diff options
| author | Kumar Gala <galak@kernel.crashing.org> | 2008-06-26 01:57:58 -0500 |
|---|---|---|
| committer | Kumar Gala <galak@kernel.crashing.org> | 2008-06-26 03:35:33 -0500 |
| commit | b76e59d1fb086c2fdac5d243e09786d6581f2026 (patch) | |
| tree | 94348c544cc2c7b26ab0c5aa75b93c89e959a17e | |
| parent | d14b3dd6190af7ce4f88be68f8df828af6d44584 (diff) | |
powerpc/kprobes: Some minor fixes
* Mark __flush_icache_range as a function that can't be probed since its
used by the kprobe code.
* Fix an issue with single stepping and async exceptions. We need to
ensure that we dont get an async exception (external, decrementer, etc)
while we are attempting to single step the probe point.
Added a check to ensure we only handle a single step if its really
intended for the instruction in question.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/kernel/kprobes.c | 9 | ||||
| -rw-r--r-- | arch/powerpc/kernel/misc_32.S | 2 |
2 files changed, 10 insertions, 1 deletions
diff --git a/arch/powerpc/kernel/kprobes.c b/arch/powerpc/kernel/kprobes.c index 23545a2f51f..74693d91731 100644 --- a/arch/powerpc/kernel/kprobes.c +++ b/arch/powerpc/kernel/kprobes.c @@ -95,6 +95,11 @@ void __kprobes arch_remove_kprobe(struct kprobe *p) static void __kprobes prepare_singlestep(struct kprobe *p, struct pt_regs *regs) { + /* We turn off async exceptions to ensure that the single step will + * be for the instruction we have the kprobe on, if we dont its + * possible we'd get the single step reported for an exception handler + * like Decrementer or External Interrupt */ + regs->msr &= ~MSR_EE; regs->msr |= MSR_SE; /* @@ -376,6 +381,10 @@ static int __kprobes post_kprobe_handler(struct pt_regs *regs) if (!cur) return 0; + /* make sure we got here for instruction we have a kprobe on */ + if (((unsigned long)cur->ainsn.insn + 4) != regs->nip) + return 0; + if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) { kcb->kprobe_status = KPROBE_HIT_SSDONE; cur->post_handler(cur, regs, 0); diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S index 89aaaa6f356..6321ae36f72 100644 --- a/arch/powerpc/kernel/misc_32.S +++ b/arch/powerpc/kernel/misc_32.S @@ -489,7 +489,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE) * * flush_icache_range(unsigned long start, unsigned long stop) */ -_GLOBAL(__flush_icache_range) +_KPROBE(__flush_icache_range) BEGIN_FTR_SECTION blr /* for 601, do nothing */ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE) |