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-rw-r--r--arch/i386/kernel/kprobes.c35
-rw-r--r--arch/ia64/kernel/kprobes.c22
-rw-r--r--arch/ppc64/kernel/kprobes.c11
-rw-r--r--arch/sparc64/kernel/kprobes.c25
-rw-r--r--arch/x86_64/kernel/kprobes.c28
5 files changed, 65 insertions, 56 deletions
diff --git a/arch/i386/kernel/kprobes.c b/arch/i386/kernel/kprobes.c
index 6345b43..fd35039 100644
--- a/arch/i386/kernel/kprobes.c
+++ b/arch/i386/kernel/kprobes.c
@@ -158,8 +158,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
kprobe_opcode_t *addr = NULL;
unsigned long *lp;
- /* We're in an interrupt, but this is clear and BUG()-safe. */
- preempt_disable();
/* Check if the application is using LDT entry for its code segment and
* calculate the address by reading the base address from the LDT entry.
*/
@@ -232,6 +230,11 @@ static 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);
@@ -245,7 +248,6 @@ ss_probe:
return 1;
no_kprobe:
- preempt_enable_no_resched();
return ret;
}
@@ -313,11 +315,11 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
unlock_kprobes();
preempt_enable_no_resched();
- /*
- * By returning a non-zero value, we are telling
- * kprobe_handler() that we have handled unlocking
- * and re-enabling preemption.
- */
+ /*
+ * By returning a non-zero value, we are telling
+ * kprobe_handler() that we have handled unlocking
+ * and re-enabling preemption
+ */
return 1;
}
@@ -453,29 +455,29 @@ 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)
@@ -502,7 +504,6 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
void __kprobes jprobe_return(void)
{
- preempt_enable_no_resched();
asm volatile (" xchgl %%ebx,%%esp \n"
" int3 \n"
" .globl jprobe_return_end \n"
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 471086b..1e80ec8 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -395,7 +395,7 @@ 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;
}
@@ -607,8 +607,6 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
struct pt_regs *regs = args->regs;
kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
- preempt_disable();
-
/* Handle recursion cases */
if (kprobe_running()) {
p = get_kprobe(addr);
@@ -665,6 +663,11 @@ static int __kprobes pre_kprobes_handler(struct die_args *args)
goto no_kprobe;
}
+ /*
+ * This preempt_disable() matches the preempt_enable_no_resched()
+ * in post_kprobes_handler()
+ */
+ preempt_disable();
kprobe_status = KPROBE_HIT_ACTIVE;
set_current_kprobe(p);
@@ -682,7 +685,6 @@ ss_probe:
return 1;
no_kprobe:
- preempt_enable_no_resched();
return ret;
}
@@ -733,22 +735,26 @@ 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_BREAK:
if (pre_kprobes_handler(args))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
case DIE_SS:
if (post_kprobes_handler(args->regs))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
case DIE_PAGE_FAULT:
if (kprobes_fault_handler(args->regs, args->trapnr))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
default:
break;
}
- return NOTIFY_DONE;
+ preempt_enable();
+ return ret;
}
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
diff --git a/arch/ppc64/kernel/kprobes.c b/arch/ppc64/kernel/kprobes.c
index ed876a5..6071ee9 100644
--- a/arch/ppc64/kernel/kprobes.c
+++ b/arch/ppc64/kernel/kprobes.c
@@ -209,6 +209,11 @@ static inline int 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;
current_kprobe = p;
kprobe_saved_msr = regs->msr;
@@ -219,11 +224,6 @@ static inline int kprobe_handler(struct pt_regs *regs)
ss_probe:
prepare_singlestep(p, regs);
kprobe_status = KPROBE_HIT_SS;
- /*
- * This preempt_disable() matches the preempt_enable_no_resched()
- * in post_kprobe_handler().
- */
- preempt_disable();
return 1;
no_kprobe:
@@ -293,6 +293,7 @@ int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
regs->nip = orig_ret_address;
unlock_kprobes();
+ preempt_enable_no_resched();
/*
* By returning a non-zero value, we are telling
diff --git a/arch/sparc64/kernel/kprobes.c b/arch/sparc64/kernel/kprobes.c
index 0d66d07..755a0d7 100644
--- a/arch/sparc64/kernel/kprobes.c
+++ b/arch/sparc64/kernel/kprobes.c
@@ -118,8 +118,6 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
void *addr = (void *) regs->tpc;
int ret = 0;
- preempt_disable();
-
if (kprobe_running()) {
/* We *are* holding lock here, so this is safe.
* Disarm the probe we just hit, and ignore it.
@@ -171,6 +169,11 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
goto no_kprobe;
}
+ /*
+ * This preempt_disable() matches the preempt_enable_no_resched()
+ * in post_kprobes_handler()
+ */
+ preempt_disable();
set_current_kprobe(p, regs);
kprobe_status = KPROBE_HIT_ACTIVE;
if (p->pre_handler && p->pre_handler(p, regs))
@@ -182,7 +185,6 @@ ss_probe:
return 1;
no_kprobe:
- preempt_enable_no_resched();
return ret;
}
@@ -322,29 +324,29 @@ 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_DEBUG:
if (kprobe_handler(args->regs))
- return NOTIFY_STOP;
+ ret = NOTIFY_STOP;
break;
case DIE_DEBUG_2:
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;
}
asmlinkage void __kprobes kprobe_trap(unsigned long trap_level,
@@ -396,7 +398,6 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
void __kprobes jprobe_return(void)
{
- preempt_enable_no_resched();
__asm__ __volatile__(
".globl jprobe_return_trap_instruction\n"
"jprobe_return_trap_instruction:\n\t"
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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