static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
-static DEFINE_SPINLOCK(kprobe_lock); /* Protects kprobe_table */
+DECLARE_MUTEX(kprobe_mutex); /* Protects kprobe_table */
DEFINE_SPINLOCK(kretprobe_lock); /* Protects kretprobe_inst_table */
static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
+#ifdef __ARCH_WANT_KPROBES_INSN_SLOT
/*
* kprobe->ainsn.insn points to the copy of the instruction to be
* single-stepped. x86_64, POWER4 and above have no-exec support and
}
}
}
+#endif
/* We have preemption disabled.. so it is safe to use __ versions */
static inline void set_kprobe_instance(struct kprobe *kp)
/*
* This routine is called either:
- * - under the kprobe_lock spinlock - during kprobe_[un]register()
+ * - under the kprobe_mutex - during kprobe_[un]register()
* OR
* - with preemption disabled - from arch/xxx/kernel/kprobes.c
*/
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)
{
/*
* This is the second or subsequent kprobe at the address - handle
* the intricacies
- * TODO: Move kcalloc outside the spin_lock
*/
static int __kprobes register_aggr_kprobe(struct kprobe *old_p,
struct kprobe *p)
copy_kprobe(old_p, p);
ret = add_new_kprobe(old_p, p);
} else {
- ap = kcalloc(1, sizeof(struct kprobe), GFP_ATOMIC);
+ ap = kzalloc(sizeof(struct kprobe), GFP_KERNEL);
if (!ap)
return -ENOMEM;
add_aggr_kprobe(ap, old_p);
return ret;
}
-/* kprobe removal house-keeping routines */
-static inline void cleanup_kprobe(struct kprobe *p, unsigned long flags)
-{
- arch_disarm_kprobe(p);
- hlist_del_rcu(&p->hlist);
- spin_unlock_irqrestore(&kprobe_lock, flags);
- arch_remove_kprobe(p);
-}
-
-static inline void cleanup_aggr_kprobe(struct kprobe *old_p,
- struct kprobe *p, unsigned long flags)
-{
- list_del_rcu(&p->list);
- if (list_empty(&old_p->list))
- cleanup_kprobe(old_p, flags);
- else
- spin_unlock_irqrestore(&kprobe_lock, flags);
-}
-
static int __kprobes in_kprobes_functions(unsigned long addr)
{
if (addr >= (unsigned long)__kprobes_text_start
int __kprobes register_kprobe(struct kprobe *p)
{
int ret = 0;
- unsigned long flags = 0;
struct kprobe *old_p;
struct module *mod;
(unlikely(!try_module_get(mod))))
return -EINVAL;
- if ((ret = arch_prepare_kprobe(p)) != 0)
- goto rm_kprobe;
-
p->nmissed = 0;
- spin_lock_irqsave(&kprobe_lock, flags);
+ down(&kprobe_mutex);
old_p = get_kprobe(p->addr);
if (old_p) {
ret = register_aggr_kprobe(old_p, p);
goto out;
}
- arch_copy_kprobe(p);
+ if ((ret = arch_prepare_kprobe(p)) != 0)
+ goto out;
+
INIT_HLIST_NODE(&p->hlist);
hlist_add_head_rcu(&p->hlist,
&kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
arch_arm_kprobe(p);
out:
- spin_unlock_irqrestore(&kprobe_lock, flags);
-rm_kprobe:
- if (ret == -EEXIST)
- arch_remove_kprobe(p);
+ up(&kprobe_mutex);
+
if (ret && mod)
module_put(mod);
return ret;
void __kprobes unregister_kprobe(struct kprobe *p)
{
- unsigned long flags;
- struct kprobe *old_p;
struct module *mod;
+ struct kprobe *old_p, *list_p;
+ int cleanup_p;
- spin_lock_irqsave(&kprobe_lock, flags);
+ down(&kprobe_mutex);
old_p = get_kprobe(p->addr);
- if (old_p) {
- /* cleanup_*_kprobe() does the spin_unlock_irqrestore */
- if (old_p->pre_handler == aggr_pre_handler)
- cleanup_aggr_kprobe(old_p, p, flags);
- else
- cleanup_kprobe(p, flags);
+ if (unlikely(!old_p)) {
+ up(&kprobe_mutex);
+ return;
+ }
+ if (p != old_p) {
+ list_for_each_entry_rcu(list_p, &old_p->list, list)
+ if (list_p == p)
+ /* kprobe p is a valid probe */
+ goto valid_p;
+ up(&kprobe_mutex);
+ return;
+ }
+valid_p:
+ if ((old_p == p) || ((old_p->pre_handler == aggr_pre_handler) &&
+ (p->list.next == &old_p->list) &&
+ (p->list.prev == &old_p->list))) {
+ /* Only probe on the hash list */
+ arch_disarm_kprobe(p);
+ hlist_del_rcu(&old_p->hlist);
+ cleanup_p = 1;
+ } else {
+ list_del_rcu(&p->list);
+ cleanup_p = 0;
+ }
- synchronize_sched();
+ up(&kprobe_mutex);
- if ((mod = module_text_address((unsigned long)p->addr)))
- module_put(mod);
+ 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))
+ if (cleanup_p) {
+ if (p != old_p) {
+ list_del_rcu(&p->list);
kfree(old_p);
- } else
- spin_unlock_irqrestore(&kprobe_lock, flags);
+ }
+ arch_remove_kprobe(p);
+ }
}
static struct notifier_block kprobe_exceptions_nb = {
projects / powerpc.git / blobdiff