On 22/06/2017 14:43, Johannes Thumshirn wrote:
In qla2xx_start_scsi_mq() and qla2xx_dif_start_scsi_mq() we grab the
qpair->qp_lock but do access members of the qpair before having the lock.
Re-order the locking sequence to have all read and write access to qpair
members under the qpair->qp_lock.
Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
drivers/scsi/qla2xxx/qla_iocb.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/qla2xxx/qla_iocb.c b/drivers/scsi/qla2xxx/qla_iocb.c
index 8404f17f3c6c..425ca1646a9a 100644
--- a/drivers/scsi/qla2xxx/qla_iocb.c
+++ b/drivers/scsi/qla2xxx/qla_iocb.c
@@ -1770,10 +1770,6 @@ qla2xxx_start_scsi_mq(srb_t *sp)
struct qla_hw_data *ha = vha->hw;
struct qla_qpair *qpair = sp->qpair;
- /* Setup qpair pointers */
- rsp = qpair->rsp;
- req = qpair->req;
Can you check the call to qla2x00_marker() before the spinlock grab,
which takes rsp and req as parameters?
-
/* So we know we haven't pci_map'ed anything yet */
tot_dsds = 0;
@@ -1788,6 +1784,10 @@ qla2xxx_start_scsi_mq(srb_t *sp)
/* Acquire qpair specific lock */
spin_lock_irqsave(&qpair->qp_lock, flags);
+ /* Setup qpair pointers */
+ rsp = qpair->rsp;
+ req = qpair->req;
+
/* Check for room in outstanding command list. */
handle = req->current_outstanding_cmd;
for (index = 1; index < req->num_outstanding_cmds; index++) {
@@ -1924,24 +1924,33 @@ qla2xxx_dif_start_scsi_mq(srb_t *sp)
#define QDSS_GOT_Q_SPACE BIT_0
+ /* Acquire ring specific lock */
+ spin_lock_irqsave(&qpair->qp_lock, flags);
+
/* Check for host side state */
if (!qpair->online) {
cmd->result = DID_NO_CONNECT << 16;
+ spin_unlock_irqrestore(&qpair->qp_lock, flags);
return QLA_INTERFACE_ERROR;
}
if (!qpair->difdix_supported &&
scsi_get_prot_op(cmd) != SCSI_PROT_NORMAL) {
cmd->result = DID_NO_CONNECT << 16;
+ spin_unlock_irqrestore(&qpair->qp_lock, flags);
return QLA_INTERFACE_ERROR;
}
+ spin_unlock_irqrestore(&qpair->qp_lock, flags);
+
/* Only process protection or >16 cdb in this routine */
if (scsi_get_prot_op(cmd) == SCSI_PROT_NORMAL) {
if (cmd->cmd_len <= 16)
return qla2xxx_start_scsi_mq(sp);
}
+ spin_lock_irqsave(&qpair->qp_lock, flags);
+
/* Setup qpair pointers */
rsp = qpair->rsp;
req = qpair->req;
@@ -1957,9 +1966,6 @@ qla2xxx_dif_start_scsi_mq(srb_t *sp)
vha->marker_needed = 0;
}
- /* Acquire ring specific lock */
- spin_lock_irqsave(&qpair->qp_lock, flags);
-
/* Check for room in outstanding command list. */
handle = req->current_outstanding_cmd;
for (index = 1; index < req->num_outstanding_cmds; index++) {
