Merge remote-tracking branch 'torvalds/master' into perf/core

To sync with libbpf, etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 21 insertions, 5 deletions

diff --git a/kernel/module/main.c b/kernel/module/main.c
index 48568a0f5651..4ac3fe43e6c8 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2393,7 +2393,8 @@ static bool finished_loading(const char *name)
 	sched_annotate_sleep();
 	mutex_lock(&module_mutex);
 	mod = find_module_all(name, strlen(name), true);
-	ret = !mod || mod->state == MODULE_STATE_LIVE;
+	ret = !mod || mod->state == MODULE_STATE_LIVE
+		|| mod->state == MODULE_STATE_GOING;
 	mutex_unlock(&module_mutex);
 
 	return ret;
@@ -2569,20 +2570,35 @@ static int add_unformed_module(struct module *mod)
 
 	mod->state = MODULE_STATE_UNFORMED;
 
-again:
 	mutex_lock(&module_mutex);
 	old = find_module_all(mod->name, strlen(mod->name), true);
 	if (old != NULL) {
-		if (old->state != MODULE_STATE_LIVE) {
+		if (old->state == MODULE_STATE_COMING
+		    || old->state == MODULE_STATE_UNFORMED) {
 			/* Wait in case it fails to load. */
 			mutex_unlock(&module_mutex);
 			err = wait_event_interruptible(module_wq,
 					       finished_loading(mod->name));
 			if (err)
 				goto out_unlocked;
-			goto again;
+
+			/* The module might have gone in the meantime. */
+			mutex_lock(&module_mutex);
+			old = find_module_all(mod->name, strlen(mod->name),
+					      true);
 		}
-		err = -EEXIST;
+
+		/*
+		 * We are here only when the same module was being loaded. Do
+		 * not try to load it again right now. It prevents long delays
+		 * caused by serialized module load failures. It might happen
+		 * when more devices of the same type trigger load of
+		 * a particular module.
+		 */
+		if (old && old->state == MODULE_STATE_LIVE)
+			err = -EEXIST;
+		else
+			err = -EBUSY;
 		goto out;
 	}
 	mod_update_bounds(mod);