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Date:   Wed, 15 Jan 2020 15:27:38 -0800
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Vitaly Kuznetsov <vkuznets@redhat.com>
Cc:     kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        linux-kernel@vger.kernel.org, Liran Alon <liran.alon@oracle.com>,
        Roman Kagan <rkagan@virtuozzo.com>
Subject: Re: [PATCH RFC 2/3] x86/kvm/hyper-v: move VMX controls sanitization
 out of nested_enable_evmcs()
Message-ID: <20200115232738.GB18268@linux.intel.com>
References: <20200115171014.56405-1-vkuznets@redhat.com>
 <20200115171014.56405-3-vkuznets@redhat.com>
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On Wed, Jan 15, 2020 at 06:10:13PM +0100, Vitaly Kuznetsov wrote:
> With fine grained VMX feature enablement QEMU>=4.2 tries to do KVM_SET_MSRS
> with default (matching CPU model) values and in case eVMCS is also enabled,
> fails.

As in, Qemu is blindly throwing values at KVM and complains on failure?
That seems like a Qemu bug, especially since Qemu needs to explicitly do
KVM_CAP_HYPERV_ENLIGHTENED_VMCS to enable eVMCS.