> -----Original Message----- > From: Yuanhan Liu [mailto:yuanhan....@linux.intel.com] > Sent: Friday, April 14, 2017 1:38 PM > To: Tan, Jianfeng > Cc: dev@dpdk.org; maxime.coque...@redhat.com > Subject: Re: [PATCH v2] net/virtio-user: fix cannot get initialized > > On Fri, Apr 14, 2017 at 04:35:57AM +0000, Tan, Jianfeng wrote: > > > > > > > -----Original Message----- > > > From: Yuanhan Liu [mailto:yuanhan....@linux.intel.com] > > > Sent: Friday, April 14, 2017 12:24 PM > > > To: Tan, Jianfeng > > > Cc: dev@dpdk.org; maxime.coque...@redhat.com > > > Subject: Re: [PATCH v2] net/virtio-user: fix cannot get initialized > > > > > > On Thu, Apr 13, 2017 at 10:11:27AM +0000, Jianfeng Tan wrote: > > > > The feature negotiation in virtio-user is proven to be broken, > > > > which results in device initialization failure. > > > > > > > > Originally, we get features from vhost backend, and remove those > > > > that are not supported. But when new feature is added, for example, > > > > VIRTIO_NET_F_MTU, we fail to remove this new feature. Then, this > > > > new feature will be negotiated, as both frontend and backend claim > > > > to support this feature. > > > > > > > > To fix it, we add a macro to record supported featues, as a filter > > > > to remove newly added features. > > > > > > Yes, this is much better! You now don't have to worry that virtio-user > > > will be broken every time we add a new feature. > > > > > > Applied to dpdk-next-virtio, with the title changed to "fix feature > > > negotitation". > > > > > > > Thanks. By the way, it's better backporting it to stable branches, however, > > I > forget to CC sta...@dpdk.org. > > As long as we don't backport new features to a stable release, there > should be no problem. > > Besides, the virtio-user features supported in this patch may not match > those supported by a stable release (say 16.11 LTS). For example, F_STATUS > is just added in this feature. Thus, I don't think it's a good candidate > for a stable release (though a backport could fix it).
Make sense. Thanks! Jianfeng
