2.6.24-rc3

 kernel

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 4b8a449..e3a5d81 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -64,7 +64,6 @@
 
 static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
 static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
-static atomic_t kprobe_count;
 
 /* NOTE: change this value only with kprobe_mutex held */
 static bool kprobe_enabled;
@@ -73,11 +72,6 @@ DEFINE_MUTEX(kprobe_mutex);      /* Protects kprobe_table */
 DEFINE_SPINLOCK(kretprobe_lock);   /* Protects kretprobe_inst_table */
 static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
 
-static struct notifier_block kprobe_page_fault_nb = {
-   .notifier_call = kprobe_exceptions_notify,
-   .priority = 0x7fffffff /* we need to notified first */
-};
-
 #ifdef __ARCH_WANT_KPROBES_INSN_SLOT
 /*
  * kprobe->ainsn.insn points to the copy of the instruction to be
@@ -556,8 +550,6 @@ static int __kprobes __register_kprobe(struct kprobe *p,
    old_p = get_kprobe(p->addr);
    if (old_p) {
       ret = register_aggr_kprobe(old_p, p);
-      if (!ret)
-         atomic_inc(&kprobe_count);
       goto out;
    }
 
@@ -569,13 +561,9 @@ static int __kprobes __register_kprobe(struct kprobe *p,
    hlist_add_head_rcu(&p->hlist,
              &kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
 
-   if (kprobe_enabled) {
-      if (atomic_add_return(1, &kprobe_count) == \
-            (ARCH_INACTIVE_KPROBE_COUNT + 1))
-         register_page_fault_notifier(&kprobe_page_fault_nb);
-
+   if (kprobe_enabled)
       arch_arm_kprobe(p);
-   }
+
 out:
    mutex_unlock(&kprobe_mutex);
 
@@ -658,16 +646,6 @@ valid_p:
       }
       mutex_unlock(&kprobe_mutex);
    }
-
-   /* Call unregister_page_fault_notifier()
-    * if no probes are active
-    */
-   mutex_lock(&kprobe_mutex);
-   if (atomic_add_return(-1, &kprobe_count) == \
-            ARCH_INACTIVE_KPROBE_COUNT)
-      unregister_page_fault_notifier(&kprobe_page_fault_nb);
-   mutex_unlock(&kprobe_mutex);
-   return;
 }
 
 static struct notifier_block kprobe_exceptions_nb = {
@@ -738,6 +716,18 @@ int __kprobes register_kretprobe(struct kretprobe *rp)
    int ret = 0;
    struct kretprobe_instance *inst;
    int i;
+   void *addr = rp->kp.addr;
+
+   if (kretprobe_blacklist_size) {
+      if (addr == NULL)
+         kprobe_lookup_name(rp->kp.symbol_name, addr);
+      addr += rp->kp.offset;
+
+      for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+         if (kretprobe_blacklist[i].addr == addr)
+            return -EINVAL;
+      }
+   }
 
    rp->kp.pre_handler = pre_handler_kretprobe;
    rp->kp.post_handler = NULL;
@@ -815,7 +805,17 @@ static int __init init_kprobes(void)
       INIT_HLIST_HEAD(&kprobe_table[i]);
       INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
    }
-   atomic_set(&kprobe_count, 0);
+
+   if (kretprobe_blacklist_size) {
+      /* lookup the function address from its name */
+      for (i = 0; kretprobe_blacklist[i].name != NULL; i++) {
+         kprobe_lookup_name(kretprobe_blacklist[i].name,
+                  kretprobe_blacklist[i].addr);
+         if (!kretprobe_blacklist[i].addr)
+            printk("kretprobe: lookup failed: %s\n",
+                   kretprobe_blacklist[i].name);
+      }
+   }
 
    /* By default, kprobes are enabled */
    kprobe_enabled = true;
@@ -921,13 +921,6 @@ static void __kprobes enable_all_kprobes(void)
    if (kprobe_enabled)
       goto already_enabled;
 
-   /*
-    * Re-register the page fault notifier only if there are any
-    * active probes at the time of enabling kprobes globally
-    */
-   if (atomic_read(&kprobe_count) > ARCH_INACTIVE_KPROBE_COUNT)
-      register_page_fault_notifier(&kprobe_page_fault_nb);
-
    for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
       head = &kprobe_table[i];
       hlist_for_each_entry_rcu(p, node, head, hlist)
@@ -968,10 +961,7 @@ static void __kprobes disable_all_kprobes(void)
    mutex_unlock(&kprobe_mutex);
    /* Allow all currently running kprobes to complete */
    synchronize_sched();
-
-   mutex_lock(&kprobe_mutex);
-   /* Unconditionally unregister the page_fault notifier */
-   unregister_page_fault_notifier(&kprobe_page_fault_nb);
+   return;
 
 already_disabled:
    mutex_unlock(&kprobe_mutex);