From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 14 Nov 2014 09:46:42 -0800 From: Greg Kroah-Hartman To: Ben Hutchings Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, "David S. Miller" Subject: Re: [PATCH 3.17 023/319] drivers/net: Disable UFO through virtio Message-ID: <20141114174642.GA2895@kroah.com> References: <20141112010952.553519040@linuxfoundation.org> <20141112010956.540146480@linuxfoundation.org> <1415826239.3398.113.camel@decadent.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1415826239.3398.113.camel@decadent.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Wed, Nov 12, 2014 at 09:03:59PM +0000, Ben Hutchings wrote: > On Wed, 2014-11-12 at 10:12 +0900, Greg Kroah-Hartman wrote: > > 3.17-stable review patch. If anyone has any objections, please let me know. > > > > ------------------ > > > > From: Ben Hutchings > > > > [ Upstream commit 3d0ad09412ffe00c9afa201d01effdb6023d09b4 ] > > > > IPv6 does not allow fragmentation by routers, so there is no > > fragmentation ID in the fixed header. UFO for IPv6 requires the ID to > > be passed separately, but there is no provision for this in the virtio > > net protocol. > > > > Until recently our software implementation of UFO/IPv6 generated a new > > ID, but this was a bug. Now we will use ID=0 for any UFO/IPv6 packet > > passed through a tap, which is even worse. > > > > Unfortunately there is no distinction between UFO/IPv4 and v6 > > features, so disable UFO on taps and virtio_net completely until we > > have a proper solution. > [...] > > Please drop this patch for 3.14 and 3.17. It causes problems for > migration of VMs and we're probably going to revert part of this. The > following patch ("drivers/net, ipv6: Select IPv6 fragment idents for > virtio UFO packets") might no longer apply, in which case you can drop > that as well until we have this sorted out upstream. Oops, I missed this for 3.14-stable, I'll go revert that as the first patch to be queued up for the next round there. I've dropped this from 3.17-stable, and the patch "drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets" still applied with some fuzz, I'll do a test build to ensure I didn't break anything there. thanks, greg k-h