[PATCH] Kprobes: rearrange preempt_disable/enable() calls

[platform/kernel/linux-arm64.git] / arch / ia64 / kernel / kprobes.c

diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index 471086b..1e80ec8 100644 (file)
--- 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)