block: elevator: forbid init from changing I/O scheduler

Userspace sets bfq when booting is done, we do not want this to happen because we use upstreamed cfq by default. Signed-off-by: Yaroslav Furman <[email protected]>
penglezos · Apr 6, 2019 · 3a54f49 · 3a54f49
1 parent fa80dae
commit 3a54f49
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/block/elevator.c b/block/elevator.c
@@ -83,6 +83,10 @@ static struct elevator_type *elevator_find(const char *name)
 {
 	struct elevator_type *e;
 
+	/* Forbid init from changing I/O scheduler from default */
+	if (!strncmp(current->comm, "init", sizeof("init")))
+		return NULL;
+
 	list_for_each_entry(e, &elv_list, list) {
 		if (!strcmp(e->elevator_name, name))
 			return e;