From 23bfaf77fa801ba30bb136de7cec47728eb02f4b Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Mon, 25 Mar 2019 11:40:36 +0800 Subject: vhost_net: don't set backend for the uninitialized virtqueue We used to set backend unconditionally, this won't work for some guests (e.g windows driver) who may not initialize all virtqueues. For kernel backend, this will fail since it may try to validate the rings during setting backend. Fixing this by simply skipping the backend set when we find desc is not ready. Reviewed-by: Michael S. Tsirkin Signed-off-by: Jason Wang --- hw/net/vhost_net.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'hw/net/vhost_net.c') diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index be3cc88370..a6b719035c 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -244,6 +244,11 @@ static int vhost_net_start_one(struct vhost_net *net, qemu_set_fd_handler(net->backend, NULL, NULL, NULL); file.fd = net->backend; for (file.index = 0; file.index < net->dev.nvqs; ++file.index) { + if (!virtio_queue_enabled(dev, net->dev.vq_index + + file.index)) { + /* Queue might not be ready for start */ + continue; + } r = vhost_net_set_backend(&net->dev, &file); if (r < 0) { r = -errno; @@ -256,6 +261,11 @@ fail: file.fd = -1; if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) { while (file.index-- > 0) { + if (!virtio_queue_enabled(dev, net->dev.vq_index + + file.index)) { + /* Queue might not be ready for start */ + continue; + } int r = vhost_net_set_backend(&net->dev, &file); assert(r >= 0); } -- cgit 1.4.1