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From:   Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date:   Fri, 21 Dec 2018 18:26:23 +0100
Message-ID: <CAKv+Gu91YsuK2QmWStPe84v8L7XD9x4cduTYgUjj3TPRfQckfw@mail.gmail.com>
Subject: Re: [tip:efi/core] x86/efi: Unmap EFI boot services code/data regions
 from efi_pgd
To:     Borislav Petkov <bp@alien8.de>
Cc:     "Prakhya, Sai Praneeth" <sai.praneeth.prakhya@intel.com>,
        Ingo Molnar <mingo@kernel.org>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
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        "eric.snowberg@oracle.com" <eric.snowberg@oracle.com>,
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        "Hansen, Dave" <dave.hansen@intel.com>,
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On Fri, 21 Dec 2018 at 18:13, Borislav Petkov <bp@alien8.de> wrote:
>
> On Fri, Dec 21, 2018 at 06:02:29PM +0100, Ard Biesheuvel wrote:
> > As far as I can tell, the SGI x86 UV platforms still rely on this, so
> > we're stuck with it for the foreseeable future.
>
> What happened with the old apple laptops which couldn't handle high
> virtual mappings and needed 1:1? We don't care anymore?
>

If that is the case (I wouldn't know) then yes, there is a second
reason why we need to keep this code.