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 14:13:09 +0000 (16:13 +0200)
commit24678510078c388e89a14545790f28c62c010914
tree80f761a4a52b7a7fea1da83f7fd86a05ad0140ce
parenta3adc584abfb4ca44715a5c38d9fe88d9f16f1e5
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