diff options
authorFam Zheng <famz@redhat.com>2015-07-15 11:02:27 +0800
committerMichael S. Tsirkin <mst@redhat.com>2015-07-20 14:19:41 +0300
commit38705bb57bf1cd9e3f837cf11bcdee3876786c07 (patch)
parent9a2a66238e3bf2b681d6321c4667a2d589c8ebed (diff)
virtio-net: Flush incoming queues when DRIVER_OK is being set
This patch fixes network hang after "stop" then "cont", while network packets keep arriving. Tested both manually (tap, host pinging guest) and with Jason's qtest series (plus his "[PATCH 2.4] socket: pass correct size in net_socket_send()" fix). As virtio_net_set_status is called when guest driver is setting status byte and when vm state is changing, it is a good opportunity to flush queued packets. This is necessary because during vm stop the backend (e.g. tap) would stop rx processing after .can_receive returns false, until the queue is explicitly flushed or purged. The other interesting condition in .can_receive, virtio_queue_ready(), is handled by virtio_net_handle_rx() when guest kicks; the 3rd condition is invalid queue index which doesn't need flushing. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
1 files changed, 9 insertions, 1 deletions
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 9f7e91ddce..e1d9cbf722 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -162,6 +162,8 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
virtio_net_vhost_status(n, status);
for (i = 0; i < n->max_queues; i++) {
+ NetClientState *ncs = qemu_get_subqueue(n->nic, i);
+ bool queue_started;
q = &n->vqs[i];
if ((!n->multiqueue && i != 0) || i >= n->curr_queues) {
@@ -169,12 +171,18 @@ static void virtio_net_set_status(struct VirtIODevice *vdev, uint8_t status)
} else {
queue_status = status;
+ queue_started =
+ virtio_net_started(n, queue_status) && !n->vhost_started;
+ if (queue_started) {
+ qemu_flush_queued_packets(ncs);
+ }
if (!q->tx_waiting) {
- if (virtio_net_started(n, queue_status) && !n->vhost_started) {
+ if (queue_started) {
if (q->tx_timer) {
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);