From 812494d9a0cacf77e0a538be18183c7b471812aa Mon Sep 17 00:00:00 2001 From: chas williams <3chas3@gmail.com> Date: Wed, 16 Sep 2015 16:28:25 -0400 Subject: [PATCH] xen-netfront: always set num queues if possible If netfront connects with two (or more) queues and then reconnects with only one queue it fails to delete or rewrite the multi-queue-num-queues key and netback will try to use the wrong number of queues. Always write the num-queues field if the backend has multi-queue support. Signed-off-by: Chas Williams <3chas3@gmail.com> Signed-off-by: David S. Miller --- drivers/net/xen-netfront.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index f821a97d7827..9bf63c27a9b7 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -1819,19 +1819,22 @@ again: goto destroy_ring; } - if (num_queues == 1) { - err = write_queue_xenstore_keys(&info->queues[0], &xbt, 0); /* flat */ - if (err) - goto abort_transaction_no_dev_fatal; - } else { + if (xenbus_exists(XBT_NIL, + info->xbdev->otherend, "multi-queue-max-queues")) { /* Write the number of queues */ - err = xenbus_printf(xbt, dev->nodename, "multi-queue-num-queues", - "%u", num_queues); + err = xenbus_printf(xbt, dev->nodename, + "multi-queue-num-queues", "%u", num_queues); if (err) { message = "writing multi-queue-num-queues"; goto abort_transaction_no_dev_fatal; } + } + if (num_queues == 1) { + err = write_queue_xenstore_keys(&info->queues[0], &xbt, 0); /* flat */ + if (err) + goto abort_transaction_no_dev_fatal; + } else { /* Write the keys for each queue */ for (i = 0; i < num_queues; ++i) { queue = &info->queues[i]; -- 2.20.1