From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:58311) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVGCt-0003zD-GL for qemu-devel@nongnu.org; Thu, 25 Apr 2013 03:03:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UVGCo-0006TK-RO for qemu-devel@nongnu.org; Thu, 25 Apr 2013 03:03:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13250) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UVGCo-0006TA-JK for qemu-devel@nongnu.org; Thu, 25 Apr 2013 03:02:58 -0400 Message-ID: <5178D514.5090600@redhat.com> Date: Thu, 25 Apr 2013 15:02:44 +0800 From: Jason Wang MIME-Version: 1.0 References: <1366870889-950-1-git-send-email-jasowang@redhat.com> <20130425065953.GB7299@redhat.com> In-Reply-To: <20130425065953.GB7299@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] virtio-net: count VIRTIO_NET_F_MAC when calculating config_len List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, Jesse Larrew On 04/25/2013 02:59 PM, Michael S. Tsirkin wrote: > On Thu, Apr 25, 2013 at 02:21:29PM +0800, Jason Wang wrote: >> 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 >> Signed-off-by: Jason Wang >> --- >> 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; > This would be cleaner: > host_features |= (1 << VIRTIO_NET_F_MAC); > > no need for a comment then. Sure, will send V2. >> 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