This is a note to let you know that I've just added the patch titled
nvme-tcp: fix potential unbalanced freeze & unfreeze
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nvme-tcp-fix-potential-unbalanced-freeze-unfreeze.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 99dc264014d5aed66ee37ddf136a38b5a2b1b529 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@xxxxxxxxxx>
Date: Tue, 11 Jul 2023 17:40:40 +0800
Subject: nvme-tcp: fix potential unbalanced freeze & unfreeze
From: Ming Lei <ming.lei@xxxxxxxxxx>
commit 99dc264014d5aed66ee37ddf136a38b5a2b1b529 upstream.
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@xxxxxxxxxxxxxxx
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Tested-by: Yi Zhang <yi.zhang@xxxxxxxxxx>
Reviewed-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/nvme/host/tcp.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -1888,6 +1888,7 @@ static int nvme_tcp_configure_io_queues(
goto out_cleanup_connect_q;
if (!new) {
+ nvme_start_freeze(ctrl);
nvme_start_queues(ctrl);
if (!nvme_wait_freeze_timeout(ctrl, NVME_IO_TIMEOUT)) {
/*
@@ -1896,6 +1897,7 @@ static int nvme_tcp_configure_io_queues(
* to be safe.
*/
ret = -ENODEV;
+ nvme_unfreeze(ctrl);
goto out_wait_freeze_timed_out;
}
blk_mq_update_nr_hw_queues(ctrl->tagset,
@@ -2014,7 +2016,6 @@ static void nvme_tcp_teardown_io_queues(
if (ctrl->queue_count <= 1)
return;
blk_mq_quiesce_queue(ctrl->admin_q);
- nvme_start_freeze(ctrl);
nvme_stop_queues(ctrl);
nvme_sync_io_queues(ctrl);
nvme_tcp_stop_io_queues(ctrl);
Patches currently in stable-queue which might be from ming.lei@xxxxxxxxxx are
queue-5.15/nvme-tcp-fix-potential-unbalanced-freeze-unfreeze.patch
queue-5.15/nvme-rdma-fix-potential-unbalanced-freeze-unfreeze.patch
