iscsi-target: Fix iser explicit logout TX kthread leak
authorNicholas Bellinger <nab@linux-iscsi.org>
Thu, 23 Jul 2015 22:30:31 +0000 (22:30 +0000)
committerNicholas Bellinger <nab@linux-iscsi.org>
Fri, 24 Jul 2015 21:19:44 +0000 (14:19 -0700)
commit007d038bdf95ccfe2491d0078be54040d110fd06
treea422ccc909a36f60ec4ff5dfbf976ae077c78e36
parente54198657b65625085834847ab6271087323ffea
iscsi-target: Fix iser explicit logout TX kthread leak

This patch fixes a regression introduced with the following commit
in v4.0-rc1 code, where an explicit iser-target logout would result
in ->tx_thread_active being incorrectly cleared by the logout post
handler, and subsequent TX kthread leak:

    commit 88dcd2dab5c23b1c9cfc396246d8f476c872f0ca
    Author: Nicholas Bellinger <nab@linux-iscsi.org>
    Date:   Thu Feb 26 22:19:15 2015 -0800

        iscsi-target: Convert iscsi_thread_set usage to kthread.h

To address this bug, change iscsit_logout_post_handler_closesession()
and iscsit_logout_post_handler_samecid() to only cmpxchg() on
->tx_thread_active for traditional iscsi/tcp connections.

This is required because iscsi/tcp connections are invoking logout
post handler logic directly from TX kthread context, while iser
connections are invoking logout post handler logic from a seperate
workqueue context.

Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
drivers/target/iscsi/iscsi_target.c