Subject: Re: [PATCH v5 1/2] x86/mm: add a function to check if a pfn is UC/UC-
To: kvm@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org,
        rkrcmar@redhat.com, Xiao Guangrong <xiaoguangrong.eric@gmail.com>,
        Dan Williams <dan.j.williams@intel.com>,
        ivan.d.cuevas.escareno@intel.com, karthik.kumar@intel.com,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Olif Chapman <olif.chapman@oracle.com>,
        Mikulas Patocka <mpatocka@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Borislav Petkov <bp@suse.de>,
        Tom Lendacky <thomas.lendacky@amd.com>
References: <20171108075630.16991-1-haozhong.zhang@intel.com>
 <20171108075630.16991-2-haozhong.zhang@intel.com>
 <2da7d38c-8135-a722-8d93-f3d1a618b12e@redhat.com>
 <20171219024053.b5ckuwevnm2ydzef@hz-desktop>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <6541e56d-a5d8-641e-99e8-cbc7bce6da3a@redhat.com>
Date: Tue, 19 Dec 2017 11:42:20 +0100
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On 19/12/2017 03:40, Haozhong Zhang wrote:
>> As discussed in the reply to v2, this should include WC too.  The
>> function name could become something like pat_pfn_downgraded_by_uc_mtrr.
>
> Or shall we just expose lookup_memtype(), and keep all other logic in
> KVM? The function name still looks strange somehow, and the check of
> memory type makes more sense and would be easier to understand in the
> context of KVM.

I agree that it's a bit strange, but I don't want to go against the
suggestions of the x86 maintainer.

Paolo