2 files changed, 20 insertions, 2 deletions

diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index 077f65321b5e..925eaf28fca9 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -268,6 +268,8 @@ extern void kprobes_inc_nmissed_count(struct kprobe *p);
 
 struct kprobe_insn_cache {
         struct mutex mutex;
+        void *(*alloc)(void);   /* allocate insn page */
+        void (*free)(void *);   /* free insn page */
         struct list_head pages; /* list of kprobe_insn_page */
         size_t insn_size;       /* size of instruction slot */
         int nr_garbage;
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 9e4912dc5559..a0d367a49122 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -112,6 +112,7 @@ static struct kprobe_blackpoint kprobe_blacklist[] = {
 struct kprobe_insn_page {
         struct list_head list;
         kprobe_opcode_t *insns;         /* Page of instruction slots */
+        struct kprobe_insn_cache *cache;
         int nused;
         int ngarbage;
         char slot_used[];
@@ -132,8 +133,20 @@ enum kprobe_slot_state {
         SLOT_USED = 2,
 };
 
+static void *alloc_insn_page(void)
+{
+        return module_alloc(PAGE_SIZE);
+}
+
+static void free_insn_page(void *page)
+{
+        module_free(NULL, page);
+}
+
 struct kprobe_insn_cache kprobe_insn_slots = {
         .mutex = __MUTEX_INITIALIZER(kprobe_insn_slots.mutex),
+        .alloc = alloc_insn_page,
+        .free = free_insn_page,
         .pages = LIST_HEAD_INIT(kprobe_insn_slots.pages),
         .insn_size = MAX_INSN_SIZE,
         .nr_garbage = 0,
@@ -182,7 +195,7 @@ kprobe_opcode_t __kprobes *__get_insn_slot(struct kprobe_insn_cache *c)
          * 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);
+        kip->insns = c->alloc();
         if (!kip->insns) {
                 kfree(kip);
                 goto out;
@@ -192,6 +205,7 @@ kprobe_opcode_t __kprobes *__get_insn_slot(struct kprobe_insn_cache *c)
         kip->slot_used[0] = SLOT_USED;
         kip->nused = 1;
         kip->ngarbage = 0;
+        kip->cache = c;
         list_add(&kip->list, &c->pages);
         slot = kip->insns;
 out:
@@ -213,7 +227,7 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx)
                  */
                 if (!list_is_singular(&kip->list)) {
                         list_del(&kip->list);
-                        module_free(NULL, kip->insns);
+                        kip->cache->free(kip->insns);
                         kfree(kip);
                 }
                 return 1;
@@ -274,6 +288,8 @@ out:
 /* For optimized_kprobe buffer */
 struct kprobe_insn_cache kprobe_optinsn_slots = {
         .mutex = __MUTEX_INITIALIZER(kprobe_optinsn_slots.mutex),
+        .alloc = alloc_insn_page,
+        .free = free_insn_page,
         .pages = LIST_HEAD_INIT(kprobe_optinsn_slots.pages),
         /* .insn_size is initialized later */
         .nr_garbage = 0,