On 2019/3/25 下午5:56, Yuri Benditovich wrote:
Hi Jason, This seems ok now (4 previous patches + this one)
Thanks for the testing. Could you test with just this patch? Since even without 4 previous patch, we've already had the check through virtio_queue_get_desc_addr() in vhost_virtqueue_start().
On Mon, Mar 25, 2019 at 5:56 AM Jason Wang <jasow...@redhat.com> wrote: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. Signed-off-by: Jason Wang <jasow...@redhat.com> --- hw/net/vhost_net.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index be3cc88370..04fd924d15 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -221,6 +221,7 @@ static int vhost_net_start_one(struct vhost_net *net, VirtIODevice *dev) { struct vhost_vring_file file = { }; + hwaddr a; int r; net->dev.nvqs = 2; @@ -244,6 +245,13 @@ 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) { + a = virtio_queue_get_desc_addr(dev, + net->dev.vq_index + + file.index); + if (a == 0) { + /* Queue might not be ready for start */ + continue; + } r = vhost_net_set_backend(&net->dev, &file); if (r < 0) { r = -errno; @@ -256,6 +264,13 @@ fail: file.fd = -1; if (net->nc->info->type == NET_CLIENT_DRIVER_TAP) { while (file.index-- > 0) { + a = virtio_queue_get_desc_addr(dev, + net->dev.vq_index + + file.index); + if (a == 0) { + /* Queue might not be ready for start */ + continue; + } int r = vhost_net_set_backend(&net->dev, &file); assert(r >= 0); } -- 2.19.1
