On Wed, 2017-10-18 at 09:39 -0700, Bart Van Assche wrote: > On Tue, 2017-10-17 at 09:55 +0800, chenxiang (M) wrote: > > I find there is a race between blk_cleanup_queue and blk_timeout_work > > Thanks for the detailed report. Would it be possible to test the patch below > (applies on top of https://github.com/bvanassche/linux/tree/blk-mq-pm-2017-10-18-v10)? Here is a better version of the patch included in the previous e-mail: Subject: [PATCH] block: Fix race between blk_cleanup_queue() and timeout handling Make sure that if the timeout timer fires after a queue has been marked "dying" that the affected requests are finished. --- block/blk-core.c | 2 ++ block/blk-timeout.c | 3 --- 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index 4fc9d6d44edd..0a0fdaa474e3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -333,6 +333,7 @@ EXPORT_SYMBOL(blk_stop_queue); void blk_sync_queue(struct request_queue *q) { del_timer_sync(&q->timeout); + cancel_work_sync(&q->timeout_work); if (q->mq_ops) { struct blk_mq_hw_ctx *hctx; @@ -905,6 +906,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) setup_timer(&q->backing_dev_info->laptop_mode_wb_timer, laptop_mode_timer_fn, (unsigned long) q); setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q); + INIT_WORK(&q->timeout_work, NULL); INIT_LIST_HEAD(&q->queue_head); INIT_LIST_HEAD(&q->timeout_list); INIT_LIST_HEAD(&q->icq_list); diff --git a/block/blk-timeout.c b/block/blk-timeout.c index 1eba71486716..764ecf9aeb30 100644 --- a/block/blk-timeout.c +++ b/block/blk-timeout.c @@ -134,8 +134,6 @@ void blk_timeout_work(struct work_struct *work) struct request *rq, *tmp; int next_set = 0; - if (blk_queue_enter(q, BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_PREEMPT)) - return; spin_lock_irqsave(q->queue_lock, flags); list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list) @@ -145,7 +143,6 @@ void blk_timeout_work(struct work_struct *work) mod_timer(&q->timeout, round_jiffies_up(next)); spin_unlock_irqrestore(q->queue_lock, flags); - blk_queue_exit(q); } /** -- 2.14.2
