scsi: libiscsi: Fix locking in __iscsi_conn_send_pdu

The code at free_task label in __iscsi_conn_send_pdu can get executed
from blk_timeout_work which takes queue_lock using spin_lock_irq.
back_lock taken with spin_unlock_bh will cause WARN_ON_ONCE.  The code
gets executed either with bottom half or IRQ disabled hence using
spin_lock/spin_unlock for back_lock is safe.

Signed-off-by: Jitendra Bhivare <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Chris Leech <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>
This commit is contained in:
Jitendra Bhivare 2016-10-13 12:08:48 +05:30 • committed by Martin K. Petersen
commit 4fa507992f

View file

@ -791,9 +791,9 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
free_task:
/* regular RX path uses back_lock */
spin_lock_bh(&session->back_lock);
spin_lock(&session->back_lock);
__iscsi_put_task(task);
spin_unlock_bh(&session->back_lock);
spin_unlock(&session->back_lock);
return NULL;
}