[PATCH] mutex subsystem, debugging code

[powerpc.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 5beda37..3bb71e6 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -246,6 +246,19 @@ static int __kprobes aggr_break_handler(struct kprobe *p, struct pt_regs *regs)
        return ret;
 }
 
+/* Walks the list and increments nmissed count for multiprobe case */
+void __kprobes kprobes_inc_nmissed_count(struct kprobe *p)
+{
+       struct kprobe *kp;
+       if (p->pre_handler != aggr_pre_handler) {
+               p->nmissed++;
+       } else {
+               list_for_each_entry_rcu(kp, &p->list, list)
+                       kp->nmissed++;
+       }
+       return;
+}
+
 /* Called with kretprobe_lock held */
 struct kretprobe_instance __kprobes *get_free_rp_inst(struct kretprobe *rp)
 {
@@ -399,10 +412,7 @@ static inline void add_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
        INIT_LIST_HEAD(&ap->list);
        list_add_rcu(&p->list, &ap->list);
 
-       INIT_HLIST_NODE(&ap->hlist);
-       hlist_del_rcu(&p->hlist);
-       hlist_add_head_rcu(&ap->hlist,
-               &kprobe_table[hash_ptr(ap->addr, KPROBE_HASH_BITS)]);
+       hlist_replace_rcu(&p->hlist, &ap->hlist);
 }
 
 /*
@@ -462,9 +472,16 @@ int __kprobes register_kprobe(struct kprobe *p)
        int ret = 0;
        unsigned long flags = 0;
        struct kprobe *old_p;
+       struct module *mod;
+
+       if ((!kernel_text_address((unsigned long) p->addr)) ||
+               in_kprobes_functions((unsigned long) p->addr))
+               return -EINVAL;
+
+       if ((mod = module_text_address((unsigned long) p->addr)) &&
+                       (unlikely(!try_module_get(mod))))
+               return -EINVAL;
 
-       if ((ret = in_kprobes_functions((unsigned long) p->addr)) != 0)
-               return ret;
        if ((ret = arch_prepare_kprobe(p)) != 0)
                goto rm_kprobe;
 
@@ -488,6 +505,8 @@ out:
 rm_kprobe:
        if (ret == -EEXIST)
                arch_remove_kprobe(p);
+       if (ret && mod)
+               module_put(mod);
        return ret;
 }
 
@@ -495,6 +514,7 @@ void __kprobes unregister_kprobe(struct kprobe *p)
 {
        unsigned long flags;
        struct kprobe *old_p;
+       struct module *mod;
 
        spin_lock_irqsave(&kprobe_lock, flags);
        old_p = get_kprobe(p->addr);
@@ -506,6 +526,10 @@ void __kprobes unregister_kprobe(struct kprobe *p)
                        cleanup_kprobe(p, flags);
 
                synchronize_sched();
+
+               if ((mod = module_text_address((unsigned long)p->addr)))
+                       module_put(mod);
+
                if (old_p->pre_handler == aggr_pre_handler &&
                                list_empty(&old_p->list))
                        kfree(old_p);