FAILED: patch "[PATCH] nvme-tcp: fix potential unbalanced freeze & unfreeze" failed to apply to 5.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y
git checkout FETCH_HEAD
git cherry-pick -x 99dc264014d5aed66ee37ddf136a38b5a2b1b529
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2023081229-semicolon-uplifting-ffd6@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

99dc264014d5 ("nvme-tcp: fix potential unbalanced freeze & unfreeze")
9f27bd701d18 ("nvme: rename the queue quiescing helpers")
91c11d5f3254 ("nvme-rdma: stop auth work after tearing down queues in error recovery")
1f1a4f89562d ("nvme-tcp: stop auth work after tearing down queues in error recovery")
eac3ef262941 ("nvme-pci: split the initial probe from the rest path")
a6ee7f19ebfd ("nvme-pci: call nvme_pci_configure_admin_queue from nvme_pci_enable")
3f30a79c2e2c ("nvme-pci: set constant paramters in nvme_pci_alloc_ctrl")
2e87570be9d2 ("nvme-pci: factor out a nvme_pci_alloc_dev helper")
081a7d958ce4 ("nvme-pci: factor the iod mempool creation into a helper")
94cc781f69f4 ("nvme: move OPAL setup from PCIe to core")
cd50f9b24726 ("nvme: split nvme_kill_queues")
6bcd5089ee13 ("nvme: don't unquiesce the admin queue in nvme_kill_queues")
0ffc7e98bfaa ("nvme-pci: refactor the tagset handling in nvme_reset_work")
71b26083d59c ("block: set the disk capacity to 0 in blk_mark_disk_dead")
6dfba1c09c10 ("nvme-fc: use the tagset alloc/free helpers")
1864ea46155c ("nvme-fc: store the generic nvme_ctrl in set->driver_data")
cefa1032f111 ("nvme-rdma: use the tagset alloc/free helpers")
2d60738c8f80 ("nvme-rdma: store the generic nvme_ctrl in set->driver_data")
fe60e8c53411 ("nvme: add common helpers to allocate and free tagsets")
61ce339f19fa ("nvme-pci: set min_align_mask before calculating max_hw_sectors")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 99dc264014d5aed66ee37ddf136a38b5a2b1b529 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@redhat.com>
Date: Tue, 11 Jul 2023 17:40:40 +0800
Subject: [PATCH] nvme-tcp: fix potential unbalanced freeze & unfreeze

Move start_freeze into nvme_tcp_configure_io_queues(), and there is
at least two benefits:

1) fix unbalanced freeze and unfreeze, since re-connection work may
fail or be broken by removal

2) IO during error recovery can be failfast quickly because nvme fabrics
unquiesces queues after teardown.

One side-effect is that !mpath request may timeout during connecting
because of queue topo change, but that looks not one big deal:

1) same problem exists with current code base

2) compared with !mpath, mpath use case is dominant

Fixes: 2875b0aecabe ("nvme-tcp: fix controller reset hang during traffic")
Cc: stable@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 3e7dd6f91832..fb24cd8ac46c 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1868,6 +1868,7 @@ static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new)
 		goto out_cleanup_connect_q;
 
 	if (!new) {
+		nvme_start_freeze(ctrl);
 		nvme_unquiesce_io_queues(ctrl);
 		if (!nvme_wait_freeze_timeout(ctrl, NVME_IO_TIMEOUT)) {
 			/*
@@ -1876,6 +1877,7 @@ static int nvme_tcp_configure_io_queues(struct nvme_ctrl *ctrl, bool new)
 			 * to be safe.
 			 */
 			ret = -ENODEV;
+			nvme_unfreeze(ctrl);
 			goto out_wait_freeze_timed_out;
 		}
 		blk_mq_update_nr_hw_queues(ctrl->tagset,
@@ -1980,7 +1982,6 @@ static void nvme_tcp_teardown_io_queues(struct nvme_ctrl *ctrl,
 	if (ctrl->queue_count <= 1)
 		return;
 	nvme_quiesce_admin_queue(ctrl);
-	nvme_start_freeze(ctrl);
 	nvme_quiesce_io_queues(ctrl);
 	nvme_sync_io_queues(ctrl);
 	nvme_tcp_stop_io_queues(ctrl);