Re: [PATCH 0/3] KVM: x86: Clean up RESET "emulation"

From: Paolo Bonzini
Date: Fri Sep 17 2021 - 13:37:32 EST


On 17/09/21 19:34, Sean Christopherson wrote:
but I do like it so yes, that was it. Especially the fact that init_vmcb now
has a single caller. I would further consider moving save area initialization
to *_vcpu_reset, and keeping the control fields in init_vmcb/vmcs. That would
make it easier to relate the two functions to separate parts of the manuals.

I like the idea, but I think I'd prefer to tackle that at the same time as generic
support for handling MSRs at RESET/INIT.

No problem, just roughly sketching some ideas for the future. But you're absolutely right that some MSRs have effects on the control areas rather than the save area (and some have effects on neither).

Thanks,

Paolo

E.g. instead of manually writing
vmcs.GUEST_SYSENTER_* at RESET, provide infrastruture to automagically run through
all emulated/virtualized at RESET and/or INIT as appropriate to initialize the
guest value.