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)
committerMartin K. Petersen <martin.petersen@oracle.com>
Mon, 12 Feb 2018 16:43:23 +0000 (11:43 -0500)
commit161df4f09987ae2e9f0f97f0b38eee298b4a39ff
tree71414577d49a2cd1e9538abe4e2fef56f86165e5
parent64bf009933bc84a7fb44ff50f86af0201b8be0c3
scsi: lpfc: Fix soft lockup in lpfc worker thread during LIP testing

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>
drivers/scsi/lpfc/lpfc_hbadisc.c