[FIX] double call swap_unregister_kretprobe()

Change-Id: Ie785baec540d7226fa6969e89c0cb16511a7dd61
Signed-off-by: Vyacheslav Cherkashin <v.cherkashin@samsung.com>

diff --git a/loader/loader_module.c b/loader/loader_module.c
index c5ab6b2..d305b96 100644 (file)
--- a/loader/loader_module.c
+++ b/loader/loader_module.c
@@ -403,18 +403,30 @@ static struct kretprobe mmap_rp = {
        .handler = mmap_ret_handler
 };
 
+static bool mmap_rp_inst = false;
+static DEFINE_MUTEX(mmap_rp_mtx);
+
 static void loader_start_cb(void)
 {
        int res;
 
+       mutex_lock(&mmap_rp_mtx);
        res = swap_register_kretprobe(&mmap_rp);
        if (res != 0)
                printk(KERN_ERR LOADER_PREFIX "Registering do_mmap_pgoff probe failed\n");
+       else
+               mmap_rp_inst = true;
+       mutex_unlock(&mmap_rp_mtx);
 }
 
 static void loader_stop_cb(void)
 {
-       swap_unregister_kretprobe(&mmap_rp);
+       mutex_lock(&mmap_rp_mtx);
+       if (mmap_rp_inst) {
+               swap_unregister_kretprobe(&mmap_rp);
+               mmap_rp_inst = false;
+       }
+       mutex_unlock(&mmap_rp_mtx);
 }
 
 static unsigned long __not_loaded_entry(struct uretprobe_instance *ri,
@@ -553,7 +565,13 @@ int loader_set(void)
 
 void loader_unset(void)
 {
-       swap_unregister_kretprobe(&mmap_rp);
+       mutex_lock(&mmap_rp_mtx);
+       if (mmap_rp_inst) {
+               swap_unregister_kretprobe(&mmap_rp);
+               mmap_rp_inst = false;
+       }
+       mutex_unlock(&mmap_rp_mtx);
+
        /*module_put(THIS_MODULE);*/
        loader_module_set_not_ready();
 }