s390/qeth: on channel error, reject further cmd requests

When the IRQ handler determines that one of the cmd IO channels has
failed and schedules recovery, block any further cmd requests from
being submitted. The request would inevitably stall, and prevent the
recovery from making progress until the request times out.

This sort of error was observed after Live Guest Relocation, where
the pending IO on the READ channel intentionally gets terminated to
kick-start recovery. Simultaneously the guest executed SIOCETHTOOL,
triggering qeth to issue a QUERY CARD INFO command. The command
then stalled in the inoperabel WRITE channel.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index 2a9afaf8f264cda9bd112c78cae2748f0a91ca9d..3653bea384705f1b1a27df45a94db33148194e1f 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -1174,6 +1174,7 @@ static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
                }
                rc = qeth_get_problem(cdev, irb);
                if (rc) {
+                       card->read_or_write_problem = 1;
                        qeth_clear_ipacmd_list(card);
                        qeth_schedule_recovery(card);
                        goto out;