[PATCH] set mod->waiter before calling stop_machine

From: Rusty Russell <rusty@rustcorp.com.au>

mod->waiter needs to be set before we try to stop the module: setting it in
__try_stop_module means it gets set to the kthread, not rmmod.

kernel/module.c

@@ -493,7 +493,6 @@ static inline int __try_stop_module(void *_sref)
 	}
 
 	/* Mark it as dying. */
-	sref->mod->waiter = current;
 	sref->mod->state = MODULE_STATE_GOING;
 	return 0;
 }
@@ -588,6 +587,9 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
 		}
 	}
 
+	/* Set this up before setting mod->state */
+	mod->waiter = current;
+
 	/* Stop the machine so refcounts can't move and disable module. */
 	ret = try_stop_module(mod, flags, &forced);