From: James Morse <james.morse@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: Mark Rutland <mark.rutland@arm.com>,
Catalin Marinas <catalin.marinas@arm.com>,
James Morse <james.morse@arm.com>,
Masami Hiramatsu <mhiramat@kernel.org>,
Will Deacon <will@kernel.org>,
Julien Thierry <julien.thierry.kdev@gmail.com>
Subject: [PATCH 2/8] arm64: remove __exception annotations
Date: Thu, 3 Oct 2019 18:16:36 +0100 [thread overview]
Message-ID: <20191003171642.135652-3-james.morse@arm.com> (raw)
In-Reply-To: <20191003171642.135652-1-james.morse@arm.com>
Since commit 732674980139 ("arm64: unwind: reference pt_regs via embedded
stack frame") arm64 has has not used the __exception annotation to dump
the pt_regs during stack tracing. in_exception_text() has no callers.
This annotation is only used to blacklist kprobes, it means the same as
__kprobes.
Section annotations like this require the functions to be grouped
together between the start/end markers, and placed according to
the linker script. For kprobes we also have NOKPROBE_SYMBOL() which
logs the symbol address in a section that kprobes parses and
blacklists at boot.
Using NOKPROBE_SYMBOL() instead lets kprobes publish the list of
blacklisted symbols, and saves us from having an arm64 specific
spelling of __kprobes.
Signed-off-by: James Morse <james.morse@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
---
(__exception_irq_entry means no-kprobes and optionally in a section
ftrace can use to pretty-print interrupt handler boundaries.)
---
arch/arm64/include/asm/exception.h | 4 ++--
arch/arm64/include/asm/traps.h | 10 ---------
arch/arm64/kernel/probes/kprobes.c | 4 ----
arch/arm64/kernel/traps.c | 10 ++++++---
arch/arm64/kernel/vmlinux.lds.S | 3 ---
arch/arm64/mm/fault.c | 34 +++++++++++++++---------------
6 files changed, 26 insertions(+), 39 deletions(-)
diff --git a/arch/arm64/include/asm/exception.h b/arch/arm64/include/asm/exception.h
index a17393ff6677..b0b3ba56e919 100644
--- a/arch/arm64/include/asm/exception.h
+++ b/arch/arm64/include/asm/exception.h
@@ -8,14 +8,14 @@
#define __ASM_EXCEPTION_H
#include <asm/esr.h>
+#include <asm/kprobes.h>
#include <linux/interrupt.h>
-#define __exception __attribute__((section(".exception.text")))
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
#define __exception_irq_entry __irq_entry
#else
-#define __exception_irq_entry __exception
+#define __exception_irq_entry __kprobes
#endif
static inline u32 disr_to_esr(u64 disr)
diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index 59690613ac31..cee5928e1b7d 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -42,16 +42,6 @@ static inline int __in_irqentry_text(unsigned long ptr)
ptr < (unsigned long)&__irqentry_text_end;
}
-static inline int in_exception_text(unsigned long ptr)
-{
- int in;
-
- in = ptr >= (unsigned long)&__exception_text_start &&
- ptr < (unsigned long)&__exception_text_end;
-
- return in ? : __in_irqentry_text(ptr);
-}
-
static inline int in_entry_text(unsigned long ptr)
{
return ptr >= (unsigned long)&__entry_text_start &&
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index c4452827419b..d1c95dcf1d78 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -455,10 +455,6 @@ int __init arch_populate_kprobe_blacklist(void)
(unsigned long)__irqentry_text_end);
if (ret)
return ret;
- ret = kprobe_add_area_blacklist((unsigned long)__exception_text_start,
- (unsigned long)__exception_text_end);
- if (ret)
- return ret;
ret = kprobe_add_area_blacklist((unsigned long)__idmap_text_start,
(unsigned long)__idmap_text_end);
if (ret)
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 34739e80211b..ba1a571a7774 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -35,6 +35,7 @@
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/insn.h>
+#include <asm/kprobes.h>
#include <asm/traps.h>
#include <asm/smp.h>
#include <asm/stack_pointer.h>
@@ -393,7 +394,7 @@ void arm64_notify_segfault(unsigned long addr)
force_signal_inject(SIGSEGV, code, addr);
}
-asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
+asmlinkage void do_undefinstr(struct pt_regs *regs)
{
/* check for AArch32 breakpoint instructions */
if (!aarch32_break_handler(regs))
@@ -405,6 +406,7 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs)
BUG_ON(!user_mode(regs));
force_signal_inject(SIGILL, ILL_ILLOPC, regs->pc);
}
+NOKPROBE_SYMBOL(do_undefinstr);
#define __user_cache_maint(insn, address, res) \
if (address >= user_addr_max()) { \
@@ -667,7 +669,7 @@ static const struct sys64_hook cp15_64_hooks[] = {
{},
};
-asmlinkage void __exception do_cp15instr(unsigned int esr, struct pt_regs *regs)
+asmlinkage void do_cp15instr(unsigned int esr, struct pt_regs *regs)
{
const struct sys64_hook *hook, *hook_base;
@@ -705,9 +707,10 @@ asmlinkage void __exception do_cp15instr(unsigned int esr, struct pt_regs *regs)
*/
do_undefinstr(regs);
}
+NOKPROBE_SYMBOL(do_cp15instr);
#endif
-asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs)
+asmlinkage void do_sysinstr(unsigned int esr, struct pt_regs *regs)
{
const struct sys64_hook *hook;
@@ -724,6 +727,7 @@ asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs)
*/
do_undefinstr(regs);
}
+NOKPROBE_SYMBOL(do_sysinstr);
static const char *esr_class_str[] = {
[0 ... ESR_ELx_EC_MAX] = "UNRECOGNIZED EC",
diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index aa76f7259668..009057517bdd 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -111,9 +111,6 @@ SECTIONS
}
.text : { /* Real text segment */
_stext = .; /* Text and read-only data */
- __exception_text_start = .;
- *(.exception.text)
- __exception_text_end = .;
IRQENTRY_TEXT
SOFTIRQENTRY_TEXT
ENTRY_TEXT
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 115d7a0e4b08..ba62098de920 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -33,6 +33,7 @@
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/kasan.h>
+#include <asm/kprobes.h>
#include <asm/sysreg.h>
#include <asm/system_misc.h>
#include <asm/pgtable.h>
@@ -723,8 +724,8 @@ static const struct fault_info fault_info[] = {
{ do_bad, SIGKILL, SI_KERNEL, "unknown 63" },
};
-asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
- struct pt_regs *regs)
+asmlinkage void do_mem_abort(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs)
{
const struct fault_info *inf = esr_to_fault_info(esr);
@@ -740,16 +741,17 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
arm64_notify_die(inf->name, regs,
inf->sig, inf->code, (void __user *)addr, esr);
}
+NOKPROBE_SYMBOL(do_mem_abort);
-asmlinkage void __exception do_el0_irq_bp_hardening(void)
+asmlinkage void do_el0_irq_bp_hardening(void)
{
/* PC has already been checked in entry.S */
arm64_apply_bp_hardening();
}
+NOKPROBE_SYMBOL(do_el0_irq_bp_hardening);
-asmlinkage void __exception do_el0_ia_bp_hardening(unsigned long addr,
- unsigned int esr,
- struct pt_regs *regs)
+asmlinkage void do_el0_ia_bp_hardening(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs)
{
/*
* We've taken an instruction abort from userspace and not yet
@@ -762,11 +764,10 @@ asmlinkage void __exception do_el0_ia_bp_hardening(unsigned long addr,
local_daif_restore(DAIF_PROCCTX);
do_mem_abort(addr, esr, regs);
}
+NOKPROBE_SYMBOL(do_el0_ia_bp_hardening);
-
-asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
- unsigned int esr,
- struct pt_regs *regs)
+asmlinkage void do_sp_pc_abort(unsigned long addr, unsigned int esr,
+ struct pt_regs *regs)
{
if (user_mode(regs)) {
if (!is_ttbr0_addr(instruction_pointer(regs)))
@@ -777,6 +778,7 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
arm64_notify_die("SP/PC alignment exception", regs,
SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
}
+NOKPROBE_SYMBOL(do_sp_pc_abort);
int __init early_brk64(unsigned long addr, unsigned int esr,
struct pt_regs *regs);
@@ -859,8 +861,7 @@ NOKPROBE_SYMBOL(debug_exception_exit);
#ifdef CONFIG_ARM64_ERRATUM_1463225
DECLARE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa);
-static int __exception
-cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
{
if (user_mode(regs))
return 0;
@@ -879,16 +880,15 @@ cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
return 1;
}
#else
-static int __exception
-cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
+static int cortex_a76_erratum_1463225_debug_handler(struct pt_regs *regs)
{
return 0;
}
#endif /* CONFIG_ARM64_ERRATUM_1463225 */
+NOKPROBE_SYMBOL(cortex_a76_erratum_1463225_debug_handler);
-asmlinkage void __exception do_debug_exception(unsigned long addr_if_watchpoint,
- unsigned int esr,
- struct pt_regs *regs)
+asmlinkage void do_debug_exception(unsigned long addr_if_watchpoint,
+ unsigned int esr, struct pt_regs *regs)
{
const struct fault_info *inf = esr_to_debug_fault_info(esr);
unsigned long pc = instruction_pointer(regs);
--
2.20.1
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next prev parent reply other threads:[~2019-10-03 17:17 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-03 17:16 [PATCH 0/8] arm64: Convert entry.S synchronous exception handling to C James Morse
2019-10-03 17:16 ` [PATCH 1/8] arm64: Fix incorrect irqflag restore for priority masking for compat James Morse
2019-10-03 17:16 ` James Morse [this message]
2019-10-04 10:17 ` [PATCH 2/8] arm64: remove __exception annotations Mark Rutland
2019-10-04 14:10 ` Masami Hiramatsu
2019-10-04 16:08 ` James Morse
2019-10-04 16:34 ` Mark Rutland
2019-10-04 13:03 ` Marc Gonzalez
2019-10-04 16:08 ` James Morse
2019-10-03 17:16 ` [PATCH 3/8] arm64: Add prototypes for functions called by entry.S James Morse
2019-10-04 10:22 ` Mark Rutland
2019-10-03 17:16 ` [PATCH 4/8] arm64: add local_daif_inherit() James Morse
2019-10-03 17:16 ` [PATCH 5/8] arm64: entry: convert el1_sync to C James Morse
2019-10-04 10:39 ` Mark Rutland
2019-10-03 17:16 ` [PATCH 6/8] arm64: entry: convert el0_sync " James Morse
2019-10-04 12:57 ` Mark Rutland
2019-10-04 16:09 ` James Morse
2019-10-04 16:37 ` Mark Rutland
2019-10-03 17:16 ` [PATCH 7/8] arm64: Remove asmlinkage from updated functions James Morse
2019-10-04 12:58 ` Mark Rutland
2019-10-03 17:16 ` [PATCH 8/8] arm64: entry-common: don't touch daif before bp-hardening James Morse
2019-10-04 13:31 ` Mark Rutland
2019-10-04 16:09 ` James Morse
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