From: Sagi Grimberg sagi@grimberg.me
[ Upstream commit 2875b0aecabe2f081a8432e2bc85b85df0529490 ]
commit fe35ec58f0d3 ("block: update hctx map when use multiple maps") exposed an issue where we may hang trying to wait for queue freeze during I/O. We call blk_mq_update_nr_hw_queues which in case of multiple queue maps (which we have now for default/read/poll) is attempting to freeze the queue. However we never started queue freeze when starting the reset, which means that we have inflight pending requests that entered the queue that we will not complete once the queue is quiesced.
So start a freeze before we quiesce the queue, and unfreeze the queue after we successfully connected the I/O queues (and make sure to call blk_mq_update_nr_hw_queues only after we are sure that the queue was already frozen).
This follows to how the pci driver handles resets.
Fixes: fe35ec58f0d3 ("block: update hctx map when use multiple maps") Signed-off-by: Sagi Grimberg sagi@grimberg.me Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/nvme/host/tcp.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 53e113a18a549..0166ff0e4738e 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1684,15 +1684,20 @@ static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new) ret = PTR_ERR(ctrl->connect_q); goto out_free_tag_set; } - } else { - blk_mq_update_nr_hw_queues(ctrl->tagset, - ctrl->queue_count - 1); }
ret = nvme_tcp_start_io_queues(ctrl); if (ret) goto out_cleanup_connect_q;
+ if (!new) { + nvme_start_queues(ctrl); + nvme_wait_freeze(ctrl); + blk_mq_update_nr_hw_queues(ctrl->tagset, + ctrl->queue_count - 1); + nvme_unfreeze(ctrl); + } + return 0;
out_cleanup_connect_q: @@ -1797,6 +1802,7 @@ static void nvme_tcp_teardown_io_queues(struct nvme_ctrl *ctrl, { if (ctrl->queue_count <= 1) return; + nvme_start_freeze(ctrl); nvme_stop_queues(ctrl); nvme_tcp_stop_io_queues(ctrl); if (ctrl->tagset) {