Re: [PATCH 0/5] KVM: SVM: nSVM: Implement Enlightened MSR-Bitmap for Hyper-V-on-KVM and fix it for KVM-on-Hyper-V

Vitaly Kuznetsov
2022-02-01T14:31:49Z

Paolo Bonzini <pbonzini@redhat.com> writes:

> On 12/20/21 16:21, Vitaly Kuznetsov wrote:
>> Enlightened MSR-Bitmap feature implements a PV protocol for L0 and L1
>> hypervisors to collaborate and skip unneeded updates to MSR-Bitmap.
>> KVM implements the feature for KVM-on-Hyper-V but it seems there was
>> a flaw in the implementation and the feature may not be fully functional.
>> PATCHes 1-2 fix the problem. The rest of the series implements the same
>> feature for Hyper-V-on-KVM.
>>
>> Vitaly Kuznetsov (5):
>> KVM: SVM: Drop stale comment from
>> svm_hv_vmcb_dirty_nested_enlightenments()
>> KVM: SVM: hyper-v: Enable Enlightened MSR-Bitmap support for real
>> KVM: nSVM: Track whether changes in L0 require MSR bitmap for L2 to be
>> rebuilt
>> KVM: x86: Make kvm_hv_hypercall_enabled() static inline
>> KVM: nSVM: Implement Enlightened MSR-Bitmap feature
>>
>> arch/x86/kvm/hyperv.c | 12 +--------
>> arch/x86/kvm/hyperv.h | 6 ++++-
>> arch/x86/kvm/svm/nested.c | 47 ++++++++++++++++++++++++++++-----
>> arch/x86/kvm/svm/svm.c | 3 ++-
>> arch/x86/kvm/svm/svm.h | 16 +++++++----
>> arch/x86/kvm/svm/svm_onhyperv.h | 12 +++------
>> 6 files changed, 63 insertions(+), 33 deletions(-)
>>
>
> Queued 3-5 now, but it would be nice to have some testcases.
>

Thanks, indeed, I'll try to draft something up, both for nVMX and nSVM.

--
Vitaly