From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Oleg Nesterov <oleg@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [GIT PULL] perf fixes
Date: Tue, 23 Oct 2012 13:02:07 +0200 [thread overview]
Message-ID: <20121023110207.GA28324@gmail.com> (raw)
Linus,
Please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus
HEAD: ef8ff74ed8dd9d4b3ba8cb9f2fc927a27c697a8b Merge branch 'tip/perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace into perf/urgent
Most of these are uprobes race fixes from Oleg, and their
preparatory cleanups. (It's larger than what I'd normally send
for an -rc kernel, but they looked significant enough to not
delay them.)
There's also an oprofile fix and an uncore PMU fix.
Thanks,
Ingo
------------------>
Dan Carpenter (1):
oprofile, x86: Fix wrapping bug in op_x86_get_ctrl()
Oleg Nesterov (19):
uprobes: Do not leak UTASK_BP_HIT if find_active_uprobe() fails
uprobes: Do not setup ->active_uprobe/state prematurely
uprobes: Fix UPROBE_SKIP_SSTEP checks in handle_swbp()
uprobes: Kill UTASK_BP_HIT state
uprobes: Move clear_thread_flag(TIF_UPROBE) to uprobe_notify_resume()
uprobes: Change write_opcode() to use FOLL_FORCE
uprobes: Change valid_vma() to demand VM_MAYEXEC rather than VM_EXEC
uprobes: Restrict valid_vma(false) to skip VM_SHARED vmas
uprobes: Kill set_swbp()->is_swbp_at_addr()
uprobes: Introduce copy_opcode(), kill read_opcode()
uprobes: Kill set_orig_insn()->is_swbp_at_addr()
uprobes: Simplify is_swbp_at_addr(), remove stale comments
uprobes/x86: Only rep+nop can be emulated correctly
uprobes: Don't return success if alloc_uprobe() fails
uprobes: Do not delete uprobe if uprobe_unregister() fails
uprobes: Fix handle_swbp() vs unregister() + register() race
uprobes: Introduce prepare_uprobe()
uprobes: Fix prepare_uprobe() race with itself
uprobes: Fix the racy uprobe->flags manipulation
Vaibhav Nagarnaik (1):
ring-buffer: Check for uninitialized cpu buffer before resizing
Yan, Zheng (1):
perf/x86: Disable uncore on virtualized CPUs
arch/x86/kernel/cpu/perf_event_intel_uncore.c | 3 +
arch/x86/kernel/signal.c | 4 +-
arch/x86/kernel/uprobes.c | 16 +-
arch/x86/oprofile/nmi_int.c | 2 +-
include/linux/uprobes.h | 11 -
kernel/events/uprobes.c | 345 ++++++++++++--------------
kernel/trace/ring_buffer.c | 4 +
7 files changed, 173 insertions(+), 212 deletions(-)
diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
index 99d96a4..5df8d32 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
@@ -2926,6 +2926,9 @@ static int __init intel_uncore_init(void)
if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
return -ENODEV;
+ if (cpu_has_hypervisor)
+ return -ENODEV;
+
ret = uncore_pci_init();
if (ret)
goto fail;
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 29ad351..70b27ee 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -824,10 +824,8 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
mce_notify_process();
#endif /* CONFIG_X86_64 && CONFIG_X86_MCE */
- if (thread_info_flags & _TIF_UPROBE) {
- clear_thread_flag(TIF_UPROBE);
+ if (thread_info_flags & _TIF_UPROBE)
uprobe_notify_resume(regs);
- }
/* deal with pending signal delivery */
if (thread_info_flags & _TIF_SIGPENDING)
diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c
index 9538f00..aafa555 100644
--- a/arch/x86/kernel/uprobes.c
+++ b/arch/x86/kernel/uprobes.c
@@ -651,31 +651,19 @@ void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
/*
* Skip these instructions as per the currently known x86 ISA.
- * 0x66* { 0x90 | 0x0f 0x1f | 0x0f 0x19 | 0x87 0xc0 }
+ * rep=0x66*; nop=0x90
*/
static bool __skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
{
int i;
for (i = 0; i < MAX_UINSN_BYTES; i++) {
- if ((auprobe->insn[i] == 0x66))
+ if (auprobe->insn[i] == 0x66)
continue;
if (auprobe->insn[i] == 0x90)
return true;
- if (i == (MAX_UINSN_BYTES - 1))
- break;
-
- if ((auprobe->insn[i] == 0x0f) && (auprobe->insn[i+1] == 0x1f))
- return true;
-
- if ((auprobe->insn[i] == 0x0f) && (auprobe->insn[i+1] == 0x19))
- return true;
-
- if ((auprobe->insn[i] == 0x87) && (auprobe->insn[i+1] == 0xc0))
- return true;
-
break;
}
return false;
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c
index 26b8a85..48768df 100644
--- a/arch/x86/oprofile/nmi_int.c
+++ b/arch/x86/oprofile/nmi_int.c
@@ -55,7 +55,7 @@ u64 op_x86_get_ctrl(struct op_x86_model_spec const *model,
val |= counter_config->extra;
event &= model->event_mask ? model->event_mask : 0xFF;
val |= event & 0xFF;
- val |= (event & 0x0F00) << 24;
+ val |= (u64)(event & 0x0F00) << 24;
return val;
}
diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index e6f0331..2459457 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -35,16 +35,6 @@ struct inode;
# include <asm/uprobes.h>
#endif
-/* flags that denote/change uprobes behaviour */
-
-/* Have a copy of original instruction */
-#define UPROBE_COPY_INSN 0x1
-
-/* Dont run handlers when first register/ last unregister in progress*/
-#define UPROBE_RUN_HANDLER 0x2
-/* Can skip singlestep */
-#define UPROBE_SKIP_SSTEP 0x4
-
struct uprobe_consumer {
int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
/*
@@ -59,7 +49,6 @@ struct uprobe_consumer {
#ifdef CONFIG_UPROBES
enum uprobe_task_state {
UTASK_RUNNING,
- UTASK_BP_HIT,
UTASK_SSTEP,
UTASK_SSTEP_ACK,
UTASK_SSTEP_TRAPPED,
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 98256bc..5cc4e7e 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -78,15 +78,23 @@ static struct mutex uprobes_mmap_mutex[UPROBES_HASH_SZ];
*/
static atomic_t uprobe_events = ATOMIC_INIT(0);
+/* Have a copy of original instruction */
+#define UPROBE_COPY_INSN 0
+/* Dont run handlers when first register/ last unregister in progress*/
+#define UPROBE_RUN_HANDLER 1
+/* Can skip singlestep */
+#define UPROBE_SKIP_SSTEP 2
+
struct uprobe {
struct rb_node rb_node; /* node in the rb tree */
atomic_t ref;
struct rw_semaphore consumer_rwsem;
+ struct mutex copy_mutex; /* TODO: kill me and UPROBE_COPY_INSN */
struct list_head pending_list;
struct uprobe_consumer *consumers;
struct inode *inode; /* Also hold a ref to inode */
loff_t offset;
- int flags;
+ unsigned long flags;
struct arch_uprobe arch;
};
@@ -100,17 +108,12 @@ struct uprobe {
*/
static bool valid_vma(struct vm_area_struct *vma, bool is_register)
{
- if (!vma->vm_file)
- return false;
-
- if (!is_register)
- return true;
+ vm_flags_t flags = VM_HUGETLB | VM_MAYEXEC | VM_SHARED;
- if ((vma->vm_flags & (VM_HUGETLB|VM_READ|VM_WRITE|VM_EXEC|VM_SHARED))
- == (VM_READ|VM_EXEC))
- return true;
+ if (is_register)
+ flags |= VM_WRITE;
- return false;
+ return vma->vm_file && (vma->vm_flags & flags) == VM_MAYEXEC;
}
static unsigned long offset_to_vaddr(struct vm_area_struct *vma, loff_t offset)
@@ -193,19 +196,44 @@ bool __weak is_swbp_insn(uprobe_opcode_t *insn)
return *insn == UPROBE_SWBP_INSN;
}
+static void copy_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *opcode)
+{
+ void *kaddr = kmap_atomic(page);
+ memcpy(opcode, kaddr + (vaddr & ~PAGE_MASK), UPROBE_SWBP_INSN_SIZE);
+ kunmap_atomic(kaddr);
+}
+
+static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode)
+{
+ uprobe_opcode_t old_opcode;
+ bool is_swbp;
+
+ copy_opcode(page, vaddr, &old_opcode);
+ is_swbp = is_swbp_insn(&old_opcode);
+
+ if (is_swbp_insn(new_opcode)) {
+ if (is_swbp) /* register: already installed? */
+ return 0;
+ } else {
+ if (!is_swbp) /* unregister: was it changed by us? */
+ return 0;
+ }
+
+ return 1;
+}
+
/*
* NOTE:
* Expect the breakpoint instruction to be the smallest size instruction for
* the architecture. If an arch has variable length instruction and the
* breakpoint instruction is not of the smallest length instruction
- * supported by that architecture then we need to modify read_opcode /
+ * supported by that architecture then we need to modify is_swbp_at_addr and
* write_opcode accordingly. This would never be a problem for archs that
* have fixed length instructions.
*/
/*
* write_opcode - write the opcode at a given virtual address.
- * @auprobe: arch breakpointing information.
* @mm: the probed process address space.
* @vaddr: the virtual address to store the opcode.
* @opcode: opcode to be written at @vaddr.
@@ -216,8 +244,8 @@ bool __weak is_swbp_insn(uprobe_opcode_t *insn)
* For mm @mm, write the opcode at @vaddr.
* Return 0 (success) or a negative errno.
*/
-static int write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
- unsigned long vaddr, uprobe_opcode_t opcode)
+static int write_opcode(struct mm_struct *mm, unsigned long vaddr,
+ uprobe_opcode_t opcode)
{
struct page *old_page, *new_page;
void *vaddr_old, *vaddr_new;
@@ -226,10 +254,14 @@ static int write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
retry:
/* Read the page with vaddr into memory */
- ret = get_user_pages(NULL, mm, vaddr, 1, 0, 0, &old_page, &vma);
+ ret = get_user_pages(NULL, mm, vaddr, 1, 0, 1, &old_page, &vma);
if (ret <= 0)
return ret;
+ ret = verify_opcode(old_page, vaddr, &opcode);
+ if (ret <= 0)
+ goto put_old;
+
ret = -ENOMEM;
new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, vaddr);
if (!new_page)
@@ -264,63 +296,6 @@ put_old:
}
/**
- * read_opcode - read the opcode at a given virtual address.
- * @mm: the probed process address space.
- * @vaddr: the virtual address to read the opcode.
- * @opcode: location to store the read opcode.
- *
- * Called with mm->mmap_sem held (for read and with a reference to
- * mm.
- *
- * For mm @mm, read the opcode at @vaddr and store it in @opcode.
- * Return 0 (success) or a negative errno.
- */
-static int read_opcode(struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t *opcode)
-{
- struct page *page;
- void *vaddr_new;
- int ret;
-
- ret = get_user_pages(NULL, mm, vaddr, 1, 0, 1, &page, NULL);
- if (ret <= 0)
- return ret;
-
- vaddr_new = kmap_atomic(page);
- vaddr &= ~PAGE_MASK;
- memcpy(opcode, vaddr_new + vaddr, UPROBE_SWBP_INSN_SIZE);
- kunmap_atomic(vaddr_new);
-
- put_page(page);
-
- return 0;
-}
-
-static int is_swbp_at_addr(struct mm_struct *mm, unsigned long vaddr)
-{
- uprobe_opcode_t opcode;
- int result;
-
- if (current->mm == mm) {
- pagefault_disable();
- result = __copy_from_user_inatomic(&opcode, (void __user*)vaddr,
- sizeof(opcode));
- pagefault_enable();
-
- if (likely(result == 0))
- goto out;
- }
-
- result = read_opcode(mm, vaddr, &opcode);
- if (result)
- return result;
-out:
- if (is_swbp_insn(&opcode))
- return 1;
-
- return 0;
-}
-
-/**
* set_swbp - store breakpoint at a given address.
* @auprobe: arch specific probepoint information.
* @mm: the probed process address space.
@@ -331,18 +306,7 @@ out:
*/
int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
{
- int result;
- /*
- * See the comment near uprobes_hash().
- */
- result = is_swbp_at_addr(mm, vaddr);
- if (result == 1)
- return 0;
-
- if (result)
- return result;
-
- return write_opcode(auprobe, mm, vaddr, UPROBE_SWBP_INSN);
+ return write_opcode(mm, vaddr, UPROBE_SWBP_INSN);
}
/**
@@ -357,16 +321,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
int __weak
set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
{
- int result;
-
- result = is_swbp_at_addr(mm, vaddr);
- if (!result)
- return -EINVAL;
-
- if (result != 1)
- return result;
-
- return write_opcode(auprobe, mm, vaddr, *(uprobe_opcode_t *)auprobe->insn);
+ return write_opcode(mm, vaddr, *(uprobe_opcode_t *)auprobe->insn);
}
static int match_uprobe(struct uprobe *l, struct uprobe *r)
@@ -473,7 +428,7 @@ static struct uprobe *insert_uprobe(struct uprobe *uprobe)
spin_unlock(&uprobes_treelock);
/* For now assume that the instruction need not be single-stepped */
- uprobe->flags |= UPROBE_SKIP_SSTEP;
+ __set_bit(UPROBE_SKIP_SSTEP, &uprobe->flags);
return u;
}
@@ -495,6 +450,7 @@ static struct uprobe *alloc_uprobe(struct inode *inode, loff_t offset)
uprobe->inode = igrab(inode);
uprobe->offset = offset;
init_rwsem(&uprobe->consumer_rwsem);
+ mutex_init(&uprobe->copy_mutex);
/* add to uprobes_tree, sorted on inode:offset */
cur_uprobe = insert_uprobe(uprobe);
@@ -515,7 +471,7 @@ static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs)
{
struct uprobe_consumer *uc;
- if (!(uprobe->flags & UPROBE_RUN_HANDLER))
+ if (!test_bit(UPROBE_RUN_HANDLER, &uprobe->flags))
return;
down_read(&uprobe->consumer_rwsem);
@@ -621,29 +577,43 @@ static int copy_insn(struct uprobe *uprobe, struct file *filp)
return __copy_insn(mapping, filp, uprobe->arch.insn, bytes, uprobe->offset);
}
-/*
- * How mm->uprobes_state.count gets updated
- * uprobe_mmap() increments the count if
- * - it successfully adds a breakpoint.
- * - it cannot add a breakpoint, but sees that there is a underlying
- * breakpoint (via a is_swbp_at_addr()).
- *
- * uprobe_munmap() decrements the count if
- * - it sees a underlying breakpoint, (via is_swbp_at_addr)
- * (Subsequent uprobe_unregister wouldnt find the breakpoint
- * unless a uprobe_mmap kicks in, since the old vma would be
- * dropped just after uprobe_munmap.)
- *
- * uprobe_register increments the count if:
- * - it successfully adds a breakpoint.
- *
- * uprobe_unregister decrements the count if:
- * - it sees a underlying breakpoint and removes successfully.
- * (via is_swbp_at_addr)
- * (Subsequent uprobe_munmap wouldnt find the breakpoint
- * since there is no underlying breakpoint after the
- * breakpoint removal.)
- */
+static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
+ struct mm_struct *mm, unsigned long vaddr)
+{
+ int ret = 0;
+
+ if (test_bit(UPROBE_COPY_INSN, &uprobe->flags))
+ return ret;
+
+ mutex_lock(&uprobe->copy_mutex);
+ if (test_bit(UPROBE_COPY_INSN, &uprobe->flags))
+ goto out;
+
+ ret = copy_insn(uprobe, file);
+ if (ret)
+ goto out;
+
+ ret = -ENOTSUPP;
+ if (is_swbp_insn((uprobe_opcode_t *)uprobe->arch.insn))
+ goto out;
+
+ ret = arch_uprobe_analyze_insn(&uprobe->arch, mm, vaddr);
+ if (ret)
+ goto out;
+
+ /* write_opcode() assumes we don't cross page boundary */
+ BUG_ON((uprobe->offset & ~PAGE_MASK) +
+ UPROBE_SWBP_INSN_SIZE > PAGE_SIZE);
+
+ smp_wmb(); /* pairs with rmb() in find_active_uprobe() */
+ set_bit(UPROBE_COPY_INSN, &uprobe->flags);
+
+ out:
+ mutex_unlock(&uprobe->copy_mutex);
+
+ return ret;
+}
+
static int
install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long vaddr)
@@ -661,24 +631,9 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
if (!uprobe->consumers)
return 0;
- if (!(uprobe->flags & UPROBE_COPY_INSN)) {
- ret = copy_insn(uprobe, vma->vm_file);
- if (ret)
- return ret;
-
- if (is_swbp_insn((uprobe_opcode_t *)uprobe->arch.insn))
- return -ENOTSUPP;
-
- ret = arch_uprobe_analyze_insn(&uprobe->arch, mm, vaddr);
- if (ret)
- return ret;
-
- /* write_opcode() assumes we don't cross page boundary */
- BUG_ON((uprobe->offset & ~PAGE_MASK) +
- UPROBE_SWBP_INSN_SIZE > PAGE_SIZE);
-
- uprobe->flags |= UPROBE_COPY_INSN;
- }
+ ret = prepare_uprobe(uprobe, vma->vm_file, mm, vaddr);
+ if (ret)
+ return ret;
/*
* set MMF_HAS_UPROBES in advance for uprobe_pre_sstep_notifier(),
@@ -697,15 +652,15 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
return ret;
}
-static void
+static int
remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
{
/* can happen if uprobe_register() fails */
if (!test_bit(MMF_HAS_UPROBES, &mm->flags))
- return;
+ return 0;
set_bit(MMF_RECALC_UPROBES, &mm->flags);
- set_orig_insn(&uprobe->arch, mm, vaddr);
+ return set_orig_insn(&uprobe->arch, mm, vaddr);
}
/*
@@ -820,7 +775,7 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
struct mm_struct *mm = info->mm;
struct vm_area_struct *vma;
- if (err)
+ if (err && is_register)
goto free;
down_write(&mm->mmap_sem);
@@ -836,7 +791,7 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
if (is_register)
err = install_breakpoint(uprobe, mm, vma, info->vaddr);
else
- remove_breakpoint(uprobe, mm, info->vaddr);
+ err |= remove_breakpoint(uprobe, mm, info->vaddr);
unlock:
up_write(&mm->mmap_sem);
@@ -893,13 +848,15 @@ int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *
mutex_lock(uprobes_hash(inode));
uprobe = alloc_uprobe(inode, offset);
- if (uprobe && !consumer_add(uprobe, uc)) {
+ if (!uprobe) {
+ ret = -ENOMEM;
+ } else if (!consumer_add(uprobe, uc)) {
ret = __uprobe_register(uprobe);
if (ret) {
uprobe->consumers = NULL;
__uprobe_unregister(uprobe);
} else {
- uprobe->flags |= UPROBE_RUN_HANDLER;
+ set_bit(UPROBE_RUN_HANDLER, &uprobe->flags);
}
}
@@ -932,7 +889,7 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume
if (consumer_del(uprobe, uc)) {
if (!uprobe->consumers) {
__uprobe_unregister(uprobe);
- uprobe->flags &= ~UPROBE_RUN_HANDLER;
+ clear_bit(UPROBE_RUN_HANDLER, &uprobe->flags);
}
}
@@ -1393,10 +1350,11 @@ bool uprobe_deny_signal(void)
*/
static bool can_skip_sstep(struct uprobe *uprobe, struct pt_regs *regs)
{
- if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
- return true;
-
- uprobe->flags &= ~UPROBE_SKIP_SSTEP;
+ if (test_bit(UPROBE_SKIP_SSTEP, &uprobe->flags)) {
+ if (arch_uprobe_skip_sstep(&uprobe->arch, regs))
+ return true;
+ clear_bit(UPROBE_SKIP_SSTEP, &uprobe->flags);
+ }
return false;
}
@@ -1419,6 +1377,30 @@ static void mmf_recalc_uprobes(struct mm_struct *mm)
clear_bit(MMF_HAS_UPROBES, &mm->flags);
}
+static int is_swbp_at_addr(struct mm_struct *mm, unsigned long vaddr)
+{
+ struct page *page;
+ uprobe_opcode_t opcode;
+ int result;
+
+ pagefault_disable();
+ result = __copy_from_user_inatomic(&opcode, (void __user*)vaddr,
+ sizeof(opcode));
+ pagefault_enable();
+
+ if (likely(result == 0))
+ goto out;
+
+ result = get_user_pages(NULL, mm, vaddr, 1, 0, 1, &page, NULL);
+ if (result < 0)
+ return result;
+
+ copy_opcode(page, vaddr, &opcode);
+ put_page(page);
+ out:
+ return is_swbp_insn(&opcode);
+}
+
static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
{
struct mm_struct *mm = current->mm;
@@ -1489,38 +1471,41 @@ static void handle_swbp(struct pt_regs *regs)
}
return;
}
+ /*
+ * TODO: move copy_insn/etc into _register and remove this hack.
+ * After we hit the bp, _unregister + _register can install the
+ * new and not-yet-analyzed uprobe at the same address, restart.
+ */
+ smp_rmb(); /* pairs with wmb() in install_breakpoint() */
+ if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags)))
+ goto restart;
utask = current->utask;
if (!utask) {
utask = add_utask();
/* Cannot allocate; re-execute the instruction. */
if (!utask)
- goto cleanup_ret;
+ goto restart;
}
- utask->active_uprobe = uprobe;
+
handler_chain(uprobe, regs);
- if (uprobe->flags & UPROBE_SKIP_SSTEP && can_skip_sstep(uprobe, regs))
- goto cleanup_ret;
+ if (can_skip_sstep(uprobe, regs))
+ goto out;
- utask->state = UTASK_SSTEP;
if (!pre_ssout(uprobe, regs, bp_vaddr)) {
arch_uprobe_enable_step(&uprobe->arch);
+ utask->active_uprobe = uprobe;
+ utask->state = UTASK_SSTEP;
return;
}
-cleanup_ret:
- if (utask) {
- utask->active_uprobe = NULL;
- utask->state = UTASK_RUNNING;
- }
- if (!(uprobe->flags & UPROBE_SKIP_SSTEP))
-
- /*
- * cannot singlestep; cannot skip instruction;
- * re-execute the instruction.
- */
- instruction_pointer_set(regs, bp_vaddr);
-
+restart:
+ /*
+ * cannot singlestep; cannot skip instruction;
+ * re-execute the instruction.
+ */
+ instruction_pointer_set(regs, bp_vaddr);
+out:
put_uprobe(uprobe);
}
@@ -1552,13 +1537,12 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs)
}
/*
- * On breakpoint hit, breakpoint notifier sets the TIF_UPROBE flag. (and on
- * subsequent probe hits on the thread sets the state to UTASK_BP_HIT) and
- * allows the thread to return from interrupt.
+ * On breakpoint hit, breakpoint notifier sets the TIF_UPROBE flag and
+ * allows the thread to return from interrupt. After that handle_swbp()
+ * sets utask->active_uprobe.
*
- * On singlestep exception, singlestep notifier sets the TIF_UPROBE flag and
- * also sets the state to UTASK_SSTEP_ACK and allows the thread to return from
- * interrupt.
+ * On singlestep exception, singlestep notifier sets the TIF_UPROBE flag
+ * and allows the thread to return from interrupt.
*
* While returning to userspace, thread notices the TIF_UPROBE flag and calls
* uprobe_notify_resume().
@@ -1567,11 +1551,13 @@ void uprobe_notify_resume(struct pt_regs *regs)
{
struct uprobe_task *utask;
+ clear_thread_flag(TIF_UPROBE);
+
utask = current->utask;
- if (!utask || utask->state == UTASK_BP_HIT)
- handle_swbp(regs);
- else
+ if (utask && utask->active_uprobe)
handle_singlestep(utask, regs);
+ else
+ handle_swbp(regs);
}
/*
@@ -1580,17 +1566,10 @@ void uprobe_notify_resume(struct pt_regs *regs)
*/
int uprobe_pre_sstep_notifier(struct pt_regs *regs)
{
- struct uprobe_task *utask;
-
if (!current->mm || !test_bit(MMF_HAS_UPROBES, ¤t->mm->flags))
return 0;
- utask = current->utask;
- if (utask)
- utask->state = UTASK_BP_HIT;
-
set_thread_flag(TIF_UPROBE);
-
return 1;
}
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index b32ed0e..b979426 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1567,6 +1567,10 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
put_online_cpus();
} else {
+ /* Make sure this CPU has been intitialized */
+ if (!cpumask_test_cpu(cpu_id, buffer->cpumask))
+ goto out;
+
cpu_buffer = buffer->buffers[cpu_id];
if (nr_pages == cpu_buffer->nr_pages)
next reply other threads:[~2012-10-23 11:02 UTC|newest]
Thread overview: 376+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-23 11:02 Ingo Molnar [this message]
-- strict thread matches above, loose matches on Subject: below --
2023-01-06 11:57 [GIT PULL] perf fixes Ingo Molnar
2023-01-06 21:19 ` pr-tracker-bot
2022-10-02 10:56 Ingo Molnar
2022-10-02 16:47 ` Linus Torvalds
2022-10-03 10:55 ` Ingo Molnar
2022-10-02 17:20 ` pr-tracker-bot
2022-08-28 14:35 Ingo Molnar
2022-08-28 18:18 ` pr-tracker-bot
2022-08-06 19:10 Ingo Molnar
2022-08-07 0:50 ` pr-tracker-bot
2021-07-11 13:26 Ingo Molnar
2021-07-11 18:22 ` pr-tracker-bot
2021-06-12 12:48 Ingo Molnar
2021-06-12 19:09 ` pr-tracker-bot
2021-03-21 10:56 Ingo Molnar
2021-03-21 18:45 ` pr-tracker-bot
2020-08-15 11:21 Ingo Molnar
2020-08-16 1:55 ` pr-tracker-bot
2020-04-25 9:19 Ingo Molnar
2020-04-25 19:30 ` pr-tracker-bot
2020-03-24 9:19 Ingo Molnar
2020-03-24 17:15 ` pr-tracker-bot
2020-03-02 7:23 Ingo Molnar
2020-03-03 23:35 ` pr-tracker-bot
2020-02-15 8:53 Ingo Molnar
2020-02-15 21:25 ` pr-tracker-bot
2020-01-18 17:58 Ingo Molnar
2020-01-18 21:05 ` pr-tracker-bot
2019-12-21 16:16 Ingo Molnar
2019-12-21 18:55 ` pr-tracker-bot
2019-12-17 11:34 Ingo Molnar
2019-12-17 19:06 ` Linus Torvalds
2019-12-18 6:58 ` Ingo Molnar
2019-12-17 19:20 ` pr-tracker-bot
2019-12-01 22:15 Ingo Molnar
2019-12-02 4:40 ` pr-tracker-bot
2019-11-16 21:33 Ingo Molnar
2019-11-17 0:35 ` pr-tracker-bot
2019-11-01 17:48 Ingo Molnar
2019-11-01 18:48 ` Linus Torvalds
2019-11-01 20:30 ` Ingo Molnar
2019-11-01 21:01 ` Ingo Molnar
2019-11-01 22:15 ` Linus Torvalds
2019-11-01 19:10 ` pr-tracker-bot
2019-10-12 13:31 Ingo Molnar
2019-10-12 22:35 ` pr-tracker-bot
2019-07-14 12:01 Ingo Molnar
2019-07-14 18:45 ` pr-tracker-bot
2019-06-29 8:54 Ingo Molnar
2019-06-29 11:45 ` pr-tracker-bot
2019-06-02 17:39 Ingo Molnar
2019-06-02 18:15 ` pr-tracker-bot
2019-05-16 16:05 Ingo Molnar
2019-05-16 18:20 ` pr-tracker-bot
2019-05-05 12:47 Ingo Molnar
2019-05-05 22:10 ` pr-tracker-bot
2019-04-20 7:43 Ingo Molnar
2019-04-20 19:25 ` pr-tracker-bot
2019-04-12 13:06 Ingo Molnar
2019-04-13 4:05 ` pr-tracker-bot
2019-02-17 10:10 Ingo Molnar
2019-02-17 16:50 ` pr-tracker-bot
2019-02-10 9:01 Ingo Molnar
2019-02-10 18:30 ` pr-tracker-bot
2019-01-11 7:44 Ingo Molnar
2019-01-11 18:00 ` pr-tracker-bot
2018-11-30 6:25 Ingo Molnar
2018-11-30 21:00 ` pr-tracker-bot
2018-11-17 10:55 Ingo Molnar
2018-11-18 20:05 ` pr-tracker-bot
2018-10-20 8:10 Ingo Molnar
2018-10-20 13:28 ` Greg Kroah-Hartman
2018-10-11 9:12 Ingo Molnar
2018-10-11 12:32 ` Greg Kroah-Hartman
2018-10-11 8:59 Ingo Molnar
2018-10-05 9:42 Ingo Molnar
2018-10-05 9:55 ` Ingo Molnar
2018-10-05 23:30 ` Greg Kroah-Hartman
2018-09-15 13:11 Ingo Molnar
2018-07-30 17:53 Ingo Molnar
2018-07-13 19:59 Ingo Molnar
2018-06-30 8:44 Ingo Molnar
2018-06-04 9:04 Ingo Molnar
2018-03-31 10:40 Ingo Molnar
2018-03-25 8:53 Ingo Molnar
2018-02-06 21:29 Ingo Molnar
2017-12-06 22:17 Ingo Molnar
2017-11-26 12:40 Ingo Molnar
2017-11-05 14:40 Ingo Molnar
2017-11-09 8:13 ` Markus Trippelsdorf
2017-10-14 16:04 Ingo Molnar
2017-09-13 18:00 Ingo Molnar
2017-09-12 15:32 Ingo Molnar
2017-07-21 10:15 Ingo Molnar
2017-06-10 8:39 Ingo Molnar
2017-05-12 7:31 Ingo Molnar
2017-03-07 20:30 Ingo Molnar
2017-02-28 8:01 Ingo Molnar
2017-02-11 18:12 Ingo Molnar
2017-02-02 21:01 Ingo Molnar
2017-01-18 9:27 Ingo Molnar
2017-01-15 9:59 Ingo Molnar
2016-12-23 22:50 Ingo Molnar
2016-12-07 18:45 Ingo Molnar
2016-11-23 9:00 Ingo Molnar
2016-11-14 7:56 Ingo Molnar
2016-10-28 19:41 Ingo Molnar
2016-10-18 11:07 Ingo Molnar
2016-09-13 18:14 Ingo Molnar
2016-08-18 20:38 Ingo Molnar
2016-08-12 19:35 Ingo Molnar
2016-07-26 14:13 Ingo Molnar
2016-07-08 13:42 Ingo Molnar
2016-06-10 12:50 Ingo Molnar
2016-05-13 18:51 Ingo Molnar
2016-05-06 11:26 Ingo Molnar
2016-04-28 17:56 Ingo Molnar
2016-04-03 11:00 Ingo Molnar
2016-02-20 11:14 Ingo Molnar
2016-01-14 10:03 Ingo Molnar
2016-01-08 12:46 Ingo Molnar
2015-12-08 4:22 Ingo Molnar
2015-09-17 8:02 Ingo Molnar
2015-09-02 18:11 Ingo Molnar
2015-08-22 12:19 Ingo Molnar
2015-08-14 7:12 Ingo Molnar
2015-07-18 2:53 Ingo Molnar
2015-07-06 15:29 Ingo Molnar
2015-06-13 14:29 Ingo Molnar
2015-06-05 8:37 Ingo Molnar
2015-05-15 7:17 Ingo Molnar
2015-05-06 12:52 Ingo Molnar
2015-04-03 13:11 Ingo Molnar
2015-03-17 16:48 Ingo Molnar
2015-03-01 17:00 Ingo Molnar
2015-02-20 13:40 Ingo Molnar
2015-01-30 18:44 Ingo Molnar
2015-01-17 14:15 Ingo Molnar
2015-01-11 8:42 Ingo Molnar
2014-11-20 7:46 Ingo Molnar
2014-10-31 11:13 Ingo Molnar
2014-11-03 9:02 ` Paul Bolle
2014-11-03 10:04 ` Peter Zijlstra
2014-09-19 10:46 Ingo Molnar
2014-08-24 20:25 Ingo Molnar
2014-07-16 11:11 Ingo Molnar
2014-06-18 16:39 Ingo Molnar
2014-05-22 8:04 Ingo Molnar
2014-05-01 6:34 Ingo Molnar
2014-04-20 8:02 Ingo Molnar
2014-04-19 10:41 Ingo Molnar
2014-04-16 13:04 Ingo Molnar
2014-03-22 9:06 Ingo Molnar
2014-03-16 16:34 Ingo Molnar
2014-03-02 8:51 Ingo Molnar
2014-02-22 19:16 Ingo Molnar
2014-02-09 8:01 Ingo Molnar
2014-01-25 7:30 Ingo Molnar
2014-01-19 12:08 Ingo Molnar
2013-12-19 16:52 Ingo Molnar
2013-12-02 14:39 Ingo Molnar
2013-11-15 19:46 Ingo Molnar
2013-11-01 9:56 Ingo Molnar
2013-10-29 10:04 Ingo Molnar
2013-10-26 12:24 Ingo Molnar
2013-10-28 8:28 ` Markus Trippelsdorf
2013-10-28 9:02 ` ------------------------------ Markus Trippelsdorf
2013-10-28 9:34 ` Markus Trippelsdorf
2013-10-28 12:34 ` Arnaldo Carvalho de Melo
2013-10-28 12:42 ` Arnaldo Carvalho de Melo
2013-10-28 12:59 ` Markus Trippelsdorf
2013-10-29 9:50 ` Stephane Eranian
2013-10-29 10:06 ` Ingo Molnar
2013-10-29 12:47 ` Arnaldo Carvalho de Melo
2013-10-08 12:12 Ingo Molnar
2013-09-28 18:03 Ingo Molnar
2013-09-29 11:47 ` Markus Trippelsdorf
2013-09-29 21:33 ` Andi Kleen
2013-09-29 22:47 ` Markus Trippelsdorf
2013-09-30 6:27 ` Ingo Molnar
2013-09-30 18:54 ` Andi Kleen
2013-10-01 8:42 ` Ingo Molnar
2013-09-25 18:00 Ingo Molnar
2013-09-18 16:06 Ingo Molnar
2013-09-12 13:38 Ingo Molnar
2013-09-12 18:03 ` Linus Torvalds
2013-09-12 18:10 ` Linus Torvalds
2013-09-12 18:43 ` Arnaldo Carvalho de Melo
2013-09-12 19:12 ` Arnaldo Carvalho de Melo
2013-09-12 19:13 ` Linus Torvalds
2013-09-12 19:55 ` Ingo Molnar
2013-09-12 19:58 ` David Ahern
2013-09-12 20:02 ` Arnaldo Carvalho de Melo
2013-09-12 20:31 ` Ingo Molnar
2013-09-12 20:43 ` Ingo Molnar
2013-09-12 20:18 ` Ingo Molnar
2013-09-12 20:38 ` Arnaldo Carvalho de Melo
2013-09-12 20:46 ` Ingo Molnar
2013-09-12 21:09 ` David Ahern
2013-09-12 21:18 ` Ingo Molnar
2013-09-12 22:10 ` David Ahern
2013-09-13 5:09 ` Ingo Molnar
2013-09-13 9:32 ` Jean Pihet
2013-09-13 9:45 ` Ingo Molnar
2013-09-13 17:15 ` Jean Pihet
2013-09-12 18:51 ` Linus Torvalds
2013-09-12 20:33 ` Ingo Molnar
2013-09-12 20:38 ` Linus Torvalds
2013-09-12 20:49 ` Ingo Molnar
2013-09-12 20:52 ` Linus Torvalds
2013-09-12 21:01 ` Ingo Molnar
2013-09-12 20:10 ` Ingo Molnar
2013-08-13 16:51 Ingo Molnar
2013-07-10 8:52 Ingo Molnar
2013-06-26 8:52 Ingo Molnar
2013-06-20 8:58 Ingo Molnar
2013-05-05 10:10 Ingo Molnar
2013-04-21 8:16 Ingo Molnar
2013-04-14 15:20 Ingo Molnar
2013-03-21 9:56 Ingo Molnar
2013-03-11 14:28 Ingo Molnar
2013-02-26 7:02 Ingo Molnar
2013-03-14 20:32 ` Linus Torvalds
2013-03-14 21:06 ` Linus Torvalds
2013-03-14 22:09 ` Stephane Eranian
2013-03-14 22:17 ` Linus Torvalds
2013-03-14 22:19 ` Stephane Eranian
2013-03-14 22:42 ` Stephane Eranian
2013-03-14 22:53 ` Stephane Eranian
2013-03-14 23:11 ` Stephane Eranian
2013-03-15 0:24 ` Stephane Eranian
2013-03-15 1:06 ` Linus Torvalds
2013-03-15 8:01 ` Stephane Eranian
2013-03-15 10:50 ` Stephane Eranian
2013-02-04 18:20 Ingo Molnar
2012-12-01 11:11 Ingo Molnar
2012-10-26 14:44 Ingo Molnar
2012-10-20 0:56 Ingo Molnar
2012-09-21 19:08 Ingo Molnar
2012-09-13 14:39 Ingo Molnar
2012-08-23 10:59 Ingo Molnar
2012-08-20 9:08 Ingo Molnar
2012-08-21 7:59 ` Ingo Molnar
2012-08-05 17:43 Ingo Molnar
2012-08-03 16:40 Ingo Molnar
2012-07-14 7:51 Ingo Molnar
2012-06-22 13:36 Ingo Molnar
2012-06-22 18:07 ` Linus Torvalds
2012-06-22 18:38 ` Hagen Paul Pfeifer
2012-06-22 18:52 ` Linus Torvalds
2012-06-22 19:06 ` Hagen Paul Pfeifer
2012-06-22 19:54 ` Steven Rostedt
[not found] ` <86448d73-2e19-416f-8104-ce72aa5d76eb@email.android.com>
2012-06-22 23:18 ` Steven Rostedt
2012-06-23 0:51 ` Arjan van de Ven
2012-06-23 1:57 ` Steven Rostedt
2012-06-23 18:25 ` H. Peter Anvin
2012-06-22 18:50 ` Steven Rostedt
2012-06-15 18:48 Ingo Molnar
2012-06-08 9:20 Ingo Molnar
2012-05-30 15:39 Ingo Molnar
2012-05-17 8:19 Ingo Molnar
2012-04-27 6:32 Ingo Molnar
2012-04-16 17:48 Ingo Molnar
2012-04-14 10:54 Ingo Molnar
2012-04-03 22:40 Ingo Molnar
2012-03-13 16:56 Ingo Molnar
2012-03-05 9:27 Ingo Molnar
2012-03-02 10:47 Ingo Molnar
2012-02-10 12:45 Ingo Molnar
2012-02-02 10:00 Ingo Molnar
2012-01-26 18:11 Ingo Molnar
2011-12-29 21:02 Ingo Molnar
2011-12-09 6:16 Ingo Molnar
2011-12-05 19:13 Ingo Molnar
2011-11-07 18:49 Ingo Molnar
2011-11-07 19:00 ` Linus Torvalds
2011-11-07 19:50 ` Ingo Molnar
2011-08-22 17:00 Ingo Molnar
2011-08-11 8:17 Ingo Molnar
2011-07-07 18:11 Ingo Molnar
2011-06-19 8:44 Ingo Molnar
2011-06-13 9:53 Ingo Molnar
2011-06-08 13:46 Ingo Molnar
2011-05-28 16:34 Ingo Molnar
2011-05-24 2:41 Ingo Molnar
2011-05-23 13:41 Ingo Molnar
2011-05-23 22:10 ` Eric Dumazet
2011-05-23 22:19 ` Frederic Weisbecker
2011-05-23 22:22 ` Eric Dumazet
2011-05-20 17:18 Ingo Molnar
2011-05-17 22:07 Ingo Molnar
2011-05-07 18:20 Ingo Molnar
2011-04-29 18:17 Ingo Molnar
2011-04-22 13:42 Ingo Molnar
2011-04-19 15:56 Ingo Molnar
2011-04-16 10:03 Ingo Molnar
2011-04-07 17:48 Ingo Molnar
2011-04-02 10:25 Ingo Molnar
2011-03-25 13:11 Ingo Molnar
2011-03-10 7:53 Ingo Molnar
2011-02-28 17:34 Ingo Molnar
2011-02-22 16:03 Ingo Molnar
2011-02-15 16:58 Ingo Molnar
2011-02-06 11:27 Ingo Molnar
2011-02-03 15:47 Ingo Molnar
2011-01-24 13:34 Ingo Molnar
2011-01-24 19:48 ` Linus Torvalds
2011-01-24 20:07 ` Ingo Molnar
2011-01-24 20:11 ` Ingo Molnar
2011-01-24 20:17 ` Ingo Molnar
2011-01-24 20:17 ` Linus Torvalds
2011-01-24 20:27 ` Linus Torvalds
2011-01-24 20:38 ` Arnaldo Carvalho de Melo
2011-01-24 21:13 ` Linus Torvalds
2011-01-24 21:25 ` Ingo Molnar
2011-01-24 22:00 ` Arnaldo Carvalho de Melo
2011-01-25 0:16 ` Ingo Molnar
2011-01-24 20:37 ` Davidlohr Bueso
2011-01-24 20:14 ` Arnaldo Carvalho de Melo
2011-01-18 18:59 Ingo Molnar
2011-01-18 9:42 Ingo Molnar
2011-01-15 15:24 Ingo Molnar
2011-01-11 11:32 Ingo Molnar
2011-01-03 19:04 Ingo Molnar
2010-12-23 12:56 Ingo Molnar
2010-12-19 15:34 Ingo Molnar
2010-12-08 7:55 Ingo Molnar
2010-11-28 17:36 Ingo Molnar
2010-11-26 13:20 Ingo Molnar
2010-11-11 10:38 Ingo Molnar
2010-10-30 18:21 Ingo Molnar
2010-10-13 15:21 Ingo Molnar
2010-10-05 14:49 Ingo Molnar
2010-09-26 8:38 Ingo Molnar
2010-09-21 19:39 Ingo Molnar
2010-09-10 14:26 Ingo Molnar
2010-08-25 17:44 Ingo Molnar
2010-08-24 19:06 Ingo Molnar
2010-08-19 14:55 Ingo Molnar
2010-08-18 8:14 Ingo Molnar
2010-07-23 19:41 Ingo Molnar
2010-07-16 17:30 Ingo Molnar
2010-07-08 4:36 Frederic Weisbecker
2010-07-08 4:40 ` Frederic Weisbecker
2010-07-08 6:36 ` Ingo Molnar
2010-07-04 20:24 Ingo Molnar
2010-06-10 10:25 Ingo Molnar
2010-06-02 12:28 Ingo Molnar
2010-05-31 23:02 Frederic Weisbecker
2010-06-01 6:59 ` Ingo Molnar
2010-05-30 19:27 Ingo Molnar
2010-05-20 9:44 Frederic Weisbecker
2010-05-20 12:40 ` Ingo Molnar
2010-05-11 19:18 Ingo Molnar
2010-05-12 0:39 ` Linus Torvalds
2010-04-06 17:49 Ingo Molnar
2010-04-04 10:15 Ingo Molnar
2010-04-03 10:47 Frederic Weisbecker
2010-03-28 5:11 Frederic Weisbecker
2010-03-29 3:33 ` Ingo Molnar
2010-03-26 15:16 Ingo Molnar
2010-03-16 16:06 Ingo Molnar
2010-03-11 19:12 Ingo Molnar
2010-02-22 16:50 Ingo Molnar
2010-02-22 17:01 ` Linus Torvalds
2010-02-22 17:15 ` Frederic Weisbecker
2010-02-14 9:06 Ingo Molnar
2010-01-31 17:32 Ingo Molnar
2010-01-21 15:38 Ingo Molnar
2009-12-31 12:00 Ingo Molnar
2009-12-18 18:59 Ingo Molnar
2009-09-22 7:51 Ingo Molnar
2009-09-22 14:49 ` Linus Torvalds
2009-09-22 14:59 ` Ingo Molnar
2009-09-22 15:13 ` Linus Torvalds
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