Merge branch 'master' into for-3.9-async

[~andy/linux] / kernel / kmod.c

diff --git a/kernel/kmod.c b/kernel/kmod.c
index 1c317e386831869a3c4ff17a675a06b3b985c06d..56dd34976d7b0d0ba5526ec2ee00a97e8f1339aa 100644 (file)
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -38,6 +38,7 @@
 #include <linux/suspend.h>
 #include <linux/rwsem.h>
 #include <linux/ptrace.h>
+#include <linux/async.h>
 #include <asm/uaccess.h>
 
 #include <trace/events/module.h>
@@ -130,6 +131,14 @@ int __request_module(bool wait, const char *fmt, ...)
 #define MAX_KMOD_CONCURRENT 50 /* Completely arbitrary value - KAO */
        static int kmod_loop_msg;
 
+       /*
+        * We don't allow synchronous module loading from async.  Module
+        * init may invoke async_synchronize_full() which will end up
+        * waiting for this task which already is waiting for the module
+        * loading to complete, leading to a deadlock.
+        */
+       WARN_ON_ONCE(wait && current_is_async());
+
        va_start(args, fmt);
        ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
        va_end(args);
@@ -219,9 +228,9 @@ static int ____call_usermodehelper(void *data)
 
        commit_creds(new);
 
-       retval = kernel_execve(sub_info->path,
-                              (const char *const *)sub_info->argv,
-                              (const char *const *)sub_info->envp);
+       retval = do_execve(sub_info->path,
+                          (const char __user *const __user *)sub_info->argv,
+                          (const char __user *const __user *)sub_info->envp);
        if (!retval)
                return 0;