Commit 14f9b664 (hw/virtio-net.c: set config size using host features) tries to calculate config size based on the host features. But it forgets the VIRTIO_NET_F_MAC were always set for qemu later. This will lead a zero config len for virtio-net device when both VIRTIO_NET_F_STATUS and VIRTIO_NET_F_MQ were disabled form command line. Then qemu will crash when user tries to read the config of virtio-net.
Fix this by counting VIRTIO_NET_F_MAC and make sure the config at least contains the mac address. Cc: Jesse Larrew <jlar...@linux.vnet.ibm.com> Signed-off-by: Jason Wang <jasow...@redhat.com> --- hw/net/virtio-net.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 70c8fce..33a70ef 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1264,7 +1264,8 @@ static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx, void virtio_net_set_config_size(VirtIONet *n, uint32_t host_features) { - int i, config_size = 0; + /* VIRTIO_NET_F_MAC can't be disabled from qemu side */ + int i, config_size = feature_sizes[0].end; for (i = 0; feature_sizes[i].flags != 0; i++) { if (host_features & feature_sizes[i].flags) { config_size = MAX(feature_sizes[i].end, config_size); -- 1.7.1