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| author | Nicholas Piggin <npiggin@gmail.com> | 2016-09-16 12:48:08 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2016-09-19 02:53:54 +0200 |
| commit | 03465f899bdac70d34f6ca447a74d8ae9e284ce5 (patch) | |
| tree | 5822e3b95e15197b2ea837dca99da30342c7b618 /arch/powerpc/kernel/hw_breakpoint.c | |
| parent | powerpc: Set used_(vsr|vr|spe) in sigreturn path when MSR bits are active (diff) | |
| download | linux-03465f899bdac70d34f6ca447a74d8ae9e284ce5.tar.xz linux-03465f899bdac70d34f6ca447a74d8ae9e284ce5.zip | |
powerpc: Use kprobe blacklist for exception handlers
Currently we mark the C implementations of some exception handlers as
__kprobes. This has the effect of putting them in the ".kprobes.text"
section, which separates them from the rest of the text.
Instead we can use the blacklist macros to add the symbols to a
blacklist which kprobes will check. This allows the linker to move
exception handler functions close to callers and avoids trampolines in
larger kernels.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Reword change log a bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/hw_breakpoint.c')
| -rw-r--r-- | arch/powerpc/kernel/hw_breakpoint.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c index aec9a1b1d25b..9781c69eae57 100644 --- a/arch/powerpc/kernel/hw_breakpoint.c +++ b/arch/powerpc/kernel/hw_breakpoint.c @@ -206,7 +206,7 @@ void thread_change_pc(struct task_struct *tsk, struct pt_regs *regs) /* * Handle debug exception notifications. */ -int __kprobes hw_breakpoint_handler(struct die_args *args) +int hw_breakpoint_handler(struct die_args *args) { int rc = NOTIFY_STOP; struct perf_event *bp; @@ -290,11 +290,12 @@ out: rcu_read_unlock(); return rc; } +NOKPROBE_SYMBOL(hw_breakpoint_handler); /* * Handle single-step exceptions following a DABR hit. */ -static int __kprobes single_step_dabr_instruction(struct die_args *args) +static int single_step_dabr_instruction(struct die_args *args) { struct pt_regs *regs = args->regs; struct perf_event *bp = NULL; @@ -329,11 +330,12 @@ static int __kprobes single_step_dabr_instruction(struct die_args *args) return NOTIFY_STOP; } +NOKPROBE_SYMBOL(single_step_dabr_instruction); /* * Handle debug exception notifications. */ -int __kprobes hw_breakpoint_exceptions_notify( +int hw_breakpoint_exceptions_notify( struct notifier_block *unused, unsigned long val, void *data) { int ret = NOTIFY_DONE; @@ -349,6 +351,7 @@ int __kprobes hw_breakpoint_exceptions_notify( return ret; } +NOKPROBE_SYMBOL(hw_breakpoint_exceptions_notify); /* * Release the user breakpoints used by ptrace |