[FIX] kprobe and kretprobe disarming synchronization

Guarantee that other CPUs not handle breakpoints right now.

Change-Id: Ida84022387285ab71938f5f679d47a8a45a62d01
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>

diff --git a/kprobe/swap_kprobes.c b/kprobe/swap_kprobes.c
index 8a92c2b..7f11152 100644 (file)
--- a/kprobe/swap_kprobes.c
+++ b/kprobe/swap_kprobes.c
@@ -585,6 +585,11 @@ static void swap_unregister_valid_kprobe(struct kprobe *p, struct kprobe *old_p)
            (p->list.next == &old_p->list) && (p->list.prev == &old_p->list))) {
                /* Only probe on the hash list */
                swap_arch_disarm_kprobe(p);
+
+               /* FIXME: move sync out from atomic context */
+               if (!in_atomic())
+                       synchronize_sched();
+
                hlist_del_rcu(&old_p->hlist);
                remove_kprobe(old_p);
 
@@ -943,13 +948,14 @@ static int __swap_unregister_kretprobes_top(void *data)
        unsigned long flags;
        const size_t end = ((size_t) 0) - 1;
 
-       spin_lock_irqsave(&kretprobe_lock, flags);
        for (--size; size != end; --size) {
                swap_unregister_kprobe(&rps[size]->kp);
-               if (rp_disarm)
+               if (rp_disarm) {
+                       spin_lock_irqsave(&kretprobe_lock, flags);
                        swap_disarm_krp(rps[size]);
+                       spin_unlock_irqrestore(&kretprobe_lock, flags);
+               }
        }
-       spin_unlock_irqrestore(&kretprobe_lock, flags);
 
        return 0;
 }