Merge remote branch 'airlied/drm-fixes' into drm-intel-fixes

[pandora-kernel.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 56a8919..9737a76 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -74,7 +74,8 @@ static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
 /* NOTE: change this value only with kprobe_mutex held */
 static bool kprobes_all_disarmed;
 
-static DEFINE_MUTEX(kprobe_mutex);     /* Protects kprobe_table */
+/* This protects kprobe_table and optimizing_list */
+static DEFINE_MUTEX(kprobe_mutex);
 static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
 static struct {
        spinlock_t lock ____cacheline_aligned_in_smp;
@@ -595,6 +596,7 @@ static __kprobes void try_to_optimize_kprobe(struct kprobe *p)
 }
 
 #ifdef CONFIG_SYSCTL
+/* This should be called with kprobe_mutex locked */
 static void __kprobes optimize_all_kprobes(void)
 {
        struct hlist_head *head;
@@ -607,17 +609,16 @@ static void __kprobes optimize_all_kprobes(void)
                return;
 
        kprobes_allow_optimization = true;
-       mutex_lock(&text_mutex);
        for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
                head = &kprobe_table[i];
                hlist_for_each_entry_rcu(p, node, head, hlist)
                        if (!kprobe_disabled(p))
                                optimize_kprobe(p);
        }
-       mutex_unlock(&text_mutex);
        printk(KERN_INFO "Kprobes globally optimized\n");
 }
 
+/* This should be called with kprobe_mutex locked */
 static void __kprobes unoptimize_all_kprobes(void)
 {
        struct hlist_head *head;
@@ -1144,14 +1145,13 @@ int __kprobes register_kprobe(struct kprobe *p)
        if (ret)
                return ret;
 
+       jump_label_lock();
        preempt_disable();
        if (!kernel_text_address((unsigned long) p->addr) ||
            in_kprobes_functions((unsigned long) p->addr) ||
            ftrace_text_reserved(p->addr, p->addr) ||
-           jump_label_text_reserved(p->addr, p->addr)) {
-               preempt_enable();
-               return -EINVAL;
-       }
+           jump_label_text_reserved(p->addr, p->addr))
+               goto fail_with_jump_label;
 
        /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
        p->flags &= KPROBE_FLAG_DISABLED;
@@ -1165,10 +1165,9 @@ int __kprobes register_kprobe(struct kprobe *p)
                 * We must hold a refcount of the probed module while updating
                 * its code to prohibit unexpected unloading.
                 */
-               if (unlikely(!try_module_get(probed_mod))) {
-                       preempt_enable();
-                       return -EINVAL;
-               }
+               if (unlikely(!try_module_get(probed_mod)))
+                       goto fail_with_jump_label;
+
                /*
                 * If the module freed .init.text, we couldn't insert
                 * kprobes in there.
@@ -1176,16 +1175,18 @@ int __kprobes register_kprobe(struct kprobe *p)
                if (within_module_init((unsigned long)p->addr, probed_mod) &&
                    probed_mod->state != MODULE_STATE_COMING) {
                        module_put(probed_mod);
-                       preempt_enable();
-                       return -EINVAL;
+                       goto fail_with_jump_label;
                }
        }
        preempt_enable();
+       jump_label_unlock();
 
        p->nmissed = 0;
        INIT_LIST_HEAD(&p->list);
        mutex_lock(&kprobe_mutex);
 
+       jump_label_lock(); /* needed to call jump_label_text_reserved() */
+
        get_online_cpus();      /* For avoiding text_mutex deadlock. */
        mutex_lock(&text_mutex);
 
@@ -1213,12 +1214,18 @@ int __kprobes register_kprobe(struct kprobe *p)
 out:
        mutex_unlock(&text_mutex);
        put_online_cpus();
+       jump_label_unlock();
        mutex_unlock(&kprobe_mutex);
 
        if (probed_mod)
                module_put(probed_mod);
 
        return ret;
+
+fail_with_jump_label:
+       preempt_enable();
+       jump_label_unlock();
+       return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(register_kprobe);