Re: [PATCH v3 0/5] KVM: nVMX: Fix Windows 11 + WSL2 + Enlightened VMCS

[Vitaly Kuznetsov]

Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> writes:

> Changes since v2 [Sean]:
> - Tweak a comment in PATCH5.
> - Add Reviewed-by: tags to PATCHes 3 and 5.
>
> Original description:
>
> Windows 11 with enabled Hyper-V role doesn't boot on KVM when Enlightened
> VMCS interface is provided to it. The observed behavior doesn't conform to
> Hyper-V TLFS. In particular, I'm observing 'VMREAD' instructions trying to
> access field 0x4404 ("VM-exit interruption information"). TLFS, however, is
> very clear this should not be happening:
>
> "Any VMREAD or VMWRITE instructions while an enlightened VMCS is active is
> unsupported and can result in unexpected behavior."
>
> Microsoft confirms this is a bug in Hyper-V which is supposed to get fixed
> eventually. For the time being, implement a workaround in KVM allowing 
> VMREAD instructions to read from the currently loaded Enlightened VMCS.
>
> Patches 1-2 are unrelated fixes to VMX feature MSR filtering when eVMCS is
> enabled. Patches 3 and 4 are preparatory changes, patch 5 implements the
> workaround.
>

Paolo,

would it be possible to pick this up for 5.17? Technically, this is a
"fix", even if the bug itself is not in KVM)

-- 
Vitaly