1 files changed, 26 insertions, 2 deletions

diff --git a/kernel/module.c b/kernel/module.c
index 63cf6e7f1394..74bc19562ca3 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2845,6 +2845,20 @@ static int post_relocation(struct module *mod, const struct load_info *info)
         return module_finalize(info->hdr, info->sechdrs, mod);
 }
 
+/* Is this module of this name done loading?  No locks held. */
+static bool finished_loading(const char *name)
+{
+        struct module *mod;
+        bool ret;
+
+        mutex_lock(&module_mutex);
+        mod = find_module(name);
+        ret = !mod || mod->state != MODULE_STATE_COMING;
+        mutex_unlock(&module_mutex);
+
+        return ret;
+}
+
 /* Allocate and load the module: note that size of section 0 is always
    zero, and we rely on this for optional sections. */
 static struct module *load_module(void __user *umod,
@@ -2852,7 +2866,7 @@ static struct module *load_module(void __user *umod,
                                   const char __user *uargs)
 {
         struct load_info info = { NULL, };
-        struct module *mod;
+        struct module *mod, *old;
         long err;
 
         pr_debug("load_module: umod=%p, len=%lu, uargs=%p\n",
@@ -2918,8 +2932,18 @@ static struct module *load_module(void __user *umod,
          * function to insert in a way safe to concurrent readers.
          * The mutex protects against concurrent writers.
          */
+again:
         mutex_lock(&module_mutex);
-        if (find_module(mod->name)) {
+        if ((old = find_module(mod->name)) != NULL) {
+                if (old->state == MODULE_STATE_COMING) {
+                        /* Wait in case it fails to load. */
+                        mutex_unlock(&module_mutex);
+                        err = wait_event_interruptible(module_wq,
+                                               finished_loading(mod->name));
+                        if (err)
+                                goto free_arch_cleanup;
+                        goto again;
+                }
                 err = -EEXIST;
                 goto unlock;
         }