On Fri, Feb 19, 2021 at 12:21:36PM +0100, Cornelia Huck wrote: > On Tue, 16 Feb 2021 12:18:30 +0100 > Cornelia Huck <coh...@redhat.com> wrote: > > > The virtio standard specifies that any non-transitional device must > > reject commands prior to revision setting (which we do) and else > > assume revision 0 (legacy) if the driver sends a non-revision-setting > > command first. We neglected to do the latter. > > > > Fortunately, nearly everything worked as intended anyway; the only > > problem was not properly rejecting revision setting after some other > > command had been issued. Easy to fix by setting revision to 0 if > > we see a non-revision command on a legacy-capable revision-less > > device. > > > > Signed-off-by: Cornelia Huck <coh...@redhat.com> > > --- > > hw/s390x/virtio-ccw.c | 21 ++++++++++++++------- > > 1 file changed, 14 insertions(+), 7 deletions(-) > > I now have: > > Author: Cornelia Huck <coh...@redhat.com> > Date: Tue Feb 16 12:18:30 2021 +0100 > > virtio-ccw: commands on revision-less devices > > The virtio standard specifies that any non-transitional device must > reject commands prior to revision setting (which we do). Devices > that are transitional need to assume revision 0 (legacy) if the > driver sends a non-revision-setting command first in order to > support legacy drivers. We neglected to do the latter. > > Fortunately, nearly everything worked as intended anyway; the only > problem was not properly rejecting revision setting after some other > command had been issued. Easy to fix by setting revision to 0 if > we see a non-revision command on a legacy-capable revision-less > device. > > Found by code inspection, not observed in the wild. > > Signed-off-by: Cornelia Huck <coh...@redhat.com> > Reviewed-by: Thomas Huth <th...@redhat.com> > Reviewed-by: Michael S. Tsirkin <m...@redhat.com> > Acked-by: Halil Pasic <pa...@linux.ibm.com> > Message-Id: <20210216111830.1087847-1-coh...@redhat.com> > > Any objections?
Acked-by: Michael S. Tsirkin <m...@redhat.com>
