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Subject: Re: [RFC PTI 1/3] x86/pti: Vastly simplify pgd synchronization
To: Andy Lutomirski <luto@kernel.org>
References: <cover.1512763129.git.luto@kernel.org>
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Cc: X86 ML <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Borislav Petkov <bp@alien8.de>, Brian Gerst <brgerst@gmail.com>,
        David Laight <David.Laight@aculab.com>,
        Kees Cook <keescook@chromium.org>,
        Peter Zijlstra <peterz@infradead.org>
From: Dave Hansen <dave.hansen@intel.com>
Message-ID: <87386e3b-f5a5-2481-9611-ce993314347a@intel.com>
Date: Fri, 8 Dec 2017 12:48:25 -0800
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On 12/08/2017 12:49 PM, Andy Lutomirski wrote:
>> if ((pgd.pgd & (_PAGE_USER|_PAGE_PRESENT)) &&
>>     (__supported_pte_mask & _PAGE_NX))
> I assume you mean pgd.pgd & (_PAGE_USER|_PAGE_PRESENT) ==
> (_PAGE_USER|_PAGE_PRESENT)?

Yeah.