Re: [PATCH 01/16] x86/intel: Initialize IA32_FEATURE_CONTROL MSR at boot

[Paolo Bonzini]

On 04/10/19 23:56, Sean Christopherson wrote:
> Always lock IA32_FEATURE_CONTROL if it exists, even if the CPU doesn't
> support VMX, so that other existing and future kernel code that queries
> IA32_FEATURE_CONTROL can assume it's locked.

Possibly stupid question: why bother locking it?  It makes sense to lock
the MSR bits to _off_ in the firmware, but if the BIOS hasn't locked it,
why should the OS?

It seems to me that locking introduces a lot of complication.

Paolo