scsi: lpfc: Fix soft lockup in lpfc worker thread during LIP testing
authorJames Smart <jsmart2021@gmail.com>
Tue, 30 Jan 2018 23:58:54 +0000 (15:58 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 25 May 2018 14:17:51 +0000 (16:17 +0200)
commit8fd4131a9fcc0ad8a60554c0505804b258362552
tree2b6dbf763ec9febf2ff65af19ffd69d1f4a11c14
parentd5d331cdfcb27e6c5dd5c10ac0452f7442bbc6c5
scsi: lpfc: Fix soft lockup in lpfc worker thread during LIP testing

[ Upstream commit 161df4f09987ae2e9f0f97f0b38eee298b4a39ff ]

During link bounce testing in a point-to-point topology, the host may
enter a soft lockup on the lpfc_worker thread:

    Call Trace:
     lpfc_work_done+0x1f3/0x1390 [lpfc]
     lpfc_do_work+0x16f/0x180 [lpfc]
     kthread+0xc7/0xe0
     ret_from_fork+0x3f/0x70

The driver was simultaneously setting a combination of flags that caused
lpfc_do_work()to effectively spin between slow path work and new event
data, causing the lockup.

Ensure in the typical wq completions, that new event data flags are set
if the slow path flag is running. The slow path will eventually
reschedule the wq handling.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/scsi/lpfc/lpfc_hbadisc.c