On 26.09.2017 15:36, Christian Borntraeger wrote: > With newer kernels that do support the ais feature (4.13) a qemu 2.11 > will not only enable the ais feature for the 2.11 machine, but also > for a <=2.10 compat machine. As this feature is not available in > QEMU <=2.9 (and QEMU 2.10.1), this guest will fail to migrate > back to an older qemu like 2.9 with: > > _snip_ > error while loading state for instance 0x0 of device 's390-flic' > _snip_ > > making the whole compat machine dis-functional. As a permanent fix, we > need to fence the ais feature for machines <= 2.10 > > Due to ais being enabled on 2.10.0 (fixed in 2.10.1) this will prevent > migration of ais-enabled guests from 2.10.0 with > > _snip_ > qemu-system-s390x: Failed to load s390-flic/ais:tmp > qemu-system-s390x: error while loading state for instance 0x0 of device > 's390-flic' > qemu-system-s390x: load of migration failed: Function not implemented > _snip_ > > Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com> > Cc: Yi Min Zhao <zyi...@linux.vnet.ibm.com> > Cc: Dr. David Alan Gilbert <dgilb...@redhat.com> > --- > hw/intc/s390_flic_kvm.c | 4 +++-
As discussed, I think we should use cpu_model_allowed() instead. -- Thanks, David
