* <prasanna@in.ibm.com> added function-return probes.
*/
#include <linux/kprobes.h>
-#include <linux/spinlock.h>
#include <linux/hash.h>
#include <linux/init.h>
+#include <linux/slab.h>
#include <linux/module.h>
+#include <linux/moduleloader.h>
+#include <asm-generic/sections.h>
#include <asm/cacheflush.h>
#include <asm/errno.h>
#include <asm/kdebug.h>
static struct hlist_head kprobe_table[KPROBE_TABLE_SIZE];
static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE];
-unsigned int kprobe_cpu = NR_CPUS;
-static DEFINE_SPINLOCK(kprobe_lock);
-static struct kprobe *curr_kprobe;
+DEFINE_MUTEX(kprobe_mutex); /* Protects kprobe_table */
+DEFINE_SPINLOCK(kretprobe_lock); /* Protects kretprobe_inst_table */
+static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
-/* Locks kprobe: irqs must be disabled */
-void lock_kprobes(void)
+#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
+ * stepping on the instruction on a vmalloced/kmalloced/data page
+ * is a recipe for disaster
+ */
+#define INSNS_PER_PAGE (PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t)))
+
+struct kprobe_insn_page {
+ struct hlist_node hlist;
+ kprobe_opcode_t *insns; /* Page of instruction slots */
+ char slot_used[INSNS_PER_PAGE];
+ int nused;
+};
+
+static struct hlist_head kprobe_insn_pages;
+
+/**
+ * get_insn_slot() - Find a slot on an executable page for an instruction.
+ * We allocate an executable page if there's no room on existing ones.
+ */
+kprobe_opcode_t __kprobes *get_insn_slot(void)
{
- spin_lock(&kprobe_lock);
- kprobe_cpu = smp_processor_id();
+ struct kprobe_insn_page *kip;
+ struct hlist_node *pos;
+
+ hlist_for_each(pos, &kprobe_insn_pages) {
+ kip = hlist_entry(pos, struct kprobe_insn_page, hlist);
+ if (kip->nused < INSNS_PER_PAGE) {
+ int i;
+ for (i = 0; i < INSNS_PER_PAGE; i++) {
+ if (!kip->slot_used[i]) {
+ kip->slot_used[i] = 1;
+ kip->nused++;
+ return kip->insns + (i * MAX_INSN_SIZE);
+ }
+ }
+ /* Surprise! No unused slots. Fix kip->nused. */
+ kip->nused = INSNS_PER_PAGE;
+ }
+ }
+
+ /* All out of space. Need to allocate a new page. Use slot 0.*/
+ kip = kmalloc(sizeof(struct kprobe_insn_page), GFP_KERNEL);
+ if (!kip) {
+ return NULL;
+ }
+
+ /*
+ * Use module_alloc so this page is within +/- 2GB of where the
+ * kernel image and loaded module images reside. This is required
+ * so x86_64 can correctly handle the %rip-relative fixups.
+ */
+ kip->insns = module_alloc(PAGE_SIZE);
+ if (!kip->insns) {
+ kfree(kip);
+ return NULL;
+ }
+ INIT_HLIST_NODE(&kip->hlist);
+ hlist_add_head(&kip->hlist, &kprobe_insn_pages);
+ memset(kip->slot_used, 0, INSNS_PER_PAGE);
+ kip->slot_used[0] = 1;
+ kip->nused = 1;
+ return kip->insns;
}
-void unlock_kprobes(void)
+void __kprobes free_insn_slot(kprobe_opcode_t *slot)
{
- kprobe_cpu = NR_CPUS;
- spin_unlock(&kprobe_lock);
+ struct kprobe_insn_page *kip;
+ struct hlist_node *pos;
+
+ hlist_for_each(pos, &kprobe_insn_pages) {
+ kip = hlist_entry(pos, struct kprobe_insn_page, hlist);
+ if (kip->insns <= slot &&
+ slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) {
+ int i = (slot - kip->insns) / MAX_INSN_SIZE;
+ kip->slot_used[i] = 0;
+ kip->nused--;
+ if (kip->nused == 0) {
+ /*
+ * Page is no longer in use. Free it unless
+ * it's the last one. We keep the last one
+ * so as not to have to set it up again the
+ * next time somebody inserts a probe.
+ */
+ hlist_del(&kip->hlist);
+ if (hlist_empty(&kprobe_insn_pages)) {
+ INIT_HLIST_NODE(&kip->hlist);
+ hlist_add_head(&kip->hlist,
+ &kprobe_insn_pages);
+ } else {
+ module_free(NULL, kip->insns);
+ kfree(kip);
+ }
+ }
+ return;
+ }
+ }
+}
+#endif
+
+/* We have preemption disabled.. so it is safe to use __ versions */
+static inline void set_kprobe_instance(struct kprobe *kp)
+{
+ __get_cpu_var(kprobe_instance) = kp;
}
-/* You have to be holding the kprobe_lock */
-struct kprobe *get_kprobe(void *addr)
+static inline void reset_kprobe_instance(void)
+{
+ __get_cpu_var(kprobe_instance) = NULL;
+}
+
+/*
+ * This routine is called either:
+ * - under the kprobe_mutex - during kprobe_[un]register()
+ * OR
+ * - with preemption disabled - from arch/xxx/kernel/kprobes.c
+ */
+struct kprobe __kprobes *get_kprobe(void *addr)
{
struct hlist_head *head;
struct hlist_node *node;
+ struct kprobe *p;
head = &kprobe_table[hash_ptr(addr, KPROBE_HASH_BITS)];
- hlist_for_each(node, head) {
- struct kprobe *p = hlist_entry(node, struct kprobe, hlist);
+ hlist_for_each_entry_rcu(p, node, head, hlist) {
if (p->addr == addr)
return p;
}
* Aggregate handlers for multiple kprobes support - these handlers
* take care of invoking the individual kprobe handlers on p->list
*/
-static int aggr_pre_handler(struct kprobe *p, struct pt_regs *regs)
+static int __kprobes aggr_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kprobe *kp;
- list_for_each_entry(kp, &p->list, list) {
+ list_for_each_entry_rcu(kp, &p->list, list) {
if (kp->pre_handler) {
- curr_kprobe = kp;
- kp->pre_handler(kp, regs);
- curr_kprobe = NULL;
+ set_kprobe_instance(kp);
+ if (kp->pre_handler(kp, regs))
+ return 1;
}
+ reset_kprobe_instance();
}
return 0;
}
-static void aggr_post_handler(struct kprobe *p, struct pt_regs *regs,
- unsigned long flags)
+static void __kprobes aggr_post_handler(struct kprobe *p, struct pt_regs *regs,
+ unsigned long flags)
{
struct kprobe *kp;
- list_for_each_entry(kp, &p->list, list) {
+ list_for_each_entry_rcu(kp, &p->list, list) {
if (kp->post_handler) {
- curr_kprobe = kp;
+ set_kprobe_instance(kp);
kp->post_handler(kp, regs, flags);
- curr_kprobe = NULL;
+ reset_kprobe_instance();
}
}
return;
}
-static int aggr_fault_handler(struct kprobe *p, struct pt_regs *regs,
- int trapnr)
+static int __kprobes aggr_fault_handler(struct kprobe *p, struct pt_regs *regs,
+ int trapnr)
{
+ struct kprobe *cur = __get_cpu_var(kprobe_instance);
+
/*
* if we faulted "during" the execution of a user specified
* probe handler, invoke just that probe's fault handler
*/
- if (curr_kprobe && curr_kprobe->fault_handler) {
- if (curr_kprobe->fault_handler(curr_kprobe, regs, trapnr))
+ if (cur && cur->fault_handler) {
+ if (cur->fault_handler(cur, regs, trapnr))
return 1;
}
return 0;
}
-struct kprobe trampoline_p = {
- .addr = (kprobe_opcode_t *) &kretprobe_trampoline,
- .pre_handler = trampoline_probe_handler,
- .post_handler = trampoline_post_handler
-};
+static int __kprobes aggr_break_handler(struct kprobe *p, struct pt_regs *regs)
+{
+ struct kprobe *cur = __get_cpu_var(kprobe_instance);
+ int ret = 0;
-struct kretprobe_instance *get_free_rp_inst(struct kretprobe *rp)
+ if (cur && cur->break_handler) {
+ if (cur->break_handler(cur, regs))
+ ret = 1;
+ }
+ reset_kprobe_instance();
+ return ret;
+}
+
+/* Walks the list and increments nmissed count for multiprobe case */
+void __kprobes kprobes_inc_nmissed_count(struct kprobe *p)
{
- struct hlist_node *node;
- struct kretprobe_instance *ri;
- hlist_for_each_entry(ri, node, &rp->free_instances, uflist)
- return ri;
- return NULL;
+ 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;
}
-static struct kretprobe_instance *get_used_rp_inst(struct kretprobe *rp)
+/* Called with kretprobe_lock held */
+struct kretprobe_instance __kprobes *get_free_rp_inst(struct kretprobe *rp)
{
struct hlist_node *node;
struct kretprobe_instance *ri;
- hlist_for_each_entry(ri, node, &rp->used_instances, uflist)
+ hlist_for_each_entry(ri, node, &rp->free_instances, uflist)
return ri;
return NULL;
}
-struct kretprobe_instance *get_rp_inst(void *sara)
+/* Called with kretprobe_lock held */
+static struct kretprobe_instance __kprobes *get_used_rp_inst(struct kretprobe
+ *rp)
{
- struct hlist_head *head;
struct hlist_node *node;
- struct task_struct *tsk;
struct kretprobe_instance *ri;
-
- tsk = arch_get_kprobe_task(sara);
- head = &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)];
- hlist_for_each_entry(ri, node, head, hlist) {
- if (ri->stack_addr == sara)
- return ri;
- }
+ hlist_for_each_entry(ri, node, &rp->used_instances, uflist)
+ return ri;
return NULL;
}
-void add_rp_inst(struct kretprobe_instance *ri)
+/* Called with kretprobe_lock held */
+void __kprobes add_rp_inst(struct kretprobe_instance *ri)
{
- struct task_struct *tsk;
/*
* Remove rp inst off the free list -
* Add it back when probed function returns
*/
hlist_del(&ri->uflist);
- tsk = arch_get_kprobe_task(ri->stack_addr);
+
/* Add rp inst onto table */
INIT_HLIST_NODE(&ri->hlist);
hlist_add_head(&ri->hlist,
- &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)]);
+ &kretprobe_inst_table[hash_ptr(ri->task, KPROBE_HASH_BITS)]);
/* Also add this rp inst to the used list. */
INIT_HLIST_NODE(&ri->uflist);
hlist_add_head(&ri->uflist, &ri->rp->used_instances);
}
-void recycle_rp_inst(struct kretprobe_instance *ri)
+/* Called with kretprobe_lock held */
+void __kprobes recycle_rp_inst(struct kretprobe_instance *ri)
{
/* remove rp inst off the rprobe_inst_table */
hlist_del(&ri->hlist);
kfree(ri);
}
-struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk)
+struct hlist_head __kprobes *kretprobe_inst_table_head(struct task_struct *tsk)
{
return &kretprobe_inst_table[hash_ptr(tsk, KPROBE_HASH_BITS)];
}
-struct kretprobe_instance *get_rp_inst_tsk(struct task_struct *tk)
+/*
+ * 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)
{
- struct task_struct *tsk;
- struct hlist_head *head;
- struct hlist_node *node;
- struct kretprobe_instance *ri;
+ struct kretprobe_instance *ri;
+ struct hlist_head *head;
+ struct hlist_node *node, *tmp;
+ unsigned long flags = 0;
- head = &kretprobe_inst_table[hash_ptr(tk, KPROBE_HASH_BITS)];
+ spin_lock_irqsave(&kretprobe_lock, flags);
+ head = kretprobe_inst_table_head(tk);
+ hlist_for_each_entry_safe(ri, node, tmp, head, hlist) {
+ if (ri->task == tk)
+ recycle_rp_inst(ri);
+ }
+ spin_unlock_irqrestore(&kretprobe_lock, flags);
+}
- hlist_for_each_entry(ri, node, head, hlist) {
- tsk = arch_get_kprobe_task(ri->stack_addr);
- if (tsk == tk)
- return ri;
+static inline void free_rp_inst(struct kretprobe *rp)
+{
+ struct kretprobe_instance *ri;
+ while ((ri = get_free_rp_inst(rp)) != NULL) {
+ hlist_del(&ri->uflist);
+ kfree(ri);
}
- return NULL;
}
/*
- * This function is called from do_exit or do_execv when task tk's stack is
- * about to be recycled. Recycle any function-return probe instances
- * associated with this task. These represent probed functions that have
- * been called but may never return.
+ * Keep all fields in the kprobe consistent
*/
-void kprobe_flush_task(struct task_struct *tk)
+static inline void copy_kprobe(struct kprobe *old_p, struct kprobe *p)
{
- unsigned long flags = 0;
- spin_lock_irqsave(&kprobe_lock, flags);
- arch_kprobe_flush_task(tk);
- spin_unlock_irqrestore(&kprobe_lock, flags);
+ memcpy(&p->opcode, &old_p->opcode, sizeof(kprobe_opcode_t));
+ memcpy(&p->ainsn, &old_p->ainsn, sizeof(struct arch_specific_insn));
}
/*
- * This kprobe pre_handler is registered with every kretprobe. When probe
- * hits it will set up the return probe.
- */
-static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs)
+* Add the new probe to old_p->list. Fail if this is the
+* second jprobe at the address - two jprobes can't coexist
+*/
+static int __kprobes add_new_kprobe(struct kprobe *old_p, struct kprobe *p)
{
- struct kretprobe *rp = container_of(p, struct kretprobe, kp);
+ struct kprobe *kp;
- /*TODO: consider to only swap the RA after the last pre_handler fired */
- arch_prepare_kretprobe(rp, regs);
+ if (p->break_handler) {
+ list_for_each_entry_rcu(kp, &old_p->list, list) {
+ if (kp->break_handler)
+ return -EEXIST;
+ }
+ list_add_tail_rcu(&p->list, &old_p->list);
+ } else
+ list_add_rcu(&p->list, &old_p->list);
return 0;
}
-static inline void free_rp_inst(struct kretprobe *rp)
-{
- struct kretprobe_instance *ri;
- while ((ri = get_free_rp_inst(rp)) != NULL) {
- hlist_del(&ri->uflist);
- kfree(ri);
- }
-}
-
/*
* Fill in the required fields of the "manager kprobe". Replace the
* earlier kprobe in the hlist with the manager kprobe
*/
static inline void add_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
{
+ copy_kprobe(p, ap);
ap->addr = p->addr;
- memcpy(&ap->opcode, &p->opcode, sizeof(kprobe_opcode_t));
- memcpy(&ap->ainsn, &p->ainsn, sizeof(struct arch_specific_insn));
-
ap->pre_handler = aggr_pre_handler;
ap->post_handler = aggr_post_handler;
ap->fault_handler = aggr_fault_handler;
+ ap->break_handler = aggr_break_handler;
INIT_LIST_HEAD(&ap->list);
- list_add(&p->list, &ap->list);
+ list_add_rcu(&p->list, &ap->list);
- INIT_HLIST_NODE(&ap->hlist);
- hlist_del(&p->hlist);
- hlist_add_head(&ap->hlist,
- &kprobe_table[hash_ptr(ap->addr, KPROBE_HASH_BITS)]);
+ hlist_replace_rcu(&p->hlist, &ap->hlist);
}
/*
* This is the second or subsequent kprobe at the address - handle
* the intricacies
- * TODO: Move kcalloc outside the spinlock
*/
-static int register_aggr_kprobe(struct kprobe *old_p, struct kprobe *p)
+static int __kprobes register_aggr_kprobe(struct kprobe *old_p,
+ struct kprobe *p)
{
int ret = 0;
struct kprobe *ap;
- if (old_p->break_handler || p->break_handler) {
- ret = -EEXIST; /* kprobe and jprobe can't (yet) coexist */
- } else if (old_p->pre_handler == aggr_pre_handler) {
- list_add(&p->list, &old_p->list);
+ if (old_p->pre_handler == aggr_pre_handler) {
+ 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);
- list_add(&p->list, &ap->list);
+ copy_kprobe(ap, p);
+ ret = add_new_kprobe(ap, 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(&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)
+static int __kprobes in_kprobes_functions(unsigned long addr)
{
- list_del(&p->list);
- if (list_empty(&old_p->list)) {
- cleanup_kprobe(old_p, flags);
- kfree(old_p);
- } else
- spin_unlock_irqrestore(&kprobe_lock, flags);
+ if (addr >= (unsigned long)__kprobes_text_start
+ && addr < (unsigned long)__kprobes_text_end)
+ return -EINVAL;
+ return 0;
}
-int register_kprobe(struct kprobe *p)
+static int __kprobes __register_kprobe(struct kprobe *p,
+ unsigned long called_from)
{
int ret = 0;
- unsigned long flags = 0;
struct kprobe *old_p;
-
- if ((ret = arch_prepare_kprobe(p)) != 0) {
- goto rm_kprobe;
+ struct module *probed_mod;
+
+ if ((!kernel_text_address((unsigned long) p->addr)) ||
+ in_kprobes_functions((unsigned long) p->addr))
+ return -EINVAL;
+
+ p->mod_refcounted = 0;
+ /* Check are we probing a module */
+ if ((probed_mod = module_text_address((unsigned long) p->addr))) {
+ struct module *calling_mod = module_text_address(called_from);
+ /* We must allow modules to probe themself and
+ * in this case avoid incrementing the module refcount,
+ * so as to allow unloading of self probing modules.
+ */
+ if (calling_mod && (calling_mod != probed_mod)) {
+ if (unlikely(!try_module_get(probed_mod)))
+ return -EINVAL;
+ p->mod_refcounted = 1;
+ } else
+ probed_mod = NULL;
}
- spin_lock_irqsave(&kprobe_lock, flags);
+
+ p->nmissed = 0;
+ mutex_lock(&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(&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);
+ mutex_unlock(&kprobe_mutex);
+
+ if (ret && probed_mod)
+ module_put(probed_mod);
return ret;
}
-void unregister_kprobe(struct kprobe *p)
+int __kprobes register_kprobe(struct kprobe *p)
{
- unsigned long flags;
- struct kprobe *old_p;
+ return __register_kprobe(p,
+ (unsigned long)__builtin_return_address(0));
+}
+
+void __kprobes unregister_kprobe(struct kprobe *p)
+{
+ struct module *mod;
+ struct kprobe *old_p, *list_p;
+ int cleanup_p;
- spin_lock_irqsave(&kprobe_lock, flags);
+ mutex_lock(&kprobe_mutex);
old_p = get_kprobe(p->addr);
- if (old_p) {
- if (old_p->pre_handler == aggr_pre_handler)
- cleanup_aggr_kprobe(old_p, p, flags);
- else
- cleanup_kprobe(p, flags);
- } else
- spin_unlock_irqrestore(&kprobe_lock, flags);
+ if (unlikely(!old_p)) {
+ mutex_unlock(&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;
+ mutex_unlock(&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;
+ }
+
+ mutex_unlock(&kprobe_mutex);
+
+ synchronize_sched();
+ if (p->mod_refcounted &&
+ (mod = module_text_address((unsigned long)p->addr)))
+ module_put(mod);
+
+ if (cleanup_p) {
+ if (p != old_p) {
+ list_del_rcu(&p->list);
+ kfree(old_p);
+ }
+ arch_remove_kprobe(p);
+ }
}
static struct notifier_block kprobe_exceptions_nb = {
.priority = 0x7fffffff /* we need to notified first */
};
-int register_jprobe(struct jprobe *jp)
+int __kprobes register_jprobe(struct jprobe *jp)
{
/* Todo: Verify probepoint is a function entry point */
jp->kp.pre_handler = setjmp_pre_handler;
jp->kp.break_handler = longjmp_break_handler;
- return register_kprobe(&jp->kp);
+ return __register_kprobe(&jp->kp,
+ (unsigned long)__builtin_return_address(0));
}
-void unregister_jprobe(struct jprobe *jp)
+void __kprobes unregister_jprobe(struct jprobe *jp)
{
unregister_kprobe(&jp->kp);
}
#ifdef ARCH_SUPPORTS_KRETPROBES
-int register_kretprobe(struct kretprobe *rp)
+/*
+ * This kprobe pre_handler is registered with every kretprobe. When probe
+ * hits it will set up the return probe.
+ */
+static int __kprobes pre_handler_kretprobe(struct kprobe *p,
+ struct pt_regs *regs)
+{
+ struct kretprobe *rp = container_of(p, struct kretprobe, kp);
+ unsigned long flags = 0;
+
+ /*TODO: consider to only swap the RA after the last pre_handler fired */
+ spin_lock_irqsave(&kretprobe_lock, flags);
+ arch_prepare_kretprobe(rp, regs);
+ spin_unlock_irqrestore(&kretprobe_lock, flags);
+ return 0;
+}
+
+int __kprobes register_kretprobe(struct kretprobe *rp)
{
int ret = 0;
struct kretprobe_instance *inst;
rp->nmissed = 0;
/* Establish function entry probe point */
- if ((ret = register_kprobe(&rp->kp)) != 0)
+ if ((ret = __register_kprobe(&rp->kp,
+ (unsigned long)__builtin_return_address(0))) != 0)
free_rp_inst(rp);
return ret;
}
#else /* ARCH_SUPPORTS_KRETPROBES */
-int register_kretprobe(struct kretprobe *rp)
+int __kprobes register_kretprobe(struct kretprobe *rp)
{
return -ENOSYS;
}
#endif /* ARCH_SUPPORTS_KRETPROBES */
-void unregister_kretprobe(struct kretprobe *rp)
+void __kprobes unregister_kretprobe(struct kretprobe *rp)
{
unsigned long flags;
struct kretprobe_instance *ri;
unregister_kprobe(&rp->kp);
/* No race here */
- spin_lock_irqsave(&kprobe_lock, flags);
- free_rp_inst(rp);
+ spin_lock_irqsave(&kretprobe_lock, flags);
while ((ri = get_used_rp_inst(rp)) != NULL) {
ri->rp = NULL;
hlist_del(&ri->uflist);
}
- spin_unlock_irqrestore(&kprobe_lock, flags);
+ spin_unlock_irqrestore(&kretprobe_lock, flags);
+ free_rp_inst(rp);
}
static int __init init_kprobes(void)
INIT_HLIST_HEAD(&kretprobe_inst_table[i]);
}
- err = register_die_notifier(&kprobe_exceptions_nb);
- /* Register the trampoline probe for return probe */
- register_kprobe(&trampoline_p);
+ err = arch_init_kprobes();
+ if (!err)
+ err = register_die_notifier(&kprobe_exceptions_nb);
+
return err;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff