[PATCH 4.15 136/146] scsi: qla2xxx: Fix abort command deadlock due to spinlock

From: Greg Kroah-Hartman
Date: Tue Mar 13 2018 - 12:26:22 EST


4.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Quinn Tran <quinn.tran@xxxxxxxxxx>

commit b0dcce746b32ac573343ad39cb3dc485030de95e upstream.

Original code acquires hardware_lock to add Abort IOCB onto driver
request queue for processing. However, abort_command() will also acquire
hardware lock to look up sp pointer before issuing abort IOCB command
resulting into a deadlock. This patch safely removes the possible
deadlock scenario by removing extra spinlock.

Fixes: 6eb54715b54bb ("qla2xxx: Added interface to send explicit LOGO.")
Cc: <stable@xxxxxxxxxxxxxxx> # 4.10+
Signed-off-by: Quinn Tran <quinn.tran@xxxxxxxxxx>
Signed-off-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/scsi/qla2xxx/qla_iocb.c | 3 ---
1 file changed, 3 deletions(-)

--- a/drivers/scsi/qla2xxx/qla_iocb.c
+++ b/drivers/scsi/qla2xxx/qla_iocb.c
@@ -2394,7 +2394,6 @@ qla2x00_els_dcmd_iocb_timeout(void *data
struct scsi_qla_host *vha = sp->vha;
struct qla_hw_data *ha = vha->hw;
struct srb_iocb *lio = &sp->u.iocb_cmd;
- unsigned long flags = 0;

ql_dbg(ql_dbg_io, vha, 0x3069,
"%s Timeout, hdl=%x, portid=%02x%02x%02x\n",
@@ -2402,7 +2401,6 @@ qla2x00_els_dcmd_iocb_timeout(void *data
fcport->d_id.b.al_pa);

/* Abort the exchange */
- spin_lock_irqsave(&ha->hardware_lock, flags);
if (ha->isp_ops->abort_command(sp)) {
ql_dbg(ql_dbg_io, vha, 0x3070,
"mbx abort_command failed.\n");
@@ -2410,7 +2408,6 @@ qla2x00_els_dcmd_iocb_timeout(void *data
ql_dbg(ql_dbg_io, vha, 0x3071,
"mbx abort_command success.\n");
}
- spin_unlock_irqrestore(&ha->hardware_lock, flags);

complete(&lio->u.els_logo.comp);
}