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Date: Wed, 14 Oct 2015 17:35:22 +0200
From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>, Matt Fleming <matt@codeblueprint.co.uk>,
        Stephen Smalley <sds@tycho.nsa.gov>, X86 ML <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Andy Lutomirski <luto@kernel.org>,
        Denys Vlasenko <dvlasenk@redhat.com>, Brian Gerst <brgerst@gmail.com>,
        "linux-efi@vger.kernel.org" <linux-efi@vger.kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: Re: [PATCH v2] x86/mm: warn on W+x mappings
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On Wed, Oct 14, 2015 at 08:30:48AM -0700, Andy Lutomirski wrote:
> Can we just unmap these things until someone tries to do an EFI call,
> and then unmap them again after the call returns?  We already switch
> pgds for EFI IIRC.

hpa did mention an EFI-aware page fault handler at the time. I guess we
could do that too...

-- 
Regards/Gruss,
    Boris.

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