[PATCH AUTOSEL 6.17-5.15] nvmet-fc: avoid scheduling association deletion twice

[Daniel Wagner]

Hi Sasha,

On Thu, Oct 09, 2025 at 11:54:41AM -0400, Sasha Levin wrote:
> From: Daniel Wagner <wagi at kernel.org>
> 
> [ Upstream commit f2537be4f8421f6495edfa0bc284d722f253841d ]
> 
> When forcefully shutting down a port via the configfs interface,
> nvmet_port_subsys_drop_link() first calls nvmet_port_del_ctrls() and
> then nvmet_disable_port(). Both functions will eventually schedule all
> remaining associations for deletion.
> 
> The current implementation checks whether an association is about to be
> removed, but only after the work item has already been scheduled. As a
> result, it is possible for the first scheduled work item to free all
> resources, and then for the same work item to be scheduled again for
> deletion.
> 
> Because the association list is an RCU list, it is not possible to take
> a lock and remove the list entry directly, so it cannot be looked up
> again. Instead, a flag (terminating) must be used to determine whether
> the association is already in the process of being deleted.
> 
> Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki at wdc.com>
> Closes: https://lore.kernel.org/all/rsdinhafrtlguauhesmrrzkybpnvwantwmyfq2ih5aregghax5@mhr7v3eryci3/
> Reviewed-by: Hannes Reinecke <hare at suse.de>
> Signed-off-by: Daniel Wagner <wagi at kernel.org>
> Signed-off-by: Keith Busch <kbusch at kernel.org>
> Signed-off-by: Sasha Levin <sashal at kernel.org>

This patch is part of a whole series:

https://lore.kernel.org/all/20250902-fix-nvmet-fc-v3-0-1ae1ecb798d8@kernel.org/

IMO, all should all be backported:

db5a5406fb7e nvmet-fc: move lsop put work to nvmet_fc_ls_req_op
f2537be4f842 nvmet-fc: avoid scheduling association deletion twice
10c165af35d2 nvmet-fcloop: call done callback even when remote port is gone
891cdbb162cc nvme-fc: use lock accessing port_state and rport state

Thanks,
Daniel