgdboc(void)
if (kdb_poll_idx < KDB_POLL_FUNC_MAX) {
kdb_poll_funcs[kdb_poll_idx] = kdb_get_kbd_char;
kdb_poll_idx++;
+ kgdboc_use_kbd = 1;
if (cptr[3] == ',')
cptr += 4;
else
@@ -206,6 +210,11 @@ static void kgdboc_post_exp_handler(void)
/* decrement the module count when the debugger detaches */
if (!kgdb_connected)
module_put(THIS_MODULE);
+#ifdef CONFIG_KDB_KEYBOARD
+ /* If using the kdb keyboard driver release all the keys. */
+ if (kgdboc_use_kbd)
+ input_dbg_clear_keys();
+#endif /* CONFIG_KDB_KEYBOARD */
}
static struct kgdb_io kgdboc_io_ops = {
diff --git a/include/linux/input.h b/include/linux/input.h
index 7be8a65..1e83336 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -1230,6 +1230,9 @@ struct input_handler {
int (*connect)(struct input_handler *handler, struct input_dev *dev, const struct input_device_id *id);
void (*disconnect)(struct input_handle *handle);
void (*start)(struct input_handle *handle);
+#ifdef CONFIG_KGDB_KDB
+ void (*dbg_clear_keys)(void);
+#endif
const struct file_operations *fops;
int minor;
@@ -1315,6 +1318,13 @@ int input_flush_device(struct input_handle* handle, struct file* file);
void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value);
void input_inject_event(struct input_handle *handle, unsigned int type, unsigned int code, int value);
+#ifdef CONFIG_KGDB_KDB
+void input_dbg_clear_keys(void);
+#else
+static inline void input_dbg_clear_keys(void)
+{}
+#endif
+
static inline void input_report_key(struct input_dev *dev, unsigned int code, int value)
{
input_event(dev, EV_KEY, code, !!value);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 27/40] debug_core,kdb: Allow the debug core to process a recursive debug entry
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (25 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 26/40] keyboard, input: Add hook to input to allow low level event clear Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 28/40] kdb,panic,debug_core: Allow the debug core to receive a panic before smp_send_stop() Jason Wessel
` (13 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
This allows kdb to debug a crash with in the kms code with a
single level recursive re-entry.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/debug/debug_core.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index e02c552..344e332 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -443,6 +443,10 @@ static int kgdb_reenter_check(struct kgdb_state *ks)
}
printk(KERN_CRIT "KGDB: re-enter exception: ALL breakpoints killed\n");
+#ifdef CONFIG_KGDB_KDB
+ /* Allow kdb to debug itself one level */
+ return 0;
+#endif
dump_stack();
panic("Recursive entry to debugger");
@@ -487,6 +491,9 @@ acquirelock:
smp_wmb();
atomic_set(&cpu_in_kgdb[cpu], 1);
+ if (exception_level == 1)
+ goto cpu_master_loop;
+
/*
* CPU will loop if it is a slave or request to become a kgdb
* master cpu and acquire the kgdb_active lock:
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 28/40] kdb,panic,debug_core: Allow the debug core to receive a panic before smp_send_stop()
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (26 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 27/40] debug_core,kdb: Allow the debug core to process a recursive debug entry Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 29/40] MAINTAINERS: update kgdb, kdb, and debug_core info Jason Wessel
` (12 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Andrew Morton
It is highly desirable to trap into kdb on panic, and in order
to do so the notifier must be called before smp_send_stop(),
else the debug_core will not be able to correctly trap
all the CPUs.
CC: Ingo Molnar <mingo@elte.hu>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
include/linux/kdb.h | 1 +
kernel/debug/debug_core.c | 19 +++++++++++++++++++
kernel/panic.c | 7 ++++---
3 files changed, 24 insertions(+), 3 deletions(-)
diff --git a/include/linux/kdb.h b/include/linux/kdb.h
index 118fd49..75d8777 100644
--- a/include/linux/kdb.h
+++ b/include/linux/kdb.h
@@ -113,5 +113,6 @@ extern void kdb_si_swapinfo(struct sysinfo *);
#else /* ! CONFIG_KGDB_KDB */
#define KDB_IS_RUNNING() (0)
+#define kdb_printf(...)
#endif /* CONFIG_KGDB_KDB */
#endif /* !_KDB_H */
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 344e332..d755fd1 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -46,6 +46,7 @@
#include <linux/pid.h>
#include <linux/smp.h>
#include <linux/mm.h>
+#include <linux/kdb.h>
#include <asm/cacheflush.h>
#include <asm/byteorder.h>
@@ -749,11 +750,27 @@ static struct sysrq_key_op sysrq_dbg_op = {
};
#endif
+static int kgdb_panic_event(struct notifier_block *self,
+ unsigned long val,
+ void *data)
+{
+ if (dbg_kdb_mode)
+ kdb_printf("PANIC: %s\n", (char *)data);
+ kgdb_breakpoint();
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block kgdb_panic_event_nb = {
+ .notifier_call = kgdb_panic_event,
+};
+
static void kgdb_register_callbacks(void)
{
if (!kgdb_io_module_registered) {
kgdb_io_module_registered = 1;
kgdb_arch_init();
+ atomic_notifier_chain_register(&panic_notifier_list,
+ &kgdb_panic_event_nb);
#ifdef CONFIG_MAGIC_SYSRQ
register_sysrq_key('g', &sysrq_dbg_op);
#endif
@@ -773,6 +790,8 @@ static void kgdb_unregister_callbacks(void)
*/
if (kgdb_io_module_registered) {
kgdb_io_module_registered = 0;
+ atomic_notifier_chain_unregister(&panic_notifier_list,
+ &kgdb_panic_event_nb);
kgdb_arch_exit();
#ifdef CONFIG_MAGIC_SYSRQ
unregister_sysrq_key('g', &sysrq_dbg_op);
diff --git a/kernel/panic.c b/kernel/panic.c
index 5827f7b..1f4fb47 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -66,10 +66,13 @@ NORET_TYPE void panic(const char * fmt, ...)
*/
preempt_disable();
- bust_spinlocks(1);
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
+
+ atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
+
+ bust_spinlocks(1);
printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
#ifdef CONFIG_DEBUG_BUGVERBOSE
dump_stack();
@@ -90,8 +93,6 @@ NORET_TYPE void panic(const char * fmt, ...)
*/
smp_send_stop();
- atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
-
bust_spinlocks(0);
if (!panic_blink)
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 29/40] MAINTAINERS: update kgdb, kdb, and debug_core info
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (27 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 28/40] kdb,panic,debug_core: Allow the debug core to receive a panic before smp_send_stop() Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 30/40] kgdboc,debug_core: Add call backs to allow kernel mode switching Jason Wessel
` (11 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Update the maintained files sections.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
MAINTAINERS | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index c8f47bf..88f4741 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3174,15 +3174,17 @@ S: Maintained
F: include/linux/kexec.h
F: kernel/kexec.c
-KGDB
+KGDB / KDB / debug_core
M: Jason Wessel <jason.wessel@windriver.com>
L: kgdb-bugreport@lists.sourceforge.net
S: Maintained
F: Documentation/DocBook/kgdb.tmpl
+F: drivers/char/kdb_keyboard.*
F: drivers/misc/kgdbts.c
F: drivers/serial/kgdboc.c
F: include/linux/kgdb.h
-F: kernel/kgdb.c
+F: include/linux/kdb.h
+F: kernel/debug/
KMEMCHECK
M: Vegard Nossum <vegardno@ifi.uio.no>
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 30/40] kgdboc,debug_core: Add call backs to allow kernel mode switching
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (28 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 29/40] MAINTAINERS: update kgdb, kdb, and debug_core info Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 31/40] kgdb: add ops arg to kgdb console active & restore hooks Jason Wessel
` (10 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Jesse Barnes
Hooks for the kgdb core for registration of the drm layer to provide a
call backs so as to perform kernel mode switching, for use with kdb.
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/serial/kgdboc.c | 15 +++++++++++++++
include/linux/kgdb.h | 10 ++++++++++
kernel/debug/debug_core.c | 23 +++++++++++++++++++++++
3 files changed, 48 insertions(+), 0 deletions(-)
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index 217c9a2..34b0306 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -26,6 +26,7 @@ static struct kgdb_io kgdboc_io_ops;
/* -1 = init not run yet, 0 = unconfigured, 1 = configured. */
static int configured = -1;
static int kgdboc_use_kbd; /* 1 if we use a keyboard */
+static int kgdboc_use_kms; /* 1 if we use kernel mode switching */
static char config[MAX_CONFIG_LEN];
static struct kparam_string kps = {
@@ -85,6 +86,11 @@ static int configure_kgdboc(void)
kgdboc_io_ops.is_console = 0;
kgdboc_use_kbd = 0;
+ kgdboc_use_kms = 0;
+ if (strncmp(cptr, "kms,", 4) == 0) {
+ cptr += 4;
+ kgdboc_use_kms = 1;
+ }
#ifdef CONFIG_KDB_KEYBOARD
kgdb_tty_driver = NULL;
@@ -200,6 +206,11 @@ static int param_set_kgdboc_var(const char *kmessage, struct kernel_param *kp)
static void kgdboc_pre_exp_handler(void)
{
+ if (kgdboc_use_kms && dbg_kms_console_core &&
+ dbg_kms_console_core->activate_console)
+ if (dbg_kms_console_core->activate_console())
+ printk(KERN_ERR "kgdboc: kernel mode switch error\n");
+
/* Increment the module count when the debugger is active */
if (!kgdb_connected)
try_module_get(THIS_MODULE);
@@ -210,6 +221,10 @@ static void kgdboc_post_exp_handler(void)
/* decrement the module count when the debugger detaches */
if (!kgdb_connected)
module_put(THIS_MODULE);
+ if (kgdboc_use_kms && dbg_kms_console_core &&
+ dbg_kms_console_core->restore_console)
+ if (dbg_kms_console_core->restore_console())
+ printk(KERN_ERR "kgdboc: graphics restore failed\n");
#ifdef CONFIG_KDB_KEYBOARD
/* If using the kdb keyboard driver release all the keys. */
if (kgdboc_use_kbd)
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 2d06188..35ad419 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -286,4 +286,14 @@ extern atomic_t kgdb_active;
extern void __init early_kgdboc_init(void);
#endif /* CONFIG_KGDB_SERIAL_CONSOLE */
#endif /* CONFIG_KGDB */
+
+/* Common to all that include kgdb.h */
+struct dbg_kms_console_ops {
+ int (*activate_console) (void);
+ int (*restore_console) (void);
+};
+
+#ifdef CONFIG_KGDB
+extern struct dbg_kms_console_ops *dbg_kms_console_core;
+#endif
#endif /* _KGDB_H_ */
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index d755fd1..82c7c47 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -781,6 +781,29 @@ static void kgdb_register_callbacks(void)
}
}
+struct dbg_kms_console_ops *dbg_kms_console_core;
+EXPORT_SYMBOL_GPL(dbg_kms_console_core);
+
+int dbg_kms_console_ops_register(struct dbg_kms_console_ops *ops)
+{
+ if (dbg_kms_console_core) {
+ printk(KERN_ERR "dbg_core: KMS ops already in use\n");
+ return -1;
+ }
+ dbg_kms_console_core = ops;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dbg_kms_console_ops_register);
+
+int dbg_kms_console_ops_unregister(struct dbg_kms_console_ops *ops)
+{
+ if (dbg_kms_console_core != ops)
+ printk(KERN_ERR "dbg_core: KMS ops do not match\n");
+ dbg_kms_console_core = NULL;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dbg_kms_console_ops_unregister);
+
static void kgdb_unregister_callbacks(void)
{
/*
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 31/40] kgdb: add ops arg to kgdb console active & restore hooks
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (29 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 30/40] kgdboc,debug_core: Add call backs to allow kernel mode switching Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 32/40] drm: add KGDB/KDB support Add support for KDB entry/exit Jason Wessel
` (9 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jesse Barnes, Jason Wessel
From: Jesse Barnes <jbarnes@virtuousgeek.org>
This allows callers to store the ops structure in a parent device structure.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/serial/kgdboc.c | 4 ++--
include/linux/kgdb.h | 17 ++++++++++++++---
2 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index 34b0306..93b18f9 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -208,7 +208,7 @@ static void kgdboc_pre_exp_handler(void)
{
if (kgdboc_use_kms && dbg_kms_console_core &&
dbg_kms_console_core->activate_console)
- if (dbg_kms_console_core->activate_console())
+ if (dbg_kms_console_core->activate_console(dbg_kms_console_core))
printk(KERN_ERR "kgdboc: kernel mode switch error\n");
/* Increment the module count when the debugger is active */
@@ -223,7 +223,7 @@ static void kgdboc_post_exp_handler(void)
module_put(THIS_MODULE);
if (kgdboc_use_kms && dbg_kms_console_core &&
dbg_kms_console_core->restore_console)
- if (dbg_kms_console_core->restore_console())
+ if (dbg_kms_console_core->restore_console(dbg_kms_console_core))
printk(KERN_ERR "kgdboc: graphics restore failed\n");
#ifdef CONFIG_KDB_KEYBOARD
/* If using the kdb keyboard driver release all the keys. */
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 35ad419..68fa243 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -289,11 +289,22 @@ extern void __init early_kgdboc_init(void);
/* Common to all that include kgdb.h */
struct dbg_kms_console_ops {
- int (*activate_console) (void);
- int (*restore_console) (void);
+ int (*activate_console) (struct dbg_kms_console_ops *ops);
+ int (*restore_console) (struct dbg_kms_console_ops *ops);
};
#ifdef CONFIG_KGDB
extern struct dbg_kms_console_ops *dbg_kms_console_core;
-#endif
+extern int dbg_kms_console_ops_register(struct dbg_kms_console_ops *ops);
+extern int dbg_kms_console_ops_unregister(struct dbg_kms_console_ops *ops);
+#else /* ! CONFIG_KGDB */
+static inline int dbg_kms_console_ops_register(struct dbg_kms_console_ops *ops)
+{
+ return 0;
+}
+static inline int dbg_kms_console_ops_unregister(struct dbg_kms_console_ops *ops)
+{
+ return 0;
+}
+#endif /* ! CONFIG_KGDB */
#endif /* _KGDB_H_ */
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 32/40] drm: add KGDB/KDB support Add support for KDB entry/exit.
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (30 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 31/40] kgdb: add ops arg to kgdb console active & restore hooks Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 33/40] kms,kdb: Force unblank a console device Jason Wessel
` (8 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jesse Barnes
From: Jesse Barnes <jbarnes@virtuousgeek.org>
---
drivers/gpu/drm/drm_fb_helper.c | 79 ++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_display.c | 93 ++++++++++++++++++++++++++++++++++
include/drm/drm_crtc_helper.h | 2 +
include/drm/drm_fb_helper.h | 4 ++
4 files changed, 178 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 1c2b7d4..f65aa4d 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -29,6 +29,7 @@
*/
#include <linux/sysrq.h>
#include <linux/fb.h>
+#include <linux/kgdb.h>
#include "drmP.h"
#include "drm_crtc.h"
#include "drm_fb_helper.h"
@@ -233,6 +234,80 @@ int drm_fb_helper_parse_command_line(struct drm_device *dev)
return 0;
}
+#define to_fb_helper(ops) (container_of((ops), struct drm_fb_helper, kdb_ops))
+
+static int drm_fb_kdb_enter(struct dbg_kms_console_ops *ops)
+{
+ struct drm_fb_helper *helper = to_fb_helper(ops);
+ struct drm_crtc_helper_funcs *funcs;
+ int i;
+
+ if (list_empty(&kernel_fb_helper_list))
+ return false;
+
+ list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
+ for (i = 0; i < helper->crtc_count; i++) {
+ struct drm_mode_set *mode_set =
+ &helper->crtc_info[i].mode_set;
+
+ if (!mode_set->crtc->enabled)
+ continue;
+
+ funcs = mode_set->crtc->helper_private;
+ funcs->mode_set_base_atomic(mode_set->crtc,
+ mode_set->fb,
+ mode_set->x,
+ mode_set->y);
+
+ }
+ }
+
+ return 0;
+}
+
+/* Find the real fb for a given fb helper CRTC */
+static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_crtc *c;
+
+ list_for_each_entry(c, &dev->mode_config.crtc_list, head) {
+ if (crtc->base.id == c->base.id)
+ return c->fb;
+ }
+
+ return NULL;
+}
+
+static int drm_fb_kdb_exit(struct dbg_kms_console_ops *ops)
+{
+ struct drm_fb_helper *helper = to_fb_helper(ops);
+ struct drm_crtc *crtc;
+ struct drm_crtc_helper_funcs *funcs;
+ struct drm_framebuffer *fb;
+ int i;
+
+ for (i = 0; i < helper->crtc_count; i++) {
+ struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
+ crtc = mode_set->crtc;
+ funcs = crtc->helper_private;
+ fb = drm_mode_config_fb(crtc);
+
+ if (!crtc->enabled)
+ continue;
+
+ if (!fb) {
+ DRM_ERROR("no fb to restore??\n");
+ continue;
+ }
+
+ funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
+ crtc->y);
+ }
+
+ return 0;
+}
+
bool drm_fb_helper_force_kernel_mode(void)
{
int i = 0;
@@ -923,6 +998,9 @@ int drm_fb_helper_single_fb_probe(struct drm_device *dev,
/* Switch back to kernel console on panic */
/* multi card linked list maybe */
if (list_empty(&kernel_fb_helper_list)) {
+ fb_helper->kdb_ops.activate_console = drm_fb_kdb_enter;
+ fb_helper->kdb_ops.restore_console = drm_fb_kdb_exit;
+ dbg_kms_console_ops_register(&fb_helper->kdb_ops);
printk(KERN_INFO "registered panic notifier\n");
atomic_notifier_chain_register(&panic_notifier_list,
&paniced);
@@ -937,6 +1015,7 @@ void drm_fb_helper_free(struct drm_fb_helper *helper)
{
list_del(&helper->kernel_fb_list);
if (list_empty(&kernel_fb_helper_list)) {
+ dbg_kms_console_ops_unregister(&helper->kdb_ops);
printk(KERN_INFO "unregistered panic notifier\n");
atomic_notifier_chain_unregister(&panic_notifier_list,
&paniced);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 002612f..d54df76 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1214,6 +1214,98 @@ intel_pin_and_fence_fb_obj(struct drm_device *dev, struct drm_gem_object *obj)
return 0;
}
+/* Assume fb object is pinned & idle & fenced and just update base pointers */
+static int
+intel_pipe_set_base_atomic(struct drm_crtc *crtc, struct drm_framebuffer *fb,
+ int x, int y)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ struct intel_framebuffer *intel_fb;
+ struct drm_i915_gem_object *obj_priv;
+ struct drm_gem_object *obj;
+ int plane = intel_crtc->plane;
+ unsigned long Start, Offset;
+ int dspbase = (plane == 0 ? DSPAADDR : DSPBADDR);
+ int dspsurf = (plane == 0 ? DSPASURF : DSPBSURF);
+ int dspstride = (plane == 0) ? DSPASTRIDE : DSPBSTRIDE;
+ int dsptileoff = (plane == 0 ? DSPATILEOFF : DSPBTILEOFF);
+ int dspcntr_reg = (plane == 0) ? DSPACNTR : DSPBCNTR;
+ u32 dspcntr;
+
+ switch (plane) {
+ case 0:
+ case 1:
+ break;
+ default:
+ DRM_ERROR("Can't update plane %d in SAREA\n", plane);
+ return -EINVAL;
+ }
+
+ intel_fb = to_intel_framebuffer(fb);
+ obj = intel_fb->obj;
+ obj_priv = obj->driver_private;
+
+ dspcntr = I915_READ(dspcntr_reg);
+ /* Mask out pixel format bits in case we change it */
+ dspcntr &= ~DISPPLANE_PIXFORMAT_MASK;
+ switch (fb->bits_per_pixel) {
+ case 8:
+ dspcntr |= DISPPLANE_8BPP;
+ break;
+ case 16:
+ if (fb->depth == 15)
+ dspcntr |= DISPPLANE_15_16BPP;
+ else
+ dspcntr |= DISPPLANE_16BPP;
+ break;
+ case 24:
+ case 32:
+ dspcntr |= DISPPLANE_32BPP_NO_ALPHA;
+ break;
+ default:
+ DRM_ERROR("Unknown color depth\n");
+ return -EINVAL;
+ }
+ if (IS_I965G(dev)) {
+ if (obj_priv->tiling_mode != I915_TILING_NONE)
+ dspcntr |= DISPPLANE_TILED;
+ else
+ dspcntr &= ~DISPPLANE_TILED;
+ }
+
+ if (IS_IRONLAKE(dev))
+ /* must disable */
+ dspcntr |= DISPPLANE_TRICKLE_FEED_DISABLE;
+
+ I915_WRITE(dspcntr_reg, dspcntr);
+
+ Start = obj_priv->gtt_offset;
+ Offset = y * fb->pitch + x * (fb->bits_per_pixel / 8);
+
+ DRM_DEBUG("Writing base %08lX %08lX %d %d\n", Start, Offset, x, y);
+ I915_WRITE(dspstride, fb->pitch);
+ if (IS_I965G(dev)) {
+ I915_WRITE(dspbase, Offset);
+ I915_READ(dspbase);
+ I915_WRITE(dspsurf, Start);
+ I915_READ(dspsurf);
+ I915_WRITE(dsptileoff, (y << 16) | x);
+ } else {
+ I915_WRITE(dspbase, Start + Offset);
+ I915_READ(dspbase);
+ }
+
+ if ((IS_I965G(dev) || plane == 0))
+ intel_update_fbc(crtc, &crtc->mode);
+
+ intel_wait_for_vblank(dev);
+ intel_increase_pllclock(crtc, true);
+
+ return 0;
+}
+
static int
intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
struct drm_framebuffer *old_fb)
@@ -4145,6 +4237,7 @@ static const struct drm_crtc_helper_funcs intel_helper_funcs = {
.mode_fixup = intel_crtc_mode_fixup,
.mode_set = intel_crtc_mode_set,
.mode_set_base = intel_pipe_set_base,
+ .mode_set_base_atomic = intel_pipe_set_base_atomic,
.prepare = intel_crtc_prepare,
.commit = intel_crtc_commit,
.load_lut = intel_crtc_load_lut,
diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index b29e201..4c12319 100644
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -61,6 +61,8 @@ struct drm_crtc_helper_funcs {
/* Move the crtc on the current fb to the given position *optional* */
int (*mode_set_base)(struct drm_crtc *crtc, int x, int y,
struct drm_framebuffer *old_fb);
+ int (*mode_set_base_atomic)(struct drm_crtc *crtc,
+ struct drm_framebuffer *fb, int x, int y);
/* reload the current crtc LUT */
void (*load_lut)(struct drm_crtc *crtc);
diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index 58c892a..c4f87a5 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -30,6 +30,8 @@
#ifndef DRM_FB_HELPER_H
#define DRM_FB_HELPER_H
+#include <linux/kgdb.h>
+
struct drm_fb_helper_crtc {
uint32_t crtc_id;
struct drm_mode_set mode_set;
@@ -63,8 +65,10 @@ struct drm_fb_helper_connector {
struct drm_fb_helper {
struct drm_framebuffer *fb;
+ struct drm_framebuffer *saved_fb;
struct drm_device *dev;
struct drm_display_mode *mode;
+ struct dbg_kms_console_ops kdb_ops;
int crtc_count;
struct drm_fb_helper_crtc *crtc_info;
struct drm_fb_helper_funcs *funcs;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 33/40] kms,kdb: Force unblank a console device
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (31 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 32/40] drm: add KGDB/KDB support Add support for KDB entry/exit Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 34/40] i915: when kgdb is active display compression should be off Jason Wessel
` (7 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel
Cc: kgdb-bugreport, mingo, Jason Wessel, David Airlie, Jesse Barnes
The kgdboc pre exception handler must atomically save the state of the
existing VC console and activate it, if it is blanked.
Before restoring the kernel to a running state, the kgdboc post
exception handler will restore the state of the VC variables that got
changed while atomic.
Helper macros were added to allow kms code to declare debugger safe
mutexes which can be used so long as the debugger restores the state
before resuming.
CC: David Airlie <airlied@linux.ie>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/serial/kgdboc.c | 26 ++++++++++++----
drivers/video/console/fbcon.c | 7 ++++
include/linux/kgdb.h | 19 ++++++++++++
kernel/debug/Makefile | 1 +
kernel/debug/debug_core.c | 1 +
kernel/debug/kms_hooks.c | 62 +++++++++++++++++++++++++++++++++++++++++
6 files changed, 109 insertions(+), 7 deletions(-)
create mode 100644 kernel/debug/kms_hooks.c
diff --git a/drivers/serial/kgdboc.c b/drivers/serial/kgdboc.c
index 93b18f9..05d1605 100644
--- a/drivers/serial/kgdboc.c
+++ b/drivers/serial/kgdboc.c
@@ -204,13 +204,19 @@ static int param_set_kgdboc_var(const char *kmessage, struct kernel_param *kp)
return configure_kgdboc();
}
+static int dbg_restore_graphics;
+
static void kgdboc_pre_exp_handler(void)
{
- if (kgdboc_use_kms && dbg_kms_console_core &&
- dbg_kms_console_core->activate_console)
- if (dbg_kms_console_core->activate_console(dbg_kms_console_core))
+ if (!dbg_restore_graphics && kgdboc_use_kms && dbg_kms_console_core &&
+ dbg_kms_console_core->activate_console) {
+ if (dbg_kms_console_core->activate_console(dbg_kms_console_core)) {
printk(KERN_ERR "kgdboc: kernel mode switch error\n");
-
+ } else {
+ dbg_restore_graphics = 1;
+ dbg_pre_vt_hook();
+ }
+ }
/* Increment the module count when the debugger is active */
if (!kgdb_connected)
try_module_get(THIS_MODULE);
@@ -222,9 +228,15 @@ static void kgdboc_post_exp_handler(void)
if (!kgdb_connected)
module_put(THIS_MODULE);
if (kgdboc_use_kms && dbg_kms_console_core &&
- dbg_kms_console_core->restore_console)
- if (dbg_kms_console_core->restore_console(dbg_kms_console_core))
- printk(KERN_ERR "kgdboc: graphics restore failed\n");
+ dbg_kms_console_core->restore_console) {
+ if (dbg_restore_graphics) {
+ if (dbg_kms_console_core->restore_console(dbg_kms_console_core))
+ printk(KERN_ERR "kgdboc: graphics restore failed\n");
+ dbg_restore_graphics = 0;
+ dbg_post_vt_hook();
+ }
+ }
+
#ifdef CONFIG_KDB_KEYBOARD
/* If using the kdb keyboard driver release all the keys. */
if (kgdboc_use_kbd)
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 3681c6a..6f2ed5a 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -75,6 +75,7 @@
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/crc32.h> /* For counting font checksums */
+#include <linux/kgdb.h>
#include <asm/fb.h>
#include <asm/irq.h>
#include <asm/system.h>
@@ -2318,6 +2319,12 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch)
}
}
+ if (in_dbg_master()) {
+ if (info->fbops->fb_blank)
+ info->fbops->fb_blank(blank, info);
+ return 0;
+ }
+
if (!fbcon_is_inactive(vc, info)) {
if (ops->blank_state != blank) {
ops->blank_state = blank;
diff --git a/include/linux/kgdb.h b/include/linux/kgdb.h
index 68fa243..df67f05 100644
--- a/include/linux/kgdb.h
+++ b/include/linux/kgdb.h
@@ -288,6 +288,14 @@ extern void __init early_kgdboc_init(void);
#endif /* CONFIG_KGDB */
/* Common to all that include kgdb.h */
+#ifdef CONFIG_VT
+extern void dbg_pre_vt_hook(void);
+extern void dbg_post_vt_hook(void);
+#else /* ! CONFIG_VT */
+#define dbg_pre_vt_hook()
+#define dbg_post_vt_hook()
+#endif /* CONFIG_VT */
+
struct dbg_kms_console_ops {
int (*activate_console) (struct dbg_kms_console_ops *ops);
int (*restore_console) (struct dbg_kms_console_ops *ops);
@@ -297,6 +305,14 @@ struct dbg_kms_console_ops {
extern struct dbg_kms_console_ops *dbg_kms_console_core;
extern int dbg_kms_console_ops_register(struct dbg_kms_console_ops *ops);
extern int dbg_kms_console_ops_unregister(struct dbg_kms_console_ops *ops);
+#define in_dbg_master() \
+ (raw_smp_processor_id() == atomic_read(&kgdb_active))
+#define dbg_safe_mutex_lock(x) \
+ if (!in_dbg_master()) \
+ mutex_lock(x)
+#define dbg_safe_mutex_unlock(x) \
+ if (!in_dbg_master()) \
+ mutex_unlock(x)
#else /* ! CONFIG_KGDB */
static inline int dbg_kms_console_ops_register(struct dbg_kms_console_ops *ops)
{
@@ -306,5 +322,8 @@ static inline int dbg_kms_console_ops_unregister(struct dbg_kms_console_ops *ops
{
return 0;
}
+#define in_dbg_master() (0)
+#define dbg_safe_mutex_lock(x) mutex_lock(x)
+#define dbg_safe_mutex_unlock(x) mutex_unlock(x)
#endif /* ! CONFIG_KGDB */
#endif /* _KGDB_H_ */
diff --git a/kernel/debug/Makefile b/kernel/debug/Makefile
index c72de00..fe342c0 100644
--- a/kernel/debug/Makefile
+++ b/kernel/debug/Makefile
@@ -3,5 +3,6 @@
#
obj-$(CONFIG_KGDB) += debug_core.o gdbstub.o
+obj-$(CONFIG_VT) += kms_hooks.o
obj-$(CONFIG_KGDB_KDB) += kdb/
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 82c7c47..6ca3f7c 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -106,6 +106,7 @@ static struct kgdb_bkpt kgdb_break[KGDB_MAX_BREAKPOINTS] = {
* The CPU# of the active CPU, or -1 if none:
*/
atomic_t kgdb_active = ATOMIC_INIT(-1);
+EXPORT_SYMBOL_GPL(kgdb_active);
/*
* We use NR_CPUs not PERCPU, in case kgdb is used to debug early
diff --git a/kernel/debug/kms_hooks.c b/kernel/debug/kms_hooks.c
new file mode 100644
index 0000000..c56b7ce
--- /dev/null
+++ b/kernel/debug/kms_hooks.c
@@ -0,0 +1,62 @@
+/*
+ * Created by: Jason Wessel <jason.wessel@windriver.com>
+ *
+ * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifdef CONFIG_VT
+#include <linux/kgdb.h>
+#include <linux/console.h>
+#include <linux/vt_kern.h>
+#include <linux/selection.h>
+#include <linux/kdb.h>
+#include "kdb/kdb_private.h"
+
+static int dbg_orig_vc_mode;
+static int saved_fg_con;
+static int saved_last_con;
+static int saved_want_con;
+
+void dbg_pre_vt_hook(void)
+{
+ struct vc_data *vc = vc_cons[fg_console].d;
+ saved_fg_con = fg_console;
+ saved_last_con = last_console;
+ saved_want_con = want_console;
+ dbg_orig_vc_mode = vc->vc_mode;
+ vc->vc_mode = KD_TEXT;
+ console_blanked = 0;
+ vc->vc_sw->con_blank(vc, 0, 1);
+ vc->vc_sw->con_set_palette(vc, color_table);
+#ifdef CONFIG_KGDB_KDB
+ /* Set the initial LINES variable if it is not already set */
+ if (vc->vc_rows < 999) {
+ int linecount;
+ char lns[4];
+ const char *setargs[3] = {
+ "set",
+ "LINES",
+ lns,
+ };
+ if (kdbgetintenv(setargs[0], &linecount)) {
+ snprintf(lns, 4, "%i", vc->vc_rows);
+ kdb_set(2, setargs);
+ }
+ }
+#endif /* CONFIG_KGDB_KDB */
+}
+EXPORT_SYMBOL_GPL(dbg_pre_vt_hook);
+
+void dbg_post_vt_hook(void)
+{
+ fg_console = saved_fg_con;
+ last_console = saved_last_con;
+ want_console = saved_want_con;
+ vc_cons[fg_console].d->vc_mode = dbg_orig_vc_mode;
+}
+EXPORT_SYMBOL_GPL(dbg_post_vt_hook);
+#endif /* CONFIG_VT */
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 34/40] i915: when kgdb is active display compression should be off
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (32 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 33/40] kms,kdb: Force unblank a console device Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 35/40] drm_fb_helper: Preserve capability to use atomic kms Jason Wessel
` (6 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, David Airlie
If the HW compression is left on, the call backs from the HW will
crash the kernel. The only time this code is called is when kernel
mode setting is in use with kgdb and the kdb shell.
The atomic display pipe handler callback will reset everything when
kgdb restores kernel to the run state.
CC: David Airlie <airlied@linux.ie>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/gpu/drm/i915/intel_display.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index d54df76..11beb0f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1146,6 +1146,10 @@ static void intel_update_fbc(struct drm_crtc *crtc,
goto out_disable;
}
+ /* If the kernel debugger is active, always disable compression */
+ if (in_dbg_master())
+ goto out_disable;
+
if (dev_priv->display.fbc_enabled(crtc)) {
/* We can re-enable it in this case, but need to update pitch */
if (fb->pitch > dev_priv->cfb_pitch)
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 35/40] drm_fb_helper: Preserve capability to use atomic kms
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (33 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 34/40] i915: when kgdb is active display compression should be off Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 36/40] drm,i915 - atomic mutex hacks Jason Wessel
` (5 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel
Cc: kgdb-bugreport, mingo, Jason Wessel, David Airlie, Jesse Barnes,
Clemens Ladisch
Commit 5349ef3127c77075ff70b2014f17ae0fbcaaf199 changed logic of when
a pixclock was valid vs invalid.
The atomic kernel mode setting used by the kernel debugger relied upon
the drm_fb_helper_check_var() to always return -EINVAL. Until a
better solution exists, this behavior will be restored.
CC: David Airlie <airlied@linux.ie>
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/gpu/drm/drm_fb_helper.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index f65aa4d..1097a47 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -677,7 +677,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
struct drm_framebuffer *fb = fb_helper->fb;
int depth;
- if (var->pixclock != 0)
+ if (var->pixclock != 0 || in_dbg_master())
return -EINVAL;
/* Need to resize the fb object !!! */
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 36/40] drm,i915 - atomic mutex hacks
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (34 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 35/40] drm_fb_helper: Preserve capability to use atomic kms Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 37/40] kgdb,docs: Update the kgdb docs to include kms Jason Wessel
` (4 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel
Cc: kgdb-bugreport, mingo, Jason Wessel, Jesse Barnes, David Airlie
Here are some hacks to work around mutex crashes in the drm / i915
code.
For now, this is the only way to make the kms / kgdb path safe on an
SMP system.
CC: Jesse Barnes <jbarnes@virtuousgeek.org>
CC: David Airlie <airlied@linux.ie>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
drivers/gpu/drm/drm_fb_helper.c | 12 ++++++------
drivers/gpu/drm/i915/intel_display.c | 17 ++++++++++++-----
2 files changed, 18 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 1097a47..e00301f 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -396,9 +396,9 @@ static void drm_fb_helper_on(struct fb_info *info)
!crtc->enabled)
continue;
- mutex_lock(&dev->mode_config.mutex);
+ dbg_safe_mutex_lock(&dev->mode_config.mutex);
crtc_funcs->dpms(crtc, DRM_MODE_DPMS_ON);
- mutex_unlock(&dev->mode_config.mutex);
+ dbg_safe_mutex_unlock(&dev->mode_config.mutex);
/* Found a CRTC on this fb, now find encoders */
list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
@@ -406,9 +406,9 @@ static void drm_fb_helper_on(struct fb_info *info)
struct drm_encoder_helper_funcs *encoder_funcs;
encoder_funcs = encoder->helper_private;
- mutex_lock(&dev->mode_config.mutex);
+ dbg_safe_mutex_lock(&dev->mode_config.mutex);
encoder_funcs->dpms(encoder, DRM_MODE_DPMS_ON);
- mutex_unlock(&dev->mode_config.mutex);
+ dbg_safe_mutex_unlock(&dev->mode_config.mutex);
}
}
}
@@ -819,9 +819,9 @@ int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
modeset->y = var->yoffset;
if (modeset->num_connectors) {
- mutex_lock(&dev->mode_config.mutex);
+ dbg_safe_mutex_lock(&dev->mode_config.mutex);
ret = crtc->funcs->set_config(modeset);
- mutex_unlock(&dev->mode_config.mutex);
+ dbg_safe_mutex_unlock(&dev->mode_config.mutex);
if (!ret) {
info->var.xoffset = var->xoffset;
info->var.yoffset = var->yoffset;
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 11beb0f..0378840 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -929,6 +929,13 @@ intel_find_pll_g4x_dp(const intel_limit_t *limit, struct drm_crtc *crtc,
void
intel_wait_for_vblank(struct drm_device *dev)
{
+ if (in_dbg_master()) {
+ /* When in the kernel debugger we cannot sleep */
+ preempt_disable();
+ mdelay(20);
+ preempt_enable();
+ return;
+ }
/* Wait for 20ms, i.e. one cycle at 50hz. */
msleep(20);
}
@@ -1351,17 +1358,17 @@ intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
obj = intel_fb->obj;
obj_priv = obj->driver_private;
- mutex_lock(&dev->struct_mutex);
+ dbg_safe_mutex_lock(&dev->struct_mutex);
ret = intel_pin_and_fence_fb_obj(dev, obj);
if (ret != 0) {
- mutex_unlock(&dev->struct_mutex);
+ dbg_safe_mutex_unlock(&dev->struct_mutex);
return ret;
}
ret = i915_gem_object_set_to_gtt_domain(obj, 1);
if (ret != 0) {
i915_gem_object_unpin(obj);
- mutex_unlock(&dev->struct_mutex);
+ dbg_safe_mutex_unlock(&dev->struct_mutex);
return ret;
}
@@ -1388,7 +1395,7 @@ intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
default:
DRM_ERROR("Unknown color depth\n");
i915_gem_object_unpin(obj);
- mutex_unlock(&dev->struct_mutex);
+ dbg_safe_mutex_unlock(&dev->struct_mutex);
return -EINVAL;
}
if (IS_I965G(dev)) {
@@ -1432,7 +1439,7 @@ intel_pipe_set_base(struct drm_crtc *crtc, int x, int y,
}
intel_increase_pllclock(crtc, true);
- mutex_unlock(&dev->struct_mutex);
+ dbg_safe_mutex_unlock(&dev->struct_mutex);
if (!dev->primary->master)
return 0;
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 37/40] kgdb,docs: Update the kgdb docs to include kms
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (35 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 36/40] drm,i915 - atomic mutex hacks Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 38/40] kgdbts,sh: Add in breakpoint pc offset for superh Jason Wessel
` (3 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
Update the kgdb docs to include information about kernel mode setting support.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
Documentation/DocBook/kgdb.tmpl | 82 +++++++++++++++++++++++++++++++----
Documentation/kernel-parameters.txt | 9 +++-
2 files changed, 79 insertions(+), 12 deletions(-)
diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl
index ebae961..bbf4a22 100644
--- a/Documentation/DocBook/kgdb.tmpl
+++ b/Documentation/DocBook/kgdb.tmpl
@@ -200,12 +200,29 @@
only make use of <constant>kgdbwait</constant> and early debugging
if you build kgdboc into the kernel as a builtins.
</para>
+ <para>Optionally you can elect to activate kms (Kernel Mode
+ Setting) integration. When you use kms with kgdboc and you have a
+ video driver that has atomic mode setting hooks, it is possible to
+ enter the debugger on the graphics console. When the kernel
+ execution is resumed, the graphics previous graphics mode will get
+ restored. This integration can serve as a useful tool to aid in
+ dianosing crashes or doing analysis of memory with kdb while
+ allowing the full graphics console applications to run.
+ </para>
<sect2 id="kgdbocArgs">
<title>kgdboc arguments</title>
- <para>Usage: <constant>kgdboc=[kbd][[,]serial_device][,baud]</constant></para>
- <para>You can configure kgdboc to use the keyboard, and or a serial device
- depending on if you are using kdb and or kgdb, in one of the
- following scenarios.
+ <para>Usage: <constant>kgdboc=[kms][[,]kbd][[,]serial_device][,baud]</constant></para>
+ <para>Abreviations:
+ <itemizedlist>
+ <listitem><para>kms = Kernel Mode Setting</para></listitem>
+ <listitem><para>kbd = Keyboard</para></listitem>
+ </itemizedlist>
+ </para>
+ <para>You can configure kgdboc to use the keyboard, and or a serial
+ device depending on if you are using kdb and or kgdb, in one of the
+ following scenarios. The order listed above must be observed if
+ you use any of the optional configurations together. Using kms +
+ only gdb is generally not a usful combination.
<orderedlist>
<listitem><para>kdb and kgdb over only a serial port</para>
<para><constant>kgdboc=<serial_device>[,baud]</constant></para>
@@ -218,6 +235,12 @@
<listitem><para>kdb with a keyboard</para>
<para><constant>kgdboc=kbd</constant></para>
</listitem>
+ <listitem><para>kdb with kernel modesetting</para>
+ <para><constant>kgdboc=kms,kbd</constant></para>
+ </listitem>
+ <listitem><para>kdb with kernel modesetting and kgdb over a serial port</para>
+ <para><constant>kgdboc=kbd,kbd,ttyS0,115200</constant></para>
+ </listitem>
</orderedlist>
</para>
<para>You can configure kgdboc via sysfs or a module or kernel boot line
@@ -612,6 +635,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
<listitem><para>The logic to perform safe memory reads and writes to memory while using the debugger</para></listitem>
<listitem><para>A full implementation for software breakpoints unless overridden by the arch</para></listitem>
<listitem><para>The API to invoke either the kdb or kgdb frontend to the debug core.</para></listitem>
+ <listitem><para>The structures and call back API for atomic kernel mode setting.</para>
+ <para>NOTE: kgdboc is where the kms callbacks are invoked.</para></listitem>
</itemizedlist>
</para>
</listitem>
@@ -719,6 +744,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
</sect1>
<sect1 id="kgdbocDesign">
<title>kgdboc internals</title>
+ <sect2>
+ <title>kgdboc and uarts</title>
<para>
The kgdboc driver is actually a very thin driver that relies on the
underlying low level to the hardware driver having "polling hooks"
@@ -727,10 +754,7 @@ Task Addr Pid Parent [*] cpu State Thread Command
low level uart hook for doing polled mode reading and writing of a
single character while in an atomic context. When kgdb makes an I/O
request to the debugger, kgdboc invokes a call back in the serial
- core which in turn uses the call back in the uart driver. It is
- certainly possible to extend kgdboc to work with non-uart based
- consoles in the future.
- </para>
+ core which in turn uses the call back in the uart driver.</para>
<para>
When using kgdboc with a uart, the uart driver must implement two callbacks in the <constant>struct uart_ops</constant>. Example from drivers/8250.c:<programlisting>
#ifdef CONFIG_CONSOLE_POLL
@@ -744,9 +768,49 @@ Task Addr Pid Parent [*] cpu State Thread Command
that they can be called from an atomic context and have to restore
the state of the uart chip on return such that the system can return
to normal when the debugger detaches. You need to be very careful
- with any kind of lock you consider, because failing here is most
+ with any kind of lock you consider, because failing here is most likely
going to mean pressing the reset button.
</para>
+ </sect2>
+ <sect2 id="kgdbocKbd">
+ <title>kgdboc and keyboards</title>
+ <para>The kgdboc driver contains logic to configure communications
+ with an attached keyboard. The keyboard infrastructure is only
+ compiled into the kernel when CONFIG_KDB_KEYBOARD=y is set in the
+ kernel configuration.</para>
+ <para>The core polled keyboard driver driver for PS/2 type keyboards
+ is in drivers/char/kdb_keyboard.c. This driver is hooked into the
+ debug core when kgdboc populates the callback in the arrary
+ called <constant>kdb_poll_funcs[]</constant>. The
+ kdb_get_kbd_char() is the top level function which polls hardware
+ for single character input.
+ </para>
+ </sect2>
+ <sect2 id="kgdbocKms">
+ <title>kgdboc and kms</title>
+ <para>The kgdboc driver contains logic to request the grpahics
+ display to switch to a text context if you are using
+ kgdboc=kms,... and you have a video driver which has a framebuffer
+ console and atomic kernel mode setting support. Every time kernel
+ debugger is entered it calls kgdboc_pre_exp_handler() which in turn
+ calls dbg_kms_console_core->activate_console(). On resuming kernel
+ execution, the kernel debugger calls kgdboc_post_exp_handler() which
+ in turn calls dbg_kms_console_core->restore_console().</para>
+ <para>Any video driver that wants to be compatible with the kernel
+ debugger and the atomic kms callbacks must implement the
+ mode_set_base_atomic operation. The following is an example from
+ drivers/gpu/drm/i915/intel_display.c:
+ <informalexample>
+ <programlisting>
+static const struct drm_crtc_helper_funcs intel_helper_funcs = {
+[...]
+ .mode_set_base_atomic = intel_pipe_set_base_atomic,
+[...]
+};
+ </programlisting>
+ </informalexample>
+ </para>
+ </sect2>
</sect1>
</chapter>
<chapter id="credits">
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index af8b8e8..b340445 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1106,9 +1106,12 @@ and is between 256 and 4096 characters. It is defined in the file
kgdboc= [KGDB,HW] kgdb over consoles.
Requires a tty driver that supports console polling,
or a supported polling keyboard driver (non-usb).
- Serial only format: <serial_device>[,baud]
- keyboard only format: kbd
- keyboard and serial format: kbd,<serial_device>[,baud]
+ Serial only format: <serial_device>[,baud]
+ keyboard only format: kbd
+ keyboard and serial format: kbd,<serial_device>[,baud]
+ Optional Kernal mode setting:
+ kms, kbd format: kms,kbd
+ kms, kbd and serial format: kms,kbd,<ser_dev>[,baud]
kgdbwait [KGDB] Stop kernel execution and enter the
kernel debugger at the earliest opportunity if
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 38/40] kgdbts,sh: Add in breakpoint pc offset for superh
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (36 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 37/40] kgdb,docs: Update the kgdb docs to include kms Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 39/40] debug_core: Turn off tracing while in the debugger Jason Wessel
` (2 subsequent siblings)
40 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel
The kgdb test suite mimics the behavior of gdb. For the sh
architecture the pc must be decremented by 2 for software breakpoint.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
---
drivers/misc/kgdbts.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)
diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index fcb6ec1..7245023 100644
--- a/drivers/misc/kgdbts.c
+++ b/drivers/misc/kgdbts.c
@@ -295,6 +295,10 @@ static int check_and_rewind_pc(char *put_str, char *arg)
/* On x86 a breakpoint stop requires it to be decremented */
if (addr + 1 == kgdbts_regs.ip)
offset = -1;
+#elif defined(CONFIG_SUPERH)
+ /* On SUPERH a breakpoint stop requires it to be decremented */
+ if (addr + 2 == kgdbts_regs.pc)
+ offset = -2;
#endif
if (strcmp(arg, "silent") &&
instruction_pointer(&kgdbts_regs) + offset != addr) {
@@ -305,6 +309,8 @@ static int check_and_rewind_pc(char *put_str, char *arg)
#ifdef CONFIG_X86
/* On x86 adjust the instruction pointer if needed */
kgdbts_regs.ip += offset;
+#elif defined(CONFIG_SUPERH)
+ kgdbts_regs.pc += offset;
#endif
return 0;
}
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 39/40] debug_core: Turn off tracing while in the debugger
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (37 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 38/40] kgdbts,sh: Add in breakpoint pc offset for superh Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-15 0:10 ` Steven Rostedt
2010-01-14 14:59 ` [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer Jason Wessel
2010-01-30 2:02 ` [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jon Masters
40 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Steven Rostedt
The kernel debugger should turn off kernel tracing any time the
debugger is active and restore it on resume.
CC: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/debug/debug_core.c | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 6ca3f7c..464aa65 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -474,6 +474,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
int sstep_tries = 100;
int error;
int i, cpu;
+ int trace_on = 0;
acquirelock:
/*
* Interrupts will be restored by the 'trap return' code, except when
@@ -518,6 +519,8 @@ return_normal:
*/
if (arch_kgdb_ops.correct_hw_break)
arch_kgdb_ops.correct_hw_break();
+ if (trace_on)
+ tracing_on();
atomic_set(&cpu_in_kgdb[cpu], 0);
touch_softlockup_watchdog_sync();
clocksource_touch_watchdog();
@@ -592,6 +595,9 @@ return_normal:
kgdb_single_step = 0;
kgdb_contthread = current;
exception_level = 0;
+ trace_on = tracing_is_on();
+ if (trace_on)
+ tracing_off();
while (1) {
cpu_master_loop:
@@ -642,6 +648,8 @@ kgdb_restore:
else
kgdb_sstep_pid = 0;
}
+ if (trace_on)
+ tracing_on();
/* Free kgdb_active */
atomic_set(&kgdb_active, -1);
touch_softlockup_watchdog_sync();
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (38 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 39/40] debug_core: Turn off tracing while in the debugger Jason Wessel
@ 2010-01-14 14:59 ` Jason Wessel
2010-01-15 0:14 ` Steven Rostedt
2010-01-30 2:02 ` [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jon Masters
40 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 14:59 UTC (permalink / raw)
To: linux-kernel; +Cc: kgdb-bugreport, mingo, Jason Wessel, Steven Rostedt
Add in a helper function to allow the kdb shell to dump the ftrace
buffer.
CC: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
Documentation/DocBook/kgdb.tmpl | 3 +-
kernel/trace/Makefile | 3 +
kernel/trace/trace.c | 48 +++++++---------
kernel/trace/trace.h | 17 ++++++
kernel/trace/trace_kdb.c | 116 +++++++++++++++++++++++++++++++++++++++
5 files changed, 160 insertions(+), 27 deletions(-)
create mode 100644 kernel/trace/trace_kdb.c
diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl
index bbf4a22..b01b5b1 100644
--- a/Documentation/DocBook/kgdb.tmpl
+++ b/Documentation/DocBook/kgdb.tmpl
@@ -675,7 +675,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
<itemizedlist>
<listitem><para>A simple shell</para></listitem>
<listitem><para>The kdb core command set</para></listitem>
- <listitem><para>A registration API to register additional kdb shell commands.</para></listitem>
+ <listitem><para>A registration API to register additional kdb shell commands.</para>
+ <para>A good example of a self contained kdb module is the "ftdump" command for dumping the ftrace buffer. See: kernel/trace/trace_kdb.c</para></listitem>
<listitem><para>The implementation for kdb_printf() which emit messages directly to I/O drivers, bypassing the kernel log.</para></listitem>
<listitem><para>SW / HW breakpoint management for the kdb shell</para></listitem>
</itemizedlist>
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index cd9ecd8..c48a28f 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -56,5 +56,8 @@ obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o
obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o
obj-$(CONFIG_EVENT_TRACING) += power-traces.o
+ifeq ($(CONFIG_TRACING),y)
+obj-$(CONFIG_KGDB_KDB) += trace_kdb.o
+endif
libftrace-y := ftrace.o
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 0df1b0f..b3c786a 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -100,14 +100,11 @@ static inline void ftrace_enable_cpu(void)
preempt_enable();
}
-static cpumask_var_t __read_mostly tracing_buffer_mask;
+cpumask_var_t __read_mostly tracing_buffer_mask;
/* Define which cpu buffers are currently read in trace_pipe */
static cpumask_var_t tracing_reader_cpumask;
-#define for_each_tracing_cpu(cpu) \
- for_each_cpu(cpu, tracing_buffer_mask)
-
/*
* ftrace_dump_on_oops - variable to dump ftrace buffer on oops
*
@@ -1409,11 +1406,6 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
}
EXPORT_SYMBOL_GPL(trace_vprintk);
-enum trace_file_type {
- TRACE_FILE_LAT_FMT = 1,
- TRACE_FILE_ANNOTATE = 2,
-};
-
static void trace_iterator_increment(struct trace_iterator *iter)
{
/* Don't allow ftrace to trace into the ring buffers */
@@ -1503,7 +1495,7 @@ struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
}
/* Find the next real entry, and increment the iterator to the next entry */
-static void *find_next_entry_inc(struct trace_iterator *iter)
+void *trace_find_next_entry_inc(struct trace_iterator *iter)
{
iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
@@ -1536,12 +1528,12 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
return NULL;
if (iter->idx < 0)
- ent = find_next_entry_inc(iter);
+ ent = trace_find_next_entry_inc(iter);
else
ent = iter;
while (ent && iter->idx < i)
- ent = find_next_entry_inc(iter);
+ ent = trace_find_next_entry_inc(iter);
iter->pos = *pos;
@@ -1878,7 +1870,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
}
-static int trace_empty(struct trace_iterator *iter)
+int trace_empty(struct trace_iterator *iter)
{
int cpu;
@@ -1909,7 +1901,7 @@ static int trace_empty(struct trace_iterator *iter)
}
/* Called with trace_event_read_lock() held. */
-static enum print_line_t print_trace_line(struct trace_iterator *iter)
+enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
@@ -3074,7 +3066,7 @@ waitagain:
iter->pos = -1;
trace_event_read_lock();
- while (find_next_entry_inc(iter) != NULL) {
+ while (trace_find_next_entry_inc(iter) != NULL) {
enum print_line_t ret;
int len = iter->seq.len;
@@ -3156,7 +3148,7 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
if (ret != TRACE_TYPE_NO_CONSUME)
trace_consume(iter);
rem -= count;
- if (!find_next_entry_inc(iter)) {
+ if (!trace_find_next_entry_inc(iter)) {
rem = 0;
iter->ent = NULL;
break;
@@ -3209,7 +3201,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
if (ret <= 0)
goto out_err;
- if (!iter->ent && !find_next_entry_inc(iter)) {
+ if (!iter->ent && !trace_find_next_entry_inc(iter)) {
ret = -EFAULT;
goto out_err;
}
@@ -4262,7 +4254,7 @@ static struct notifier_block trace_die_notifier = {
*/
#define KERN_TRACE KERN_EMERG
-static void
+void
trace_printk_seq(struct trace_seq *s)
{
/* Probably should print a warning here. */
@@ -4277,6 +4269,13 @@ trace_printk_seq(struct trace_seq *s)
trace_seq_init(s);
}
+void trace_init_global_iter(struct trace_iterator *iter)
+{
+ iter->tr = &global_trace;
+ iter->trace = current_trace;
+ iter->cpu_file = TRACE_PIPE_ALL_CPU;
+}
+
static void __ftrace_dump(bool disable_tracing)
{
static arch_spinlock_t ftrace_dump_lock =
@@ -4301,8 +4300,10 @@ static void __ftrace_dump(bool disable_tracing)
if (disable_tracing)
ftrace_kill();
+ trace_init_global_iter(&iter);
+
for_each_tracing_cpu(cpu) {
- atomic_inc(&global_trace.data[cpu]->disabled);
+ atomic_inc(&iter.tr->data[cpu]->disabled);
}
old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
@@ -4312,11 +4313,6 @@ static void __ftrace_dump(bool disable_tracing)
printk(KERN_TRACE "Dumping ftrace buffer:\n");
- /* Simulate the iterator */
- iter.tr = &global_trace;
- iter.trace = current_trace;
- iter.cpu_file = TRACE_PIPE_ALL_CPU;
-
/*
* We need to stop all tracing on all CPUS to read the
* the next buffer. This is a bit expensive, but is
@@ -4338,7 +4334,7 @@ static void __ftrace_dump(bool disable_tracing)
iter.iter_flags |= TRACE_FILE_LAT_FMT;
iter.pos = -1;
- if (find_next_entry_inc(&iter) != NULL) {
+ if (trace_find_next_entry_inc(&iter) != NULL) {
int ret;
ret = print_trace_line(&iter);
@@ -4359,7 +4355,7 @@ static void __ftrace_dump(bool disable_tracing)
trace_flags |= old_userobj;
for_each_tracing_cpu(cpu) {
- atomic_dec(&global_trace.data[cpu]->disabled);
+ atomic_dec(&iter.tr->data[cpu]->disabled);
}
tracing_on();
}
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 4df6a77..563e6f8 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -352,6 +352,12 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
int *ent_cpu, u64 *ent_ts);
+int trace_empty(struct trace_iterator *iter);
+
+void *trace_find_next_entry_inc(struct trace_iterator *iter);
+
+void trace_init_global_iter(struct trace_iterator *iter);
+
void default_wait_pipe(struct trace_iterator *iter);
void poll_wait_pipe(struct trace_iterator *iter);
@@ -391,6 +397,15 @@ void tracing_start_sched_switch_record(void);
int register_tracer(struct tracer *type);
void unregister_tracer(struct tracer *type);
int is_tracing_stopped(void);
+enum trace_file_type {
+ TRACE_FILE_LAT_FMT = 1,
+ TRACE_FILE_ANNOTATE = 2,
+};
+
+extern cpumask_var_t __read_mostly tracing_buffer_mask;
+
+#define for_each_tracing_cpu(cpu) \
+ for_each_cpu(cpu, tracing_buffer_mask)
extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
@@ -483,6 +498,8 @@ trace_array_vprintk(struct trace_array *tr,
unsigned long ip, const char *fmt, va_list args);
int trace_array_printk(struct trace_array *tr,
unsigned long ip, const char *fmt, ...);
+void trace_printk_seq(struct trace_seq *s);
+enum print_line_t print_trace_line(struct trace_iterator *iter);
extern unsigned long trace_flags;
diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
new file mode 100644
index 0000000..9227ff3
--- /dev/null
+++ b/kernel/trace/trace_kdb.c
@@ -0,0 +1,116 @@
+/*
+ * kdb helper for dumping the ftrace buffer
+ *
+ * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com>
+ *
+ * ftrace_dump_buf based on ftrace_dump:
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ */
+#include <linux/init.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/ftrace.h>
+
+#include "../debug/kdb/kdb_private.h"
+#include "trace.h"
+#include "trace_output.h"
+
+static void ftrace_dump_buf(int skip_lines)
+{
+ /* use static because iter can be a bit big for the stack */
+ static struct trace_iterator iter;
+ unsigned int old_userobj;
+ int cnt = 0, cpu;
+
+ trace_init_global_iter(&iter);
+
+ for_each_tracing_cpu(cpu) {
+ atomic_inc(&iter.tr->data[cpu]->disabled);
+ }
+
+ old_userobj = trace_flags;
+
+ /* don't look at user memory in panic mode */
+ trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
+
+ kdb_printf("Dumping ftrace buffer:\n");
+
+ /* reset all but tr, trace, and overruns */
+ memset(&iter.seq, 0,
+ sizeof(struct trace_iterator) -
+ offsetof(struct trace_iterator, seq));
+ iter.iter_flags |= TRACE_FILE_LAT_FMT;
+ iter.pos = -1;
+
+ for_each_tracing_cpu(cpu)
+ iter.buffer_iter[cpu] =
+ ring_buffer_read_start(iter.tr->buffer, cpu);
+
+ if (!trace_empty(&iter))
+ trace_find_next_entry_inc(&iter);
+ while (!trace_empty(&iter)) {
+ if (!cnt)
+ kdb_printf("---------------------------------\n");
+ cnt++;
+
+ if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines)
+ print_trace_line(&iter);
+ if (!skip_lines)
+ trace_printk_seq(&iter.seq);
+ else
+ skip_lines--;
+ if (KDB_FLAG(CMD_INTERRUPT))
+ goto out;
+ }
+
+ if (!cnt)
+ kdb_printf(" (ftrace buffer empty)\n");
+ else
+ kdb_printf("---------------------------------\n");
+
+out:
+ trace_flags = old_userobj;
+
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&iter.tr->data[cpu]->disabled);
+ }
+
+ for_each_tracing_cpu(cpu)
+ if (iter.buffer_iter[cpu])
+ ring_buffer_read_finish(iter.buffer_iter[cpu]);
+}
+
+/*
+ * kdb_ftdump - Dump the ftrace log buffer
+ */
+static int kdb_ftdump(int argc, const char **argv)
+{
+ int skip_lines = 0;
+ char *cp;
+
+ if (argc > 1)
+ return KDB_ARGCOUNT;
+
+ if (argc) {
+ skip_lines = simple_strtol(argv[1], &cp, 0);
+ if (*cp)
+ skip_lines = 0;
+ }
+
+ kdb_trap_printk++;
+ ftrace_dump_buf(skip_lines);
+ kdb_trap_printk--;
+
+ return 0;
+}
+
+static __init int kdb_ftrace_register(void)
+{
+ kdb_register_repeat("ftdump", kdb_ftdump, "", "Dump ftrace log",
+ 0, KDB_REPEAT_NONE);
+ return 0;
+}
+
+late_initcall(kdb_ftrace_register);
--
1.6.3.1.9.g95405b
^ permalink raw reply related [flat|nested] 56+ messages in thread
* Re: [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace
2010-01-14 14:59 ` [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace Jason Wessel
@ 2010-01-14 17:29 ` David Daney
2010-01-14 22:32 ` Jason Wessel
0 siblings, 1 reply; 56+ messages in thread
From: David Daney @ 2010-01-14 17:29 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo, Ralf Baechle
Jason Wessel wrote:
> The only way the debugger can handle a trap in inside rcu_lock,
> notify_die, or atomic_notifier_call_chain without a recursive fault is
> to have a low level "first opportunity handler" do_trap_or_bp() handler.
>
> Generally this will be something the vast majority of folks will not
> need, but for those who need it, it is added as a kernel .config
> option called KGDB_LOW_LEVEL_TRAP.
>
> Also added was a die notification for oops such that kdb can catch an
> oops for analysis.
>
> There appeared to be no obvious way to pass the struct pt_regs from
> the original exception back to the stack back tracer, so a special
> case was added to show_stack() for when kdb is active because you
> generally desire to generally look at the back trace of the original
> exception.
>
> CC: Ralf Baechle <ralf@linux-mips.org>
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> ---
> arch/mips/include/asm/kgdb.h | 2 ++
> arch/mips/kernel/kgdb.c | 22 +++++++++++++++++++++-
> arch/mips/kernel/traps.c | 14 ++++++++++++++
> lib/Kconfig.kgdb | 2 +-
[...]
> +#include "../../../kernel/debug/kdb/kdb_private.h"
>
There must be a better way of referring to this include file. Perhaps
it should be moved to a more central place that is already in the
include path so we can refer to it with #include <.../file.h>
David Daney
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 14:59 ` [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger Jason Wessel
@ 2010-01-14 17:48 ` Russell King - ARM Linux
2010-01-14 18:57 ` Jason Wessel
2010-01-14 20:29 ` Jason Wessel
0 siblings, 2 replies; 56+ messages in thread
From: Russell King - ARM Linux @ 2010-01-14 17:48 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
On Thu, Jan 14, 2010 at 08:59:16AM -0600, Jason Wessel wrote:
> Add in a low level hook to catch calls to die() in the debugger.
>
> After the debugger is done, the standard system rules will be in play
> for the original exception.
>
> The kdb debugger wants a chance to catch these sorts of exceptions for
> analysis.
NAK. I have a similar patch which implements the hook properly - but
with one caveat. It needs a review to ensure that its safe to return
from die(). Until that's established, this patch can not be merged.
Please also ensure that the linux-arm-kernel list is copied with ARM
patches.
diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h
index d65b2f5..5b66e51 100644
--- a/arch/arm/include/asm/system.h
+++ b/arch/arm/include/asm/system.h
@@ -73,8 +73,7 @@ extern unsigned int mem_fclk_21285;
struct pt_regs;
-void die(const char *msg, struct pt_regs *regs, int err)
- __attribute__((noreturn));
+void die(const char *msg, struct pt_regs *regs, int err);
struct siginfo;
void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index f838f36..29a0f4a 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -12,15 +12,17 @@
* 'linux/arch/arm/lib/traps.S'. Mostly a debugging aid, but will probably
* kill the offending process.
*/
-#include <linux/module.h>
#include <linux/signal.h>
-#include <linux/spinlock.h>
#include <linux/personality.h>
#include <linux/kallsyms.h>
-#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
#include <linux/hardirq.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/kexec.h>
+#include <linux/delay.h>
#include <linux/init.h>
-#include <linux/uaccess.h>
#include <asm/atomic.h>
#include <asm/cacheflush.h>
@@ -224,14 +226,21 @@ void show_stack(struct task_struct *tsk, unsigned long *sp)
#define S_SMP ""
#endif
-static void __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs)
+static int __die(const char *str, int err, struct thread_info *thread, struct pt_regs *regs)
{
struct task_struct *tsk = thread->task;
static int die_counter;
+ int ret;
printk(KERN_EMERG "Internal error: %s: %x [#%d]" S_PREEMPT S_SMP "\n",
str, err, ++die_counter);
sysfs_printk_last_file();
+
+ /* trap and error numbers are mostly meaningless on ARM */
+ ret = notify_die(DIE_OOPS, str, regs, err, tsk->thread.trap_no, SIGSEGV);
+ if (ret == NOTIFY_STOP)
+ return ret;
+
print_modules();
__show_regs(regs);
printk(KERN_EMERG "Process %.*s (pid: %d, stack limit = 0x%p)\n",
@@ -243,6 +252,8 @@ static void __die(const char *str, int err, struct thread_info *thread, struct p
dump_backtrace(regs, tsk);
dump_instr(KERN_EMERG, regs);
}
+
+ return ret;
}
DEFINE_SPINLOCK(die_lock);
@@ -250,16 +261,21 @@ DEFINE_SPINLOCK(die_lock);
/*
* This function is protected against re-entrancy.
*/
-NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
+void die(const char *str, struct pt_regs *regs, int err)
{
struct thread_info *thread = current_thread_info();
+ int ret;
oops_enter();
spin_lock_irq(&die_lock);
console_verbose();
bust_spinlocks(1);
- __die(str, err, thread, regs);
+ ret = __die(str, err, thread, regs);
+
+ if (regs && kexec_should_crash(thread->task))
+ crash_kexec(regs);
+
bust_spinlocks(0);
add_taint(TAINT_DIE);
spin_unlock_irq(&die_lock);
@@ -267,11 +283,10 @@ NORET_TYPE void die(const char *str, struct pt_regs *regs, int err)
if (in_interrupt())
panic("Fatal exception in interrupt");
-
if (panic_on_oops)
panic("Fatal exception");
-
- do_exit(SIGSEGV);
+ if (ret != NOTIFY_STOP)
+ do_exit(SIGSEGV);
}
void arm_notify_die(const char *str, struct pt_regs *regs,
^ permalink raw reply related [flat|nested] 56+ messages in thread
* Re: Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 17:48 ` Russell King - ARM Linux
@ 2010-01-14 18:57 ` Jason Wessel
2010-01-14 20:29 ` Jason Wessel
1 sibling, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 18:57 UTC (permalink / raw)
To: Russell King - ARM Linux
Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
Russell King - ARM Linux wrote:
> On Thu, Jan 14, 2010 at 08:59:16AM -0600, Jason Wessel wrote:
>
>> Add in a low level hook to catch calls to die() in the debugger.
>>
>> After the debugger is done, the standard system rules will be in play
>> for the original exception.
>>
>> The kdb debugger wants a chance to catch these sorts of exceptions for
>> analysis.
>>
>
> NAK. I have a similar patch which implements the hook properly - but
> with one caveat. It needs a review to ensure that its safe to return
> from die(). Until that's established, this patch can not be merged.
>
I dropped the patch which you NAK'ed from the series.
As for your included patch, I will try it out against the various
regression tests I have, which exercise the oops and exception paths.
> Please also ensure that the linux-arm-kernel list is copied with ARM
> patches.
>
>
Check.
Thanks,
Jason.
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 17:48 ` Russell King - ARM Linux
2010-01-14 18:57 ` Jason Wessel
@ 2010-01-14 20:29 ` Jason Wessel
2010-01-14 20:46 ` Russell King - ARM Linux
1 sibling, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 20:29 UTC (permalink / raw)
To: Russell King - ARM Linux
Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
Russell King - ARM Linux wrote:
>
> I have a similar patch which implements the hook properly - but
> with one caveat. It needs a review to ensure that its safe to return
> from die(). Until that's established, this patch can not be merged.
>
I completed the analysis on your patch and yes, it is safe to return
from __die() and die() the way you currently structured it, but it
doesn't work quite the same as on some other architectures.
After changing kgdb.c to register with the die notifier, I stepped
through your code with an ICE, as well as running my regression tests
which panic, oops, bad access etc...
While kernel execution does happen to continue to work, I don't know
that you really want to continue execution.
1) The kernel is marked tainted
2) bust_spinlocks() was toggled for a while
On x86 for example, the notifier is invoked prior to the
bust_spinlocks() etc... and then it can pass the exception along to
the rest of the system (which can result in something bad, but
remember the human behind the kernel debugger controls did it for some
reason or another).
I made the following addition to your patch, and then it behaved as
the other archs do with respect to passing along the result of the
exception. Given this information, would you be willing to merge your
patch and possibly fold in the change below, or further comment?
Thanks,
Jason.
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -273,6 +273,9 @@ void die(const char *str, struct pt_regs
bust_spinlocks(1);
ret = __die(str, err, thread, regs);
+ if (ret == NOTIFY_STOP)
+ return;
+
if (regs && kexec_should_crash(thread->task))
crash_kexec(regs);
@@ -285,8 +288,7 @@ void die(const char *str, struct pt_regs
panic("Fatal exception in interrupt");
if (panic_on_oops)
panic("Fatal exception");
- if (ret != NOTIFY_STOP)
- do_exit(SIGSEGV);
+ do_exit(SIGSEGV);
}
void arm_notify_die(const char *str, struct pt_regs *regs,
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 20:29 ` Jason Wessel
@ 2010-01-14 20:46 ` Russell King - ARM Linux
2010-01-18 14:30 ` Jason Wessel
0 siblings, 1 reply; 56+ messages in thread
From: Russell King - ARM Linux @ 2010-01-14 20:46 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
On Thu, Jan 14, 2010 at 02:29:54PM -0600, Jason Wessel wrote:
> Russell King - ARM Linux wrote:
> >
> > I have a similar patch which implements the hook properly - but
> > with one caveat. It needs a review to ensure that its safe to return
> > from die(). Until that's established, this patch can not be merged.
>
> I completed the analysis on your patch and yes, it is safe to return
> from __die() and die() the way you currently structured it, but it
> doesn't work quite the same as on some other architectures.
>
> After changing kgdb.c to register with the die notifier, I stepped
> through your code with an ICE, as well as running my regression tests
> which panic, oops, bad access etc...
>
> While kernel execution does happen to continue to work, I don't know
> that you really want to continue execution.
>
> 1) The kernel is marked tainted
> 2) bust_spinlocks() was toggled for a while
>
> On x86 for example, the notifier is invoked prior to the
> bust_spinlocks() etc... and then it can pass the exception along to
> the rest of the system (which can result in something bad, but
> remember the human behind the kernel debugger controls did it for some
> reason or another).
On x86, it's called in multiple places - both before die(), and also
inside __die().
In __die(), notify_die() gets called with DIE_OOPS. There's also a
pile of notify_die() calls in arch/x86/kernel/traps.c, which we don't
implement on ARM yet - it's unclear what's required here, and until
we have a user of notify_die()...
> I made the following addition to your patch, and then it behaved as
> the other archs do with respect to passing along the result of the
> exception. Given this information, would you be willing to merge your
> patch and possibly fold in the change below, or further comment?
This changes the behaviour away from x86, so I'm not sure it's the
right thing to do. For instance, it means that kexec won't get to
know about the oops on ARM if NOTIFY_STOP is returned, whereas on
x86 it will.
Maybe this hook wasn't meant for kgdb - what does kgdb use on x86?
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace
2010-01-14 17:29 ` David Daney
@ 2010-01-14 22:32 ` Jason Wessel
0 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-14 22:32 UTC (permalink / raw)
To: David Daney; +Cc: linux-kernel, kgdb-bugreport, mingo, Ralf Baechle
David Daney wrote:
> [...]
>
>> +#include "../../../kernel/debug/kdb/kdb_private.h"
>>
>>
>
> There must be a better way of referring to this include file. Perhaps
> it should be moved to a more central place that is already in the
> include path so we can refer to it with #include <.../file.h>
>
I removed the need to include kdb_private.h. The fix will appear in the
kgdb-next branch in the next few days.
Thanks,
Jason.
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 39/40] debug_core: Turn off tracing while in the debugger
2010-01-14 14:59 ` [PATCH 39/40] debug_core: Turn off tracing while in the debugger Jason Wessel
@ 2010-01-15 0:10 ` Steven Rostedt
2010-01-15 14:03 ` Jason Wessel
0 siblings, 1 reply; 56+ messages in thread
From: Steven Rostedt @ 2010-01-15 0:10 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo
On Thu, 2010-01-14 at 08:59 -0600, Jason Wessel wrote:
> The kernel debugger should turn off kernel tracing any time the
> debugger is active and restore it on resume.
>
> CC: Steven Rostedt <rostedt@goodmis.org>
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> ---
> kernel/debug/debug_core.c | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
> index 6ca3f7c..464aa65 100644
> --- a/kernel/debug/debug_core.c
> +++ b/kernel/debug/debug_core.c
> @@ -474,6 +474,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
> int sstep_tries = 100;
> int error;
> int i, cpu;
> + int trace_on = 0;
> acquirelock:
> /*
> * Interrupts will be restored by the 'trap return' code, except when
> @@ -518,6 +519,8 @@ return_normal:
> */
> if (arch_kgdb_ops.correct_hw_break)
> arch_kgdb_ops.correct_hw_break();
> + if (trace_on)
> + tracing_on();
> atomic_set(&cpu_in_kgdb[cpu], 0);
> touch_softlockup_watchdog_sync();
> clocksource_touch_watchdog();
> @@ -592,6 +595,9 @@ return_normal:
> kgdb_single_step = 0;
> kgdb_contthread = current;
> exception_level = 0;
> + trace_on = tracing_is_on();
> + if (trace_on)
> + tracing_off();
Hmm, what happens if tracing gets turned on by something else? Will it
break this code? If so, we may need to do something different here.
-- Steve
>
> while (1) {
> cpu_master_loop:
> @@ -642,6 +648,8 @@ kgdb_restore:
> else
> kgdb_sstep_pid = 0;
> }
> + if (trace_on)
> + tracing_on();
> /* Free kgdb_active */
> atomic_set(&kgdb_active, -1);
> touch_softlockup_watchdog_sync();
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
2010-01-14 14:59 ` [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer Jason Wessel
@ 2010-01-15 0:14 ` Steven Rostedt
2010-01-15 13:15 ` Jason Wessel
0 siblings, 1 reply; 56+ messages in thread
From: Steven Rostedt @ 2010-01-15 0:14 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo
On Thu, 2010-01-14 at 08:59 -0600, Jason Wessel wrote:
> Add in a helper function to allow the kdb shell to dump the ftrace
> buffer.
>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
If this is the final version, I could queue it up in my tree for 34, and
push it off to Ingo.
-- Steve
> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
> ---
> Documentation/DocBook/kgdb.tmpl | 3 +-
> kernel/trace/Makefile | 3 +
> kernel/trace/trace.c | 48 +++++++---------
> kernel/trace/trace.h | 17 ++++++
> kernel/trace/trace_kdb.c | 116 +++++++++++++++++++++++++++++++++++++++
> 5 files changed, 160 insertions(+), 27 deletions(-)
> create mode 100644 kernel/trace/trace_kdb.c
>
> diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl
> index bbf4a22..b01b5b1 100644
> --- a/Documentation/DocBook/kgdb.tmpl
> +++ b/Documentation/DocBook/kgdb.tmpl
> @@ -675,7 +675,8 @@ Task Addr Pid Parent [*] cpu State Thread Command
> <itemizedlist>
> <listitem><para>A simple shell</para></listitem>
> <listitem><para>The kdb core command set</para></listitem>
> - <listitem><para>A registration API to register additional kdb shell commands.</para></listitem>
> + <listitem><para>A registration API to register additional kdb shell commands.</para>
> + <para>A good example of a self contained kdb module is the "ftdump" command for dumping the ftrace buffer. See: kernel/trace/trace_kdb.c</para></listitem>
> <listitem><para>The implementation for kdb_printf() which emit messages directly to I/O drivers, bypassing the kernel log.</para></listitem>
> <listitem><para>SW / HW breakpoint management for the kdb shell</para></listitem>
> </itemizedlist>
> diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
> index cd9ecd8..c48a28f 100644
> --- a/kernel/trace/Makefile
> +++ b/kernel/trace/Makefile
> @@ -56,5 +56,8 @@ obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
> obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o
> obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o
> obj-$(CONFIG_EVENT_TRACING) += power-traces.o
> +ifeq ($(CONFIG_TRACING),y)
> +obj-$(CONFIG_KGDB_KDB) += trace_kdb.o
> +endif
>
> libftrace-y := ftrace.o
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 0df1b0f..b3c786a 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -100,14 +100,11 @@ static inline void ftrace_enable_cpu(void)
> preempt_enable();
> }
>
> -static cpumask_var_t __read_mostly tracing_buffer_mask;
> +cpumask_var_t __read_mostly tracing_buffer_mask;
>
> /* Define which cpu buffers are currently read in trace_pipe */
> static cpumask_var_t tracing_reader_cpumask;
>
> -#define for_each_tracing_cpu(cpu) \
> - for_each_cpu(cpu, tracing_buffer_mask)
> -
> /*
> * ftrace_dump_on_oops - variable to dump ftrace buffer on oops
> *
> @@ -1409,11 +1406,6 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
> }
> EXPORT_SYMBOL_GPL(trace_vprintk);
>
> -enum trace_file_type {
> - TRACE_FILE_LAT_FMT = 1,
> - TRACE_FILE_ANNOTATE = 2,
> -};
> -
> static void trace_iterator_increment(struct trace_iterator *iter)
> {
> /* Don't allow ftrace to trace into the ring buffers */
> @@ -1503,7 +1495,7 @@ struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
> }
>
> /* Find the next real entry, and increment the iterator to the next entry */
> -static void *find_next_entry_inc(struct trace_iterator *iter)
> +void *trace_find_next_entry_inc(struct trace_iterator *iter)
> {
> iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
>
> @@ -1536,12 +1528,12 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
> return NULL;
>
> if (iter->idx < 0)
> - ent = find_next_entry_inc(iter);
> + ent = trace_find_next_entry_inc(iter);
> else
> ent = iter;
>
> while (ent && iter->idx < i)
> - ent = find_next_entry_inc(iter);
> + ent = trace_find_next_entry_inc(iter);
>
> iter->pos = *pos;
>
> @@ -1878,7 +1870,7 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
> return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
> }
>
> -static int trace_empty(struct trace_iterator *iter)
> +int trace_empty(struct trace_iterator *iter)
> {
> int cpu;
>
> @@ -1909,7 +1901,7 @@ static int trace_empty(struct trace_iterator *iter)
> }
>
> /* Called with trace_event_read_lock() held. */
> -static enum print_line_t print_trace_line(struct trace_iterator *iter)
> +enum print_line_t print_trace_line(struct trace_iterator *iter)
> {
> enum print_line_t ret;
>
> @@ -3074,7 +3066,7 @@ waitagain:
> iter->pos = -1;
>
> trace_event_read_lock();
> - while (find_next_entry_inc(iter) != NULL) {
> + while (trace_find_next_entry_inc(iter) != NULL) {
> enum print_line_t ret;
> int len = iter->seq.len;
>
> @@ -3156,7 +3148,7 @@ tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
> if (ret != TRACE_TYPE_NO_CONSUME)
> trace_consume(iter);
> rem -= count;
> - if (!find_next_entry_inc(iter)) {
> + if (!trace_find_next_entry_inc(iter)) {
> rem = 0;
> iter->ent = NULL;
> break;
> @@ -3209,7 +3201,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
> if (ret <= 0)
> goto out_err;
>
> - if (!iter->ent && !find_next_entry_inc(iter)) {
> + if (!iter->ent && !trace_find_next_entry_inc(iter)) {
> ret = -EFAULT;
> goto out_err;
> }
> @@ -4262,7 +4254,7 @@ static struct notifier_block trace_die_notifier = {
> */
> #define KERN_TRACE KERN_EMERG
>
> -static void
> +void
> trace_printk_seq(struct trace_seq *s)
> {
> /* Probably should print a warning here. */
> @@ -4277,6 +4269,13 @@ trace_printk_seq(struct trace_seq *s)
> trace_seq_init(s);
> }
>
> +void trace_init_global_iter(struct trace_iterator *iter)
> +{
> + iter->tr = &global_trace;
> + iter->trace = current_trace;
> + iter->cpu_file = TRACE_PIPE_ALL_CPU;
> +}
> +
> static void __ftrace_dump(bool disable_tracing)
> {
> static arch_spinlock_t ftrace_dump_lock =
> @@ -4301,8 +4300,10 @@ static void __ftrace_dump(bool disable_tracing)
> if (disable_tracing)
> ftrace_kill();
>
> + trace_init_global_iter(&iter);
> +
> for_each_tracing_cpu(cpu) {
> - atomic_inc(&global_trace.data[cpu]->disabled);
> + atomic_inc(&iter.tr->data[cpu]->disabled);
> }
>
> old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
> @@ -4312,11 +4313,6 @@ static void __ftrace_dump(bool disable_tracing)
>
> printk(KERN_TRACE "Dumping ftrace buffer:\n");
>
> - /* Simulate the iterator */
> - iter.tr = &global_trace;
> - iter.trace = current_trace;
> - iter.cpu_file = TRACE_PIPE_ALL_CPU;
> -
> /*
> * We need to stop all tracing on all CPUS to read the
> * the next buffer. This is a bit expensive, but is
> @@ -4338,7 +4334,7 @@ static void __ftrace_dump(bool disable_tracing)
> iter.iter_flags |= TRACE_FILE_LAT_FMT;
> iter.pos = -1;
>
> - if (find_next_entry_inc(&iter) != NULL) {
> + if (trace_find_next_entry_inc(&iter) != NULL) {
> int ret;
>
> ret = print_trace_line(&iter);
> @@ -4359,7 +4355,7 @@ static void __ftrace_dump(bool disable_tracing)
> trace_flags |= old_userobj;
>
> for_each_tracing_cpu(cpu) {
> - atomic_dec(&global_trace.data[cpu]->disabled);
> + atomic_dec(&iter.tr->data[cpu]->disabled);
> }
> tracing_on();
> }
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index 4df6a77..563e6f8 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -352,6 +352,12 @@ struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
> struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
> int *ent_cpu, u64 *ent_ts);
>
> +int trace_empty(struct trace_iterator *iter);
> +
> +void *trace_find_next_entry_inc(struct trace_iterator *iter);
> +
> +void trace_init_global_iter(struct trace_iterator *iter);
> +
> void default_wait_pipe(struct trace_iterator *iter);
> void poll_wait_pipe(struct trace_iterator *iter);
>
> @@ -391,6 +397,15 @@ void tracing_start_sched_switch_record(void);
> int register_tracer(struct tracer *type);
> void unregister_tracer(struct tracer *type);
> int is_tracing_stopped(void);
> +enum trace_file_type {
> + TRACE_FILE_LAT_FMT = 1,
> + TRACE_FILE_ANNOTATE = 2,
> +};
> +
> +extern cpumask_var_t __read_mostly tracing_buffer_mask;
> +
> +#define for_each_tracing_cpu(cpu) \
> + for_each_cpu(cpu, tracing_buffer_mask)
>
> extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
>
> @@ -483,6 +498,8 @@ trace_array_vprintk(struct trace_array *tr,
> unsigned long ip, const char *fmt, va_list args);
> int trace_array_printk(struct trace_array *tr,
> unsigned long ip, const char *fmt, ...);
> +void trace_printk_seq(struct trace_seq *s);
> +enum print_line_t print_trace_line(struct trace_iterator *iter);
>
> extern unsigned long trace_flags;
>
> diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
> new file mode 100644
> index 0000000..9227ff3
> --- /dev/null
> +++ b/kernel/trace/trace_kdb.c
> @@ -0,0 +1,116 @@
> +/*
> + * kdb helper for dumping the ftrace buffer
> + *
> + * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com>
> + *
> + * ftrace_dump_buf based on ftrace_dump:
> + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
> + * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
> + *
> + */
> +#include <linux/init.h>
> +#include <linux/kgdb.h>
> +#include <linux/kdb.h>
> +#include <linux/ftrace.h>
> +
> +#include "../debug/kdb/kdb_private.h"
> +#include "trace.h"
> +#include "trace_output.h"
> +
> +static void ftrace_dump_buf(int skip_lines)
> +{
> + /* use static because iter can be a bit big for the stack */
> + static struct trace_iterator iter;
> + unsigned int old_userobj;
> + int cnt = 0, cpu;
> +
> + trace_init_global_iter(&iter);
> +
> + for_each_tracing_cpu(cpu) {
> + atomic_inc(&iter.tr->data[cpu]->disabled);
> + }
> +
> + old_userobj = trace_flags;
> +
> + /* don't look at user memory in panic mode */
> + trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
> +
> + kdb_printf("Dumping ftrace buffer:\n");
> +
> + /* reset all but tr, trace, and overruns */
> + memset(&iter.seq, 0,
> + sizeof(struct trace_iterator) -
> + offsetof(struct trace_iterator, seq));
> + iter.iter_flags |= TRACE_FILE_LAT_FMT;
> + iter.pos = -1;
> +
> + for_each_tracing_cpu(cpu)
> + iter.buffer_iter[cpu] =
> + ring_buffer_read_start(iter.tr->buffer, cpu);
> +
> + if (!trace_empty(&iter))
> + trace_find_next_entry_inc(&iter);
> + while (!trace_empty(&iter)) {
> + if (!cnt)
> + kdb_printf("---------------------------------\n");
> + cnt++;
> +
> + if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines)
> + print_trace_line(&iter);
> + if (!skip_lines)
> + trace_printk_seq(&iter.seq);
> + else
> + skip_lines--;
> + if (KDB_FLAG(CMD_INTERRUPT))
> + goto out;
> + }
> +
> + if (!cnt)
> + kdb_printf(" (ftrace buffer empty)\n");
> + else
> + kdb_printf("---------------------------------\n");
> +
> +out:
> + trace_flags = old_userobj;
> +
> + for_each_tracing_cpu(cpu) {
> + atomic_dec(&iter.tr->data[cpu]->disabled);
> + }
> +
> + for_each_tracing_cpu(cpu)
> + if (iter.buffer_iter[cpu])
> + ring_buffer_read_finish(iter.buffer_iter[cpu]);
> +}
> +
> +/*
> + * kdb_ftdump - Dump the ftrace log buffer
> + */
> +static int kdb_ftdump(int argc, const char **argv)
> +{
> + int skip_lines = 0;
> + char *cp;
> +
> + if (argc > 1)
> + return KDB_ARGCOUNT;
> +
> + if (argc) {
> + skip_lines = simple_strtol(argv[1], &cp, 0);
> + if (*cp)
> + skip_lines = 0;
> + }
> +
> + kdb_trap_printk++;
> + ftrace_dump_buf(skip_lines);
> + kdb_trap_printk--;
> +
> + return 0;
> +}
> +
> +static __init int kdb_ftrace_register(void)
> +{
> + kdb_register_repeat("ftdump", kdb_ftdump, "", "Dump ftrace log",
> + 0, KDB_REPEAT_NONE);
> + return 0;
> +}
> +
> +late_initcall(kdb_ftrace_register);
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
2010-01-15 0:14 ` Steven Rostedt
@ 2010-01-15 13:15 ` Jason Wessel
0 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-15 13:15 UTC (permalink / raw)
To: rostedt; +Cc: linux-kernel, kgdb-bugreport, mingo
[-- Attachment #1: Type: text/plain, Size: 753 bytes --]
Steven Rostedt wrote:
> On Thu, 2010-01-14 at 08:59 -0600, Jason Wessel wrote:
>
>> Add in a helper function to allow the kdb shell to dump the ftrace
>> buffer.
>>
>>
>
> Acked-by: Steven Rostedt <rostedt@goodmis.org>
>
>
> If this is the final version, I could queue it up in my tree for 34, and
> push it off to Ingo.
>
Attached is the final version. I moved the minor doc update and folded
it into the main docs patch. There are no code changes, and now the
patch should cleanly apply independent of anything else. The patch will
be dropped from kgdb-next as of today.
Please, let me know where the tree lives that contains this patch and I
will continue to pull it into my local testing aimed for merging in 2.6.34.
Thanks,
Jason.
[-- Attachment #2: ftrace_kdb.patch --]
[-- Type: text/x-diff, Size: 9610 bytes --]
From: Jason Wessel <jason.wessel@windriver.com>
Subject: [PATCH] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer
Add in a helper function to allow the kdb shell to dump the ftrace
buffer.
Modify trace.c to expose the capability to iterate over the ftrace
buffer in a read only capacity.
CC: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
kernel/trace/Makefile | 3 +
kernel/trace/trace.c | 48 ++++++++-----------
kernel/trace/trace.h | 17 ++++++
kernel/trace/trace_kdb.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 158 insertions(+), 26 deletions(-)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -100,14 +100,11 @@ static inline void ftrace_enable_cpu(voi
preempt_enable();
}
-static cpumask_var_t __read_mostly tracing_buffer_mask;
+cpumask_var_t __read_mostly tracing_buffer_mask;
/* Define which cpu buffers are currently read in trace_pipe */
static cpumask_var_t tracing_reader_cpumask;
-#define for_each_tracing_cpu(cpu) \
- for_each_cpu(cpu, tracing_buffer_mask)
-
/*
* ftrace_dump_on_oops - variable to dump ftrace buffer on oops
*
@@ -1409,11 +1406,6 @@ int trace_vprintk(unsigned long ip, cons
}
EXPORT_SYMBOL_GPL(trace_vprintk);
-enum trace_file_type {
- TRACE_FILE_LAT_FMT = 1,
- TRACE_FILE_ANNOTATE = 2,
-};
-
static void trace_iterator_increment(struct trace_iterator *iter)
{
/* Don't allow ftrace to trace into the ring buffers */
@@ -1503,7 +1495,7 @@ struct trace_entry *trace_find_next_entr
}
/* Find the next real entry, and increment the iterator to the next entry */
-static void *find_next_entry_inc(struct trace_iterator *iter)
+void *trace_find_next_entry_inc(struct trace_iterator *iter)
{
iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
@@ -1536,12 +1528,12 @@ static void *s_next(struct seq_file *m,
return NULL;
if (iter->idx < 0)
- ent = find_next_entry_inc(iter);
+ ent = trace_find_next_entry_inc(iter);
else
ent = iter;
while (ent && iter->idx < i)
- ent = find_next_entry_inc(iter);
+ ent = trace_find_next_entry_inc(iter);
iter->pos = *pos;
@@ -1878,7 +1870,7 @@ static enum print_line_t print_bin_fmt(s
return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED;
}
-static int trace_empty(struct trace_iterator *iter)
+int trace_empty(struct trace_iterator *iter)
{
int cpu;
@@ -1909,7 +1901,7 @@ static int trace_empty(struct trace_iter
}
/* Called with trace_event_read_lock() held. */
-static enum print_line_t print_trace_line(struct trace_iterator *iter)
+enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
@@ -3074,7 +3066,7 @@ waitagain:
iter->pos = -1;
trace_event_read_lock();
- while (find_next_entry_inc(iter) != NULL) {
+ while (trace_find_next_entry_inc(iter) != NULL) {
enum print_line_t ret;
int len = iter->seq.len;
@@ -3156,7 +3148,7 @@ tracing_fill_pipe_page(size_t rem, struc
if (ret != TRACE_TYPE_NO_CONSUME)
trace_consume(iter);
rem -= count;
- if (!find_next_entry_inc(iter)) {
+ if (!trace_find_next_entry_inc(iter)) {
rem = 0;
iter->ent = NULL;
break;
@@ -3209,7 +3201,7 @@ static ssize_t tracing_splice_read_pipe(
if (ret <= 0)
goto out_err;
- if (!iter->ent && !find_next_entry_inc(iter)) {
+ if (!iter->ent && !trace_find_next_entry_inc(iter)) {
ret = -EFAULT;
goto out_err;
}
@@ -4262,7 +4254,7 @@ static struct notifier_block trace_die_n
*/
#define KERN_TRACE KERN_EMERG
-static void
+void
trace_printk_seq(struct trace_seq *s)
{
/* Probably should print a warning here. */
@@ -4277,6 +4269,13 @@ trace_printk_seq(struct trace_seq *s)
trace_seq_init(s);
}
+void trace_init_global_iter(struct trace_iterator *iter)
+{
+ iter->tr = &global_trace;
+ iter->trace = current_trace;
+ iter->cpu_file = TRACE_PIPE_ALL_CPU;
+}
+
static void __ftrace_dump(bool disable_tracing)
{
static arch_spinlock_t ftrace_dump_lock =
@@ -4301,8 +4300,10 @@ static void __ftrace_dump(bool disable_t
if (disable_tracing)
ftrace_kill();
+ trace_init_global_iter(&iter);
+
for_each_tracing_cpu(cpu) {
- atomic_inc(&global_trace.data[cpu]->disabled);
+ atomic_inc(&iter.tr->data[cpu]->disabled);
}
old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
@@ -4312,11 +4313,6 @@ static void __ftrace_dump(bool disable_t
printk(KERN_TRACE "Dumping ftrace buffer:\n");
- /* Simulate the iterator */
- iter.tr = &global_trace;
- iter.trace = current_trace;
- iter.cpu_file = TRACE_PIPE_ALL_CPU;
-
/*
* We need to stop all tracing on all CPUS to read the
* the next buffer. This is a bit expensive, but is
@@ -4338,7 +4334,7 @@ static void __ftrace_dump(bool disable_t
iter.iter_flags |= TRACE_FILE_LAT_FMT;
iter.pos = -1;
- if (find_next_entry_inc(&iter) != NULL) {
+ if (trace_find_next_entry_inc(&iter) != NULL) {
int ret;
ret = print_trace_line(&iter);
@@ -4359,7 +4355,7 @@ static void __ftrace_dump(bool disable_t
trace_flags |= old_userobj;
for_each_tracing_cpu(cpu) {
- atomic_dec(&global_trace.data[cpu]->disabled);
+ atomic_dec(&iter.tr->data[cpu]->disabled);
}
tracing_on();
}
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -56,5 +56,8 @@ obj-$(CONFIG_EVENT_TRACING) += trace_eve
obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o
obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o
obj-$(CONFIG_EVENT_TRACING) += power-traces.o
+ifeq ($(CONFIG_TRACING),y)
+obj-$(CONFIG_KGDB_KDB) += trace_kdb.o
+endif
libftrace-y := ftrace.o
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -352,6 +352,12 @@ struct trace_entry *tracing_get_trace_en
struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
int *ent_cpu, u64 *ent_ts);
+int trace_empty(struct trace_iterator *iter);
+
+void *trace_find_next_entry_inc(struct trace_iterator *iter);
+
+void trace_init_global_iter(struct trace_iterator *iter);
+
void default_wait_pipe(struct trace_iterator *iter);
void poll_wait_pipe(struct trace_iterator *iter);
@@ -391,6 +397,15 @@ void tracing_start_sched_switch_record(v
int register_tracer(struct tracer *type);
void unregister_tracer(struct tracer *type);
int is_tracing_stopped(void);
+enum trace_file_type {
+ TRACE_FILE_LAT_FMT = 1,
+ TRACE_FILE_ANNOTATE = 2,
+};
+
+extern cpumask_var_t __read_mostly tracing_buffer_mask;
+
+#define for_each_tracing_cpu(cpu) \
+ for_each_cpu(cpu, tracing_buffer_mask)
extern int process_new_ksym_entry(char *ksymname, int op, unsigned long addr);
@@ -483,6 +498,8 @@ trace_array_vprintk(struct trace_array *
unsigned long ip, const char *fmt, va_list args);
int trace_array_printk(struct trace_array *tr,
unsigned long ip, const char *fmt, ...);
+void trace_printk_seq(struct trace_seq *s);
+enum print_line_t print_trace_line(struct trace_iterator *iter);
extern unsigned long trace_flags;
--- /dev/null
+++ b/kernel/trace/trace_kdb.c
@@ -0,0 +1,116 @@
+/*
+ * kdb helper for dumping the ftrace buffer
+ *
+ * Copyright (C) 2010 Jason Wessel <jason.wessel@windriver.com>
+ *
+ * ftrace_dump_buf based on ftrace_dump:
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ */
+#include <linux/init.h>
+#include <linux/kgdb.h>
+#include <linux/kdb.h>
+#include <linux/ftrace.h>
+
+#include "../debug/kdb/kdb_private.h"
+#include "trace.h"
+#include "trace_output.h"
+
+static void ftrace_dump_buf(int skip_lines)
+{
+ /* use static because iter can be a bit big for the stack */
+ static struct trace_iterator iter;
+ unsigned int old_userobj;
+ int cnt = 0, cpu;
+
+ trace_init_global_iter(&iter);
+
+ for_each_tracing_cpu(cpu) {
+ atomic_inc(&iter.tr->data[cpu]->disabled);
+ }
+
+ old_userobj = trace_flags;
+
+ /* don't look at user memory in panic mode */
+ trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
+
+ kdb_printf("Dumping ftrace buffer:\n");
+
+ /* reset all but tr, trace, and overruns */
+ memset(&iter.seq, 0,
+ sizeof(struct trace_iterator) -
+ offsetof(struct trace_iterator, seq));
+ iter.iter_flags |= TRACE_FILE_LAT_FMT;
+ iter.pos = -1;
+
+ for_each_tracing_cpu(cpu)
+ iter.buffer_iter[cpu] =
+ ring_buffer_read_start(iter.tr->buffer, cpu);
+
+ if (!trace_empty(&iter))
+ trace_find_next_entry_inc(&iter);
+ while (!trace_empty(&iter)) {
+ if (!cnt)
+ kdb_printf("---------------------------------\n");
+ cnt++;
+
+ if (trace_find_next_entry_inc(&iter) != NULL && !skip_lines)
+ print_trace_line(&iter);
+ if (!skip_lines)
+ trace_printk_seq(&iter.seq);
+ else
+ skip_lines--;
+ if (KDB_FLAG(CMD_INTERRUPT))
+ goto out;
+ }
+
+ if (!cnt)
+ kdb_printf(" (ftrace buffer empty)\n");
+ else
+ kdb_printf("---------------------------------\n");
+
+out:
+ trace_flags = old_userobj;
+
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&iter.tr->data[cpu]->disabled);
+ }
+
+ for_each_tracing_cpu(cpu)
+ if (iter.buffer_iter[cpu])
+ ring_buffer_read_finish(iter.buffer_iter[cpu]);
+}
+
+/*
+ * kdb_ftdump - Dump the ftrace log buffer
+ */
+static int kdb_ftdump(int argc, const char **argv)
+{
+ int skip_lines = 0;
+ char *cp;
+
+ if (argc > 1)
+ return KDB_ARGCOUNT;
+
+ if (argc) {
+ skip_lines = simple_strtol(argv[1], &cp, 0);
+ if (*cp)
+ skip_lines = 0;
+ }
+
+ kdb_trap_printk++;
+ ftrace_dump_buf(skip_lines);
+ kdb_trap_printk--;
+
+ return 0;
+}
+
+static __init int kdb_ftrace_register(void)
+{
+ kdb_register_repeat("ftdump", kdb_ftdump, "", "Dump ftrace log",
+ 0, KDB_REPEAT_NONE);
+ return 0;
+}
+
+late_initcall(kdb_ftrace_register);
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 39/40] debug_core: Turn off tracing while in the debugger
2010-01-15 0:10 ` Steven Rostedt
@ 2010-01-15 14:03 ` Jason Wessel
2010-01-15 15:04 ` Steven Rostedt
0 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-15 14:03 UTC (permalink / raw)
To: rostedt; +Cc: linux-kernel, kgdb-bugreport, mingo
Steven Rostedt wrote:
> On Thu, 2010-01-14 at 08:59 -0600, Jason Wessel wrote:
>
>> The kernel debugger should turn off kernel tracing any time the
>> debugger is active and restore it on resume.
>>
>> CC: Steven Rostedt <rostedt@goodmis.org>
>> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
>> ---
>> kernel/debug/debug_core.c | 8 ++++++++
>> 1 files changed, 8 insertions(+), 0 deletions(-)
>>
>> diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
>> index 6ca3f7c..464aa65 100644
>> --- a/kernel/debug/debug_core.c
>> +++ b/kernel/debug/debug_core.c
>> @@ -474,6 +474,7 @@ static int kgdb_cpu_enter(struct kgdb_state *ks, struct pt_regs *regs)
>> int sstep_tries = 100;
>> int error;
>> int i, cpu;
>> + int trace_on = 0;
>> acquirelock:
>> /*
>> * Interrupts will be restored by the 'trap return' code, except when
>> @@ -518,6 +519,8 @@ return_normal:
>> */
>> if (arch_kgdb_ops.correct_hw_break)
>> arch_kgdb_ops.correct_hw_break();
>> + if (trace_on)
>> + tracing_on();
>> atomic_set(&cpu_in_kgdb[cpu], 0);
>> touch_softlockup_watchdog_sync();
>> clocksource_touch_watchdog();
>> @@ -592,6 +595,9 @@ return_normal:
>> kgdb_single_step = 0;
>> kgdb_contthread = current;
>> exception_level = 0;
>> + trace_on = tracing_is_on();
>> + if (trace_on)
>> + tracing_off();
>>
>
> Hmm, what happens if tracing gets turned on by something else? Will it
> break this code? If so, we may need to do something different here.
>
What else do you imagine would turn on tracing, or what might break?
At the point in time that this is called all the slave CPUs are rounded
up, and a single CPU remains executing as the "master" cpu inside the
debug core. There are two exit points from this context depending on
the state of how you are resuming system, where we turn tracing back on,
if it was on prior to entry to the kernel debug context.
I debated about using an atomic_inc and also allowing the slave_cpu
entry to turn it off, because that actually happens first, and you can
actually see that in the function tracer log up to the point that the
master turns off tracing.
The approach employed by this patch seemed the most simplistic, and
definitely stopped the trace log, while the debugger was active. This
particular problem with having tracing active while in the kernel debug
context was not even discovered until kdb ftdump was implemented. We
don't really want to do much of anything except keep minimal HW alive
while in the kernel debugger context. I am open to suggestions if you
think we need something more here. I can also hard code a test if you
believe there is a condition that requires some investigation.
Thanks,
Jason.
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 39/40] debug_core: Turn off tracing while in the debugger
2010-01-15 14:03 ` Jason Wessel
@ 2010-01-15 15:04 ` Steven Rostedt
0 siblings, 0 replies; 56+ messages in thread
From: Steven Rostedt @ 2010-01-15 15:04 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo
On Fri, 2010-01-15 at 08:03 -0600, Jason Wessel wrote:
> What else do you imagine would turn on tracing, or what might break?
>
> At the point in time that this is called all the slave CPUs are rounded
> up, and a single CPU remains executing as the "master" cpu inside the
> debug core. There are two exit points from this context depending on
> the state of how you are resuming system, where we turn tracing back on,
> if it was on prior to entry to the kernel debug context.
>
> I debated about using an atomic_inc and also allowing the slave_cpu
> entry to turn it off, because that actually happens first, and you can
> actually see that in the function tracer log up to the point that the
> master turns off tracing.
>
> The approach employed by this patch seemed the most simplistic, and
> definitely stopped the trace log, while the debugger was active. This
> particular problem with having tracing active while in the kernel debug
> context was not even discovered until kdb ftdump was implemented. We
> don't really want to do much of anything except keep minimal HW alive
> while in the kernel debugger context. I am open to suggestions if you
> think we need something more here. I can also hard code a test if you
> believe there is a condition that requires some investigation.
Ah, if this is done by stopping the box, then it should be pretty safe.
There's two other ways that tracing can be enabled.
One, if someone modifies the kernel and adds "tracing_on()" somewhere.
Which, if happens, is the users fault. You change the kernel, you are
responsible for the consequences.
The other, which can happen from user land, is the "function:traceon"
feature.
# echo 'schedule:traceon' > /sys/kernel/debug/tracing/set_ftrace_filter
This will not add schedule to the ftrace filter, but instead it will
attach a check to schedule that will make the tracer enabled.
If someone attaches a "traceon" command to a function that might be
called by the kernel debugger, then you may have an issue. But this too,
may just be blamed on the user.
-- Steve
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-14 20:46 ` Russell King - ARM Linux
@ 2010-01-18 14:30 ` Jason Wessel
2010-01-20 16:03 ` Russell King - ARM Linux
0 siblings, 1 reply; 56+ messages in thread
From: Jason Wessel @ 2010-01-18 14:30 UTC (permalink / raw)
To: Russell King - ARM Linux
Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
Russell King - ARM Linux wrote:
> On Thu, Jan 14, 2010 at 02:29:54PM -0600, Jason Wessel wrote:
>
>> Russell King - ARM Linux wrote:
>>
>>> I have a similar patch which implements the hook properly - but
>>> with one caveat. It needs a review to ensure that its safe to return
>>> from die(). Until that's established, this patch can not be merged.
>>>
>> I completed the analysis on your patch and yes, it is safe to return
>> from __die() and die() the way you currently structured it, but it
>> doesn't work quite the same as on some other architectures.
>>
>> After changing kgdb.c to register with the die notifier, I stepped
>> through your code with an ICE, as well as running my regression tests
>> which panic, oops, bad access etc...
>>
>> While kernel execution does happen to continue to work, I don't know
>> that you really want to continue execution.
>>
>> 1) The kernel is marked tainted
>> 2) bust_spinlocks() was toggled for a while
>>
>> On x86 for example, the notifier is invoked prior to the
>> bust_spinlocks() etc... and then it can pass the exception along to
>> the rest of the system (which can result in something bad, but
>> remember the human behind the kernel debugger controls did it for some
>> reason or another).
>>
>
> On x86, it's called in multiple places - both before die(), and also
> inside __die().
>
> In __die(), notify_die() gets called with DIE_OOPS. There's also a
> pile of notify_die() calls in arch/x86/kernel/traps.c, which we don't
> implement on ARM yet - it's unclear what's required here, and until
> we have a user of notify_die()...
>
>
Initially I was just looking to get the memory violation tests to pass
on ARM, where the kernel debugger can catch an invalid memory write for
instance. That means anything that generates any kind of system fault
should jump into the debugger via the die notifier. There might be
other places for this on ARM, but I figured we could start with the
passing the memory fault tests first.
>> I made the following addition to your patch, and then it behaved as
>> the other archs do with respect to passing along the result of the
>> exception. Given this information, would you be willing to merge your
>> patch and possibly fold in the change below, or further comment?
>>
>
> This changes the behaviour away from x86, so I'm not sure it's the
> right thing to do. For instance, it means that kexec won't get to
> know about the oops on ARM if NOTIFY_STOP is returned, whereas on
> x86 it will.
>
> Maybe this hook wasn't meant for kgdb - what does kgdb use on x86?
>
On x86, kgdb uses the notify die hook. It is possible that there are
some inconsistent uses of the notifiy_die(), but the general idea is
that any user in the hook path can elect to consume the exception and
allow the system to restore.
In terms of kgdb's use of this, I have only found it useful for
programmatic testing of exception cases. Specifically when using kdb,
the default are always to propagate exceptions unless it was a
breakpoint or single step exception which was set by the kernel debugger.
That being said, you patch works for the purpose of catching the
exception and returning with or without the addition of an earlier
return before bust_spinlocks() which I had proposed.
Jason.
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-18 14:30 ` Jason Wessel
@ 2010-01-20 16:03 ` Russell King - ARM Linux
2010-01-20 17:01 ` Jason Wessel
0 siblings, 1 reply; 56+ messages in thread
From: Russell King - ARM Linux @ 2010-01-20 16:03 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
On Mon, Jan 18, 2010 at 08:30:04AM -0600, Jason Wessel wrote:
> That being said, you patch works for the purpose of catching the
> exception and returning with or without the addition of an earlier
> return before bust_spinlocks() which I had proposed.
So does that mean I can have an acked-by for the patch?
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger
2010-01-20 16:03 ` Russell King - ARM Linux
@ 2010-01-20 17:01 ` Jason Wessel
0 siblings, 0 replies; 56+ messages in thread
From: Jason Wessel @ 2010-01-20 17:01 UTC (permalink / raw)
To: Russell King - ARM Linux
Cc: linux-kernel, kgdb-bugreport, mingo, linux-arm-kernel
Russell King - ARM Linux wrote:
> On Mon, Jan 18, 2010 at 08:30:04AM -0600, Jason Wessel wrote:
>
>> That being said, you patch works for the purpose of catching the
>> exception and returning with or without the addition of an earlier
>> return before bust_spinlocks() which I had proposed.
>>
>
> So does that mean I can have an acked-by for the patch?
>
Absolutely.
Jason.
Acked-by: Jason Wessel <jason.wessel@windriver.com>
^ permalink raw reply [flat|nested] 56+ messages in thread
* Re: [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
` (39 preceding siblings ...)
2010-01-14 14:59 ` [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer Jason Wessel
@ 2010-01-30 2:02 ` Jon Masters
40 siblings, 0 replies; 56+ messages in thread
From: Jon Masters @ 2010-01-30 2:02 UTC (permalink / raw)
To: Jason Wessel; +Cc: linux-kernel, kgdb-bugreport, mingo
On Thu, 2010-01-14 at 08:58 -0600, Jason Wessel wrote:
> This is version 2 of the series posted in December.
>
> Thank you very much to everyone who provided feedback on the original
> patch set.
Did I mention, you're *awesome*. Thanks so much for this patch series,
it's really helpful and works just dandy. It's far easier to figure out
the netfilter crash I've been seeing if I can actually poke properly.
Jon.
^ permalink raw reply [flat|nested] 56+ messages in thread
end of thread, other threads:[~2010-01-30 2:02 UTC | newest]
Thread overview: 56+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-01-14 14:58 [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jason Wessel
2010-01-14 14:58 ` [PATCH 01/40] softlockup: add sched_clock_tick() to avoid kernel warning on kgdb resume Jason Wessel
2010-01-14 14:58 ` [PATCH 02/40] x86,hw_breakpoint,kgdb: kgdb to use hw_breakpoint API Jason Wessel
2010-01-14 14:58 ` [PATCH 03/40] Move kernel/kgdb.c to kernel/debug/debug_core.c Jason Wessel
2010-01-14 14:59 ` [PATCH 04/40] Separate the gdbstub from the debug core Jason Wessel
2010-01-14 14:59 ` [PATCH 05/40] kgdb: eliminate kgdb_wait(), all cpus enter the same way Jason Wessel
2010-01-14 14:59 ` [PATCH 06/40] kgdb,sparc: Add in kgdb_arch_set_pc for sparc Jason Wessel
2010-01-14 14:59 ` [PATCH 07/40] kgdb,sh: update superh kgdb exception handling Jason Wessel
2010-01-14 14:59 ` [PATCH 08/40] kgdb,blackfin: Add in kgdb_arch_set_pc for blackfin Jason Wessel
2010-01-14 14:59 ` [PATCH 09/40] kdb: core for kgdb back end (1 of 2) Jason Wessel
2010-01-14 14:59 ` [PATCH 10/40] kdb: core for kgdb back end (2 " Jason Wessel
2010-01-14 14:59 ` [PATCH 11/40] kgdb: core changes to support kdb Jason Wessel
2010-01-14 14:59 ` [PATCH 12/40] kgdb,8250,pl011: Return immediately from console poll Jason Wessel
2010-01-14 14:59 ` [PATCH 13/40] sh,sh-sci: Use NO_POLL_CHAR in the SCIF polled console code Jason Wessel
2010-01-14 14:59 ` [PATCH 14/40] sparc,sunzilog: Add console polling support for sunzilog serial driver Jason Wessel
2010-01-14 14:59 ` [PATCH 15/40] kgdb: gdb "monitor" -> kdb passthrough Jason Wessel
2010-01-14 14:59 ` [PATCH 16/40] kgdboc,keyboard: Keyboard driver for kdb with kgdb Jason Wessel
2010-01-14 14:59 ` [PATCH 17/40] kgdb,docs: Update the kgdb docs to include kdb Jason Wessel
2010-01-14 14:59 ` [PATCH 18/40] kgdb: remove post_primary_code references Jason Wessel
2010-01-14 14:59 ` [PATCH 19/40] x86,kgdb: Add low level debug hook Jason Wessel
2010-01-14 14:59 ` [PATCH 20/40] arm,kgdb: Add hook to catch an oops with debugger Jason Wessel
2010-01-14 17:48 ` Russell King - ARM Linux
2010-01-14 18:57 ` Jason Wessel
2010-01-14 20:29 ` Jason Wessel
2010-01-14 20:46 ` Russell King - ARM Linux
2010-01-18 14:30 ` Jason Wessel
2010-01-20 16:03 ` Russell King - ARM Linux
2010-01-20 17:01 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 21/40] powerpc,kgdb: Introduce low level trap catching Jason Wessel
2010-01-14 14:59 ` [PATCH 22/40] mips,kgdb: kdb low level trap catch and stack trace Jason Wessel
2010-01-14 17:29 ` David Daney
2010-01-14 22:32 ` Jason Wessel
2010-01-14 14:59 ` [PATCH 23/40] kgdb: Add the ability to schedule a breakpoint via a tasklet Jason Wessel
2010-01-14 14:59 ` [PATCH 24/40] kgdboc,kdb: Allow kdb to work on a non open console port Jason Wessel
2010-01-14 14:59 ` [PATCH 25/40] printk,kdb: capture printk() when in kdb shell Jason Wessel
2010-01-14 14:59 ` [PATCH 26/40] keyboard, input: Add hook to input to allow low level event clear Jason Wessel
2010-01-14 14:59 ` [PATCH 27/40] debug_core,kdb: Allow the debug core to process a recursive debug entry Jason Wessel
2010-01-14 14:59 ` [PATCH 28/40] kdb,panic,debug_core: Allow the debug core to receive a panic before smp_send_stop() Jason Wessel
2010-01-14 14:59 ` [PATCH 29/40] MAINTAINERS: update kgdb, kdb, and debug_core info Jason Wessel
2010-01-14 14:59 ` [PATCH 30/40] kgdboc,debug_core: Add call backs to allow kernel mode switching Jason Wessel
2010-01-14 14:59 ` [PATCH 31/40] kgdb: add ops arg to kgdb console active & restore hooks Jason Wessel
2010-01-14 14:59 ` [PATCH 32/40] drm: add KGDB/KDB support Add support for KDB entry/exit Jason Wessel
2010-01-14 14:59 ` [PATCH 33/40] kms,kdb: Force unblank a console device Jason Wessel
2010-01-14 14:59 ` [PATCH 34/40] i915: when kgdb is active display compression should be off Jason Wessel
2010-01-14 14:59 ` [PATCH 35/40] drm_fb_helper: Preserve capability to use atomic kms Jason Wessel
2010-01-14 14:59 ` [PATCH 36/40] drm,i915 - atomic mutex hacks Jason Wessel
2010-01-14 14:59 ` [PATCH 37/40] kgdb,docs: Update the kgdb docs to include kms Jason Wessel
2010-01-14 14:59 ` [PATCH 38/40] kgdbts,sh: Add in breakpoint pc offset for superh Jason Wessel
2010-01-14 14:59 ` [PATCH 39/40] debug_core: Turn off tracing while in the debugger Jason Wessel
2010-01-15 0:10 ` Steven Rostedt
2010-01-15 14:03 ` Jason Wessel
2010-01-15 15:04 ` Steven Rostedt
2010-01-14 14:59 ` [PATCH 40/40] ftrace,kdb: Extend kdb to be able to dump the ftrace buffer Jason Wessel
2010-01-15 0:14 ` Steven Rostedt
2010-01-15 13:15 ` Jason Wessel
2010-01-30 2:02 ` [PATCH 0/40] kgdb, kdb and atomic kernel modesetting series Jon Masters
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