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Date:   Thu, 23 Mar 2023 13:43:24 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Juergen Gross <jgross@suse.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>, xen-devel@lists.xenproject.org
Subject: Re: [PATCH v4 05/12] x86/xen: set MTRR state when running as Xen PV
 initial domain
Message-ID: <20230323124324.GHZBxJbOW1fvHOgiQ1@fat_crate.local>
References: <20230306163425.8324-1-jgross@suse.com>
 <20230306163425.8324-6-jgross@suse.com>
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On Mon, Mar 06, 2023 at 05:34:18PM +0100, Juergen Gross wrote:
> +	for (reg = 0; reg < MTRR_MAX_VAR_RANGES; reg++) {
> +		op.u.read_memtype.reg = reg;
> +		if (HYPERVISOR_platform_op(&op))
> +			break;
> +
> +		/*
> +		 * Only called in dom0, which has all RAM PFNs mapped at
> +		 * RAM MFNs, and all PCI space etc. is identity mapped.
> +		 * This means we can treat MFN == PFN regarding MTTR settings.
								^^^^

"MTRR"

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette