Subject: Re: [PATCH 9/8] KVM: x86: limit MSR_IA32_SPEC_CTRL access based on
 CPUID availability
To: Liran Alon <liran.alon@oracle.com>
Cc: jmattson@google.com, x86@kernel.org, dwmw@amazon.co.uk,
        bp@alien8.de, aliguori@amazon.com, thomas.lendacky@amd.com,
        rkrcmar@redhat.com, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
References: <901c4def-b0a4-42aa-9a88-cae3c3f64cf0@default>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <4f15b6d7-6f1e-f578-2310-6dfb639b5771@redhat.com>
Date: Tue, 9 Jan 2018 17:11:23 +0100
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On 09/01/2018 16:58, Liran Alon wrote:
> 
> The only thing I a bit dislike is that currently these MSRs are always pass-through to guest and therefore
> there is no case vmx_set_msr() is called with !msr_info->host_initiated.
> Don't you think we should BUG_ON(!msr_info->host_initiated)?

All this is in flux.  We'll probably get per-VCPU MSR bitmaps anyway
before this patch (which is not part of the initial, minimal fix) is
committed.

Paolo