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From:   Jim Mattson <jmattson@google.com>
Date:   Tue, 30 May 2023 09:56:21 -0700
Message-ID: <CALMp9eSsx0WLd0RdkpXnDkyKGM2CZxSwgtfmFtH2hxYprfvhAA@mail.gmail.com>
Subject: Re: [PATCH v2] x86/msr: Allow unprivileged read access to some MSRs
To:     Tim Wiederhake <twiederh@redhat.com>
Cc:     Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, x86@kernel.org
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On Tue, May 30, 2023 at 3:28=E2=80=AFAM Tim Wiederhake <twiederh@redhat.com=
> wrote:
>
> Software such as qemu and libvirt require the raw content of some MSRs

Note that KVM doesn't return the raw value of IA32_ARCH_CAPABILITIES.
First, it filters out unsupported bits, and then it massages the
result a bit. See kvm_get_arch_capabilities(). Isn't this what qemu
actually wants?