IB/srp: Fix crash in srp_reconnect_target

Protect against srp_reset_device() clearing the req_queue while
srp_reconnect_target() is in progress (note that state change at
the top of srp_reconnect_target() is not sufficient for this since
srp_reset_device() ignores the state).

Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 8f472e7113b41afcd4b35f35a0ea7ae0f55d93fe..ff94e4e326913f828a254950a4661ecee45a6d77 100644 (file)
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -526,8 +526,10 @@ static int srp_reconnect_target(struct srp_target_port *target)
        while (ib_poll_cq(target->cq, 1, &wc) > 0)
                ; /* nothing */
 
+       spin_lock_irq(target->scsi_host->host_lock);
        list_for_each_entry_safe(req, tmp, &target->req_queue, list)
                srp_reset_req(target, req);
+       spin_unlock_irq(target->scsi_host->host_lock);
 
        target->rx_head  = 0;
        target->tx_head  = 0;