On 04/07/2017 13:21, Laurent Vivier wrote: > On 04/07/2017 13:15, Greg Kurz wrote: >> On Tue, 4 Jul 2017 13:01:26 +0200 >> Laurent Vivier <lviv...@redhat.com> wrote: >> >>> Commit 5f3066d ("target/ppc: Allow workarounds for POWER9 DD1") >>> disables compatibility mode for POWER9 DD1 to allow to >>> boot on POWER9 DD1 host with KVM. >>> >>> As the workaround has been added in kvmppc_host_cpu_class_init(), >>> it applies only on CPU created with "-cpu host". >>> As we want to be able to use also "-cpu POWER9" on a POWER9 DD1 >>> host, this patch moves the workaround from kvmppc_host_cpu_class_init() >>> to init_proc_POWER9(). >>> >> >> As with ppc_cpu_initfn() in your previous version, init_proc_POWER9() is >> called for every CPU instance.. ie, all CPU will adjust the @pcr_supported >> class attribute... >> >> What about moving the workaround to ppc_POWER9_cpu_family_class_init() >> instead ? This would just require to expose mfpvr() in some header. > > I think I have already tried something like that, and I'm not sure the > PVR is already set at this level of the initialization. But I'm going to > try your patch.
oh, you check the host PVR, not the guest PVR. Well, I'm not sure it's a good idea to modify the guest CPU property according to the host CPU version. I let David to decide what is the best solution here... Thanks, Laurent