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-rw-r--r--arch/x86_64/kernel/kprobes.c28
1 files changed, 14 insertions, 14 deletions
diff --git a/arch/x86_64/kernel/kprobes.c b/arch/x86_64/kernel/kprobes.c
index 76a28b0..ebfa2c9 100644
--- a/arch/x86_64/kernel/kprobes.c
+++ b/arch/x86_64/kernel/kprobes.c
@@ -302,9 +302,6 @@ int __kprobes kprobe_handler(struct pt_regs *regs)
int ret = 0;
kprobe_opcode_t *addr = (kprobe_opcode_t *)(regs->rip - sizeof(kprobe_opcode_t));
- /* We're in an interrupt, but this is clear and BUG()-safe. */
- preempt_disable();
-
/* Check we're not actually recursing */
if (kprobe_running()) {
/* We *are* holding lock here, so this is safe.
@@ -372,6 +369,11 @@ int __kprobes kprobe_handler(struct pt_regs *regs)
goto no_kprobe;
}
+ /*
+ * This preempt_disable() matches the preempt_enable_no_resched()
+ * in post_kprobe_handler()
+ */
+ preempt_disable();
kprobe_status = KPROBE_HIT_ACTIVE;
set_current_kprobe(p, regs);
@@ -385,7 +387,6 @@ ss_probe:
return 1;
no_kprobe:
- preempt_enable_no_resched();
return ret;
}
@@ -456,7 +457,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
/*
* By returning a non-zero value, we are telling
* kprobe_handler() that we have handled unlocking
- * and re-enabling preemption.
+ * and re-enabling preemption
*/
return 1;
}
@@ -599,29 +600,29 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
{
struct die_args *args = (struct die_args *)data;
+ int ret = NOTIFY_DONE;
+
+ preempt_disable();
switch (val) {
case DIE_INT3:
if (kprobe_handler(args->regs))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
case DIE_DEBUG:
if (post_kprobe_handler(args->regs))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
case DIE_GPF:
- if (kprobe_running() &&
- kprobe_fault_handler(args->regs, args->trapnr))
- return NOTIFY_STOP;
- break;
case DIE_PAGE_FAULT:
if (kprobe_running() &&
kprobe_fault_handler(args->regs, args->trapnr))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
default:
break;
}
- return NOTIFY_DONE;
+ preempt_enable();
+ return ret;
}
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
@@ -647,7 +648,6 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
void __kprobes jprobe_return(void)
{
- preempt_enable_no_resched();
asm volatile (" xchg %%rbx,%%rsp \n"
" int3 \n"
" .globl jprobe_return_end \n"
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