We would never be able to sort the list if we first reset plug->rq_count which is used in conditional check later. Fixes: ce5b009cff19 ("block: improve logic around when to sort a plug list") Signed-off-by: Dongli Zhang <dongli.zhang@xxxxxxxxxx> --- block/blk-mq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 3ff3d7b..c162718 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1711,11 +1711,12 @@ void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule) unsigned int depth; list_splice_init(&plug->mq_list, &list); - plug->rq_count = 0; if (plug->rq_count > 2 && plug->multiple_queues) list_sort(NULL, &list, plug_rq_cmp); + plug->rq_count = 0; + this_q = NULL; this_hctx = NULL; this_ctx = NULL; -- 2.7.4