KVM: nVMX: Filter out all unsupported controls when eVMCS was activated
Windows Server 2022 with Hyper-V role enabled failed to boot on KVM when enlightened VMCS is advertised. Debugging revealed there are two exposed secondary controls it is not happy with: SECONDARY_EXEC_ENABLE_VMFUNC and SECONDARY_EXEC_SHADOW_VMCS. These controls are known to be unsupported, as there are no corresponding fields in eVMCSv1 (see the comment above EVMCS1_UNSUPPORTED_2NDEXEC definition). Previously, commit 31de3d25 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()") introduced the required filtering mechanism for VMX MSRs but for some reason put only known to be problematic (and not full EVMCS1_UNSUPPORTED_* lists) controls there. Note, Windows Server 2022 seems to have gained some sanity check for VMX MSRs: it doesn't even try to launch a guest when there's something it doesn't like, nested_evmcs_check_controls() mechanism can't catch the problem. Let's be bold this time and instead of playing whack-a-mole just filter out all unsupported controls from VMX MSRs. Fixes: 31de3d25 ("x86/kvm/hyper-v: move VMX controls sanitization out of nested_enable_evmcs()") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210907163530.110066-1-vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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