Re: [PATCH v2 3/3] KVM: VMX: enable guest access to LMCE related MSRs

[Paolo Bonzini]

On 20/06/2016 03:49, Haozhong Zhang wrote:
> Thanks for the explanation!
> 
> If we disable LMCE in QEMU by default (even for -cpu host), will it
> still be a problem? That is,
> 
> - pc-2.7 can continue to run on old kernels unless users explicitly
>   require LMCE
> 
> - existing libvirt VM configurations can continue to work on pc-2.7
>   because LMCE is not specified in those configurations and are
>   disabled by default (i.e. no requirement for new kernels)
> 
> - existing QEMU configurations/scripts using pc alias can continue to
>   work on pc-27 for the same reason above.

Yes, that would be fine.  "-cpu host" can leave LMCE enabled if
supported by the kernel.

Paolo