diff options
-rw-r--r-- | block/ll_rw_blk.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 6b5173ac8131..c99b46354859 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -340,6 +340,15 @@ unsigned blk_ordered_req_seq(struct request *rq) if (rq == &q->post_flush_rq) return QUEUE_ORDSEQ_POSTFLUSH; + /* + * !fs requests don't need to follow barrier ordering. Always + * put them at the front. This fixes the following deadlock. + * + * http://thread.gmane.org/gmane.linux.kernel/537473 + */ + if (!blk_fs_request(rq)) + return QUEUE_ORDSEQ_DRAIN; + if ((rq->cmd_flags & REQ_ORDERED_COLOR) == (q->orig_bar_rq->cmd_flags & REQ_ORDERED_COLOR)) return QUEUE_ORDSEQ_DRAIN; |