Merge branch 'misc' of master.kernel.org:/pub/scm/linux/kernel/git/galak/powerpc...

[sfrench/cifs-2.6.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 95ad7f8db3d619c7e8db61265a23d582a9a85738..1fbf466a29aab6ca0dfe1cf6e5d6ac16fba546d8 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -48,7 +48,7 @@
 static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
 static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
 
-DECLARE_MUTEX(kprobe_mutex);           /* Protects kprobe_table */
+DEFINE_MUTEX(kprobe_mutex);            /* Protects kprobe_table */
 DEFINE_SPINLOCK(kretprobe_lock);       /* Protects kretprobe_inst_table */
 static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
 
@@ -323,10 +323,10 @@ struct hlist_head __kprobes *kretprobe_inst_table_head(struct task_struct *tsk)
 }
 
 /*
- * This function is called from exit_thread or flush_thread when task tk's
- * stack is being recycled so that we can recycle any function-return probe
- * instances associated with this task. These left over instances represent
- * probed functions that have been called but will never return.
+ * This function is called from finish_task_switch when task tk becomes dead,
+ * so that we can recycle any function-return probe instances associated
+ * with this task. These left over instances represent probed functions
+ * that have been called but will never return.
  */
 void __kprobes kprobe_flush_task(struct task_struct *tk)
 {
@@ -336,7 +336,7 @@ void __kprobes kprobe_flush_task(struct task_struct *tk)
        unsigned long flags = 0;
 
        spin_lock_irqsave(&kretprobe_lock, flags);
-        head = kretprobe_inst_table_head(current);
+        head = kretprobe_inst_table_head(tk);
         hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
                 if (ri->task == tk)
                         recycle_rp_inst(ri);
@@ -460,7 +460,7 @@ static int __kprobes __register_kprobe(struct kprobe *p,
        }
 
        p->nmissed = 0;
-       down(&kprobe_mutex);
+       mutex_lock(&kprobe_mutex);
        old_p = get_kprobe(p->addr);
        if (old_p) {
                ret = register_aggr_kprobe(old_p, p);
@@ -477,7 +477,7 @@ static int __kprobes __register_kprobe(struct kprobe *p,
        arch_arm_kprobe(p);
 
 out:
-       up(&kprobe_mutex);
+       mutex_unlock(&kprobe_mutex);
 
        if (ret && probed_mod)
                module_put(probed_mod);
@@ -496,10 +496,10 @@ void __kprobes unregister_kprobe(struct kprobe *p)
        struct kprobe *old_p, *list_p;
        int cleanup_p;
 
-       down(&kprobe_mutex);
+       mutex_lock(&kprobe_mutex);
        old_p = get_kprobe(p->addr);
        if (unlikely(!old_p)) {
-               up(&kprobe_mutex);
+               mutex_unlock(&kprobe_mutex);
                return;
        }
        if (p != old_p) {
@@ -507,7 +507,7 @@ void __kprobes unregister_kprobe(struct kprobe *p)
                        if (list_p == p)
                        /* kprobe p is a valid probe */
                                goto valid_p;
-               up(&kprobe_mutex);
+               mutex_unlock(&kprobe_mutex);
                return;
        }
 valid_p:
@@ -523,7 +523,7 @@ valid_p:
                cleanup_p = 0;
        }
 
-       up(&kprobe_mutex);
+       mutex_unlock(&kprobe_mutex);
 
        synchronize_sched();
        if (p->mod_refcounted &&
@@ -585,6 +585,9 @@ int __kprobes register_kretprobe(struct kretprobe *rp)
        int i;
 
        rp->kp.pre_handler = pre_handler_kretprobe;
+       rp->kp.post_handler = NULL;
+       rp->kp.fault_handler = NULL;
+       rp->kp.break_handler = NULL;
 
        /* Pre-allocate memory for max kretprobe instances */
        if (rp->maxactive <= 0) {
@@ -631,12 +634,12 @@ void __kprobes unregister_kretprobe(struct kretprobe *rp)
        unregister_kprobe(&rp->kp);
        /* No race here */
        spin_lock_irqsave(&kretprobe_lock, flags);
-       free_rp_inst(rp);
        while ((ri = get_used_rp_inst(rp)) != NULL) {
                ri->rp = NULL;
                hlist_del(&ri->uflist);
        }
        spin_unlock_irqrestore(&kretprobe_lock, flags);
+       free_rp_inst(rp);
 }
 
 static int __init init_kprobes(void)