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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     "Tian, Kevin" <kevin.tian@intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        "Nakajima, Jun" <jun.nakajima@intel.com>
Cc:     "Liu, Jing2" <jing2.liu@intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        "x86@kernel.org" <x86@kernel.org>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Jing Liu <jing2.liu@linux.intel.com>,
        "seanjc@google.com" <seanjc@google.com>,
        "Cooper, Andrew" <andrew.cooper3@citrix.com>,
        "Bae, Chang Seok" <chang.seok.bae@intel.com>
Subject: RE: Thoughts of AMX KVM support based on latest kernel
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 <878rxn6h6t.ffs@tglx> <16BF8BE6-B7B1-4F3E-B972-9D82CD2F23C8@intel.com>
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Date:   Wed, 17 Nov 2021 13:24:19 +0100
Message-ID: <87tugb3r7w.ffs@tglx>
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Tian,

On Wed, Nov 17 2021 at 10:15, Tian, Kevin wrote:
> We are not sure whether such trick is worthwhile, since a sane
> guest shouldn't set XFD[AMX]=1 before storing the AMX state. This
> is why we want to seek SDM change to mark out that the software
> should not assume XTILEDATA is still valid when XFD[AMX]=1.

Yes, please. Anything else is just causing too much hackery for no
value.

Thanks,

        tglx