diff options
| -rw-r--r-- | block/blk-core.c | 10 | ||||
| -rw-r--r-- | block/elevator.c | 6 |
2 files changed, 15 insertions, 1 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 0c611d89d748..fce4b9387f36 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -741,9 +741,17 @@ blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, q->sg_reserved_size = INT_MAX; + /* Protect q->elevator from elevator_change */ + mutex_lock(&q->sysfs_lock); + /* init elevator */ - if (elevator_init(q, NULL)) + if (elevator_init(q, NULL)) { + mutex_unlock(&q->sysfs_lock); return NULL; + } + + mutex_unlock(&q->sysfs_lock); + return q; } EXPORT_SYMBOL(blk_init_allocated_queue); diff --git a/block/elevator.c b/block/elevator.c index 2bcbd8cc14d4..249cc5e10906 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -186,6 +186,12 @@ int elevator_init(struct request_queue *q, char *name) struct elevator_type *e = NULL; int err; + /* + * q->sysfs_lock must be held to provide mutual exclusion between + * elevator_switch() and here. + */ + lockdep_assert_held(&q->sysfs_lock); + if (unlikely(q->elevator)) return 0; |