Re: [Qemu-devel] [PATCH RFC for-2.2] virtio-blk: force 1st s/g to match header

["Marc Marí" <marc.mari.barcelo@gmail.com>]

El Fri, 28 Nov 2014 11:43:59 +0000
Stefan Hajnoczi <stefanha@gmail.com> escribió:
> On Fri, Nov 28, 2014 at 7:05 AM, Jason Wang <jasowang@redhat.com>
> wrote:
> >
> >
> > On Fri, Nov 28, 2014 at 9:16 AM, Fam Zheng <famz@redhat.com> wrote:
> >>
> >> On Thu, 11/27 23:13, Michael S. Tsirkin wrote:
> >>>
> >>>  On Thu, Nov 27, 2014 at 07:21:35PM +0000, Stefan Hajnoczi wrote:
> >>>  > On Thu, Nov 27, 2014 at 4:33 PM, Michael S. Tsirkin
> >>>  > <mst@redhat.com>
> >>> wrote:
> >>>  > > We leak cpu mappings when 1st s/g is not exactly the
> >>>  > > header. As we don't set ANY_LAYOUT, we can at this point
> >>>  > > simply assert the correct length.
> >>>  > >
> >>>  > > This will have to be fixed once ANY_LAYOUT is set.
> >>>  > >
> >>>  > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> >>>  > > ---
> >>>  > >
> >>>  > > Untested: posting for early feedback.
> >>>  >  > Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> >>>   Stefan, you are going to merge this for 2.2?
> >>>  Peter, if Stefan is merging this one, we can
> >>>  take Jason's patch for -net and that should be
> >>>  enough for 2.2.
> >>
> >>
> >> My test bot saw a failure of "make check":
> >>
> >> qemu-system-x86_64: virtio-blk request outhdr too long
> >> Broken pipe
> >> GTester: last random seed: R02S44c5a09d74c0603f0091ed20d1395121
> >> qemu-system-x86_64: virtio-blk request outhdr too long
> >> Broken pipe
> >> GTester: last random seed: R02Sfdf270c8e1ed75c1f2047e3f0fb89b88
> >> qemu-system-x86_64: virtio-blk request outhdr too long
> >> Broken pipe
> >> GTester: last random seed: R02Sd292c540929b963ed9d7d155f3db5452
> >> qemu-system-x86_64: virtio-blk request outhdr too long
> >> Broken pipe
> >> GTester: last random seed: R02Sfc775a34a844c39f376aa478eda7573f
> >> [vmxnet3][WR][vmxnet3_peer_has_vnet_hdr]: Peer has no virtio
> >> extension. Task offloads will be emulated.
> >> make: *** [check-qtest-x86_64] Error 1
> >>
> >> Fam
> >
> >
> > This probably because of the test itself.
> >
> > But anyway all kinds of guests (especially Windows drivers) need to
> > be tested.
> 
> Right, the test case explicitly tests different descriptor layouts,
> even though virtio-blk-pci does not set the ANY_LAYOUT feature bit.
> 
> Either the test case needs to check ANY_LAYOUT before using the
> 2-descriptor layout or it needs to expect QEMU to refuse (in this case
> exit(1), which is not very graceful).
> 
> The quick fix is to skip the 2-descriptor layout tests and re-enable
> them once virtio-blk actually supports ANY_LAYOUT.  Any objections?
> 
> Stefan

To be compliant with the specs, the test should check for ANY_LAYOUT
feature before testing with 2 descriptor layout. I'll add it with the
other changes pending for the test.

Marc