Am 16.08.2012 10:57, schrieb Stefan Hajnoczi: > QEMU has a policy of keeping a stable guest device ABI. When new guest device > features are introduced they must not change hardware info seen by existing > guests. This is important because operating systems or applications may > "fingerprint" the hardware and refuse to run when the hardware changes. To > always get the latest guest device ABI, run with x86 machine type "pc". > > This patch hides the new VIRTIO_BLK_F_CONFIG_WCE virtio feature bit from > existing machine types. Only pc-1.2 and later will expose this feature > by default. > > For more info on the VIRTIO_BLK_F_CONFIG_WCE feature bit, see: > > commit 13e3dce068773c971ff2f19d986378c55897c4a3 > Author: Paolo Bonzini <pbonz...@redhat.com> > Date: Thu Aug 9 16:07:19 2012 +0200 > > virtio-blk: support VIRTIO_BLK_F_CONFIG_WCE > > Also rename VIRTIO_BLK_F_WCACHE to VIRTIO_BLK_F_WCE for consistency with > the spec. > > Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> > Signed-off-by: Kevin Wolf <kw...@redhat.com> > > Anthony Liguori <aligu...@us.ibm.com> reported: > > This broke qemu-test because it changed the pc-1.0 machine type: > > Setting guest RANDOM seed to 47167 > *** Running tests *** > Running test /tests/finger-print.sh... OK > --- fingerprints/pc-1.0.x86_64 2011-12-18 13:08:40.000000000 -0600 > +++ fingerprint.txt 2012-08-12 13:30:48.000000000 -0500 > @@ -55,7 +55,7 @@ > /sys/bus/pci/devices/0000:00:06.0/subsystem_device=0x0002 > /sys/bus/pci/devices/0000:00:06.0/class=0x010000 > /sys/bus/pci/devices/0000:00:06.0/revision=0x00 > -/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x710006d4 > +/sys/bus/pci/devices/0000:00:06.0/virtio/host-features=0x71000ed4 > /sys/class/dmi/id/bios_vendor=Bochs > /sys/class/dmi/id/bios_date=01/01/2007 > /sys/class/dmi/id/bios_version=Bochs > Guest fingerprint changed for pc-1.0! > > Reported-by: Anthony Liguori <aligu...@us.ibm.com> > Signed-off-by: Stefan Hajnoczi <stefa...@linux.vnet.ibm.com> > --- > Anthony, does this fix your test case?
Looks good to me, but I think I'll wait for Anthony to check it. Kevin
