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>
This commit is contained in:
Julian Wiedmann 2018-03-20 07:59:15 +01:00 committed by David S. Miller
parent 17bf8c9b3d
commit a6c3d93963

View file

@ -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;