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Message-ID: <a20344fd-8130-013e-e773-acae81aad55a@intel.com>
Date:   Wed, 7 Jun 2023 08:31:24 -0700
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Subject: Re: [PATCH v2] x86/mm: Fix PAT bit missing from page protection
 modify mask
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To:     Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>
Cc:     Juergen Gross <jgross@suse.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org,
        Andi Shyti <andi.shyti@linux.intel.com>,
        intel-gfx@lists.freedesktop.org
References: <20230607152308.125787-2-janusz.krzysztofik@linux.intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20230607152308.125787-2-janusz.krzysztofik@linux.intel.com>
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On 6/7/23 08:23, Janusz Krzysztofik wrote:
> 
> Extend bitmask used by pgprot_modify() for selecting bits to be preserved
> with _PAGE_PAT bit.  However, since that bit can be reused as _PAGE_PSE,
> and the _PAGE_CHG_MASK symbol, primarly used by pte_modify(), is likely
> intentionally defined with that bit not set, keep that symbol unchanged.

I'm really having a hard time parsing what that last sentence is saying.

Could you try again, please?