linux/drivers/nvme
Sagi Grimberg ca3b4293dc nvmet: fix ns enable/disable possible hang
[ Upstream commit f97914e35f ]

When disabling an nvmet namespace, there is a period where the
subsys->lock is released, as the ns disable waits for backend IO to
complete, and the ns percpu ref to be properly killed. The original
intent was to avoid taking the subsystem lock for a prolong period as
other processes may need to acquire it (for example new incoming
connections).

However, it opens up a window where another process may come in and
enable the ns, (re)intiailizing the ns percpu_ref, causing the disable
sequence to hang.

Solve this by taking the global nvmet_config_sem over the entire configfs
enable/disable sequence.

Fixes: a07b4970f4 ("nvmet: add a generic NVMe target")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-06-12 11:12:53 +02:00
..
common treewide: use get_random_u32() when possible 2022-10-11 17:42:58 -06:00
host nvme-multipath: fix io accounting on failover 2024-06-12 11:12:53 +02:00
target nvmet: fix ns enable/disable possible hang 2024-06-12 11:12:53 +02:00
Kconfig nvme: implement In-Band authentication 2022-08-02 17:14:49 -06:00
Makefile nvme: implement In-Band authentication 2022-08-02 17:14:49 -06:00