Re: [RESEND RFC 0/2] Paravirtualized Control Register pinning

From: Paolo Bonzini
Date: Mon Dec 23 2019 - 12:09:32 EST


On 23/12/19 15:48, Liran Alon wrote:
>> Should userspace expose the CR pining CPUID feature bit, it must zero CR
>> pinned MSRs on reboot. If it does not, it runs the risk of having the
>> guest enable pinning and subsequently cause general protection faults on
>> next boot due to early boot code setting control registers to values
>> which do not contain the pinned bits.
>
> Why reset CR pinned MSRs by userspace instead of KVM INIT handling?

Most MSRs are not reset by INIT, are they?

Paolo