On Sat, May 20, 2017 at 11:56:04AM +0800, Ming Lei wrote: > NVMe may add request into requeue list simply and not kick off the > requeue if hw queues are stopped. Then blk_mq_abort_requeue_list() > is called in both nvme_kill_queues() and nvme_ns_remove() for > dealing with this issue. > > Unfortunately blk_mq_abort_requeue_list() is absolutely a > race maker, for example, one request may be requeued during > the aborting. So this patch just calls blk_mq_kick_requeue_list() in > nvme_kill_queues() to handle this issue like what nvme_start_queues() > does. Now all requests in requeue list when queues are stopped will be > handled by blk_mq_kick_requeue_list() when queues are restarted, either > in nvme_start_queues() or in nvme_kill_queues(). > > Cc: stable@xxxxxxxxxxxxxxx > Reported-by: Zhang Yi <yizhan@xxxxxxxxxx> > Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> > --- > drivers/nvme/host/core.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c > index ce0d96913ee6..9ce0a0a16984 100644 > --- a/drivers/nvme/host/core.c > +++ b/drivers/nvme/host/core.c > @@ -2098,7 +2098,6 @@ static void nvme_ns_remove(struct nvme_ns *ns) > if (ns->ndev) > nvme_nvm_unregister_sysfs(ns); > del_gendisk(ns->disk); > - blk_mq_abort_requeue_list(ns->queue); > blk_cleanup_queue(ns->queue); > } > > @@ -2436,7 +2435,6 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl) > continue; > revalidate_disk(ns->disk); > blk_set_queue_dying(ns->queue); > - blk_mq_abort_requeue_list(ns->queue); > > /* > * We have to force to start queues for avoiding hang > @@ -2444,6 +2442,9 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl) > * be stopped forever from now on. > */ > blk_mq_start_hw_queues(ns->queue); > + > + /* draining requests in requeue list */ > + blk_mq_kick_requeue_list(q); oops, the above line causes build failure, please take the following one. --- >From e70cfe2edacf278e3e6605f8c08e01ebf65bff01 Mon Sep 17 00:00:00 2001 From: Ming Lei <ming.lei@xxxxxxxxxx> Date: Wed, 17 May 2017 09:02:07 +0800 Subject: [PATCH v2 2/3] nvme: avoid to use blk_mq_abort_requeue_list() NVMe may add request into requeue list simply and not kick off the requeue if hw queues are stopped. Then blk_mq_abort_requeue_list() is called in both nvme_kill_queues() and nvme_ns_remove() for dealing with this issue. Unfortunately blk_mq_abort_requeue_list() is absolutely a race maker, for example, one request may be requeued during the aborting. So this patch just calls blk_mq_kick_requeue_list() in nvme_kill_queues() to handle this issue like what nvme_start_queues() does. Now all requests in requeue list when queues are stopped will be handled by blk_mq_kick_requeue_list() when queues are restarted, either in nvme_start_queues() or in nvme_kill_queues(). Cc: stable@xxxxxxxxxxxxxxx Reported-by: Zhang Yi <yizhan@xxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- drivers/nvme/host/core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index ce0d96913ee6..e344f5d7c1bc 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2098,7 +2098,6 @@ static void nvme_ns_remove(struct nvme_ns *ns) if (ns->ndev) nvme_nvm_unregister_sysfs(ns); del_gendisk(ns->disk); - blk_mq_abort_requeue_list(ns->queue); blk_cleanup_queue(ns->queue); } @@ -2436,7 +2435,6 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl) continue; revalidate_disk(ns->disk); blk_set_queue_dying(ns->queue); - blk_mq_abort_requeue_list(ns->queue); /* * We have to force to start queues for avoiding hang @@ -2444,6 +2442,9 @@ void nvme_kill_queues(struct nvme_ctrl *ctrl) * be stopped forever from now on. */ blk_mq_start_hw_queues(ns->queue); + + /* draining requests in requeue list */ + blk_mq_kick_requeue_list(ns->queue); } mutex_unlock(&ctrl->namespaces_mutex); } -- 2.9.4