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Date: Fri, 24 Mar 2017 10:40:34 +0100
From: Borislav Petkov <bp@alien8.de>
To: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>, Dave Young <dyoung@redhat.com>,
        Baoquan He <bhe@redhat.com>,
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        Thomas Garnier <thgarnie@google.com>,
        Kees Cook <keescook@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Masahiro Yamada <yamada.masahiro@socionext.com>,
        Bhupesh Sharma <bhsharma@redhat.com>
Subject: Re: [PATCH v2] x86/mm/KASLR: EFI region is mistakenly included into
 KASLR VA space for randomization
Message-ID: <20170324094034.2afxgg43wlezdka5@pd.tnic>
References: <1490331592-31860-1-git-send-email-bhe@redhat.com>
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On Fri, Mar 24, 2017 at 09:37:36AM +0000, Ard Biesheuvel wrote:
> No. It is the firmware's EFI code, and the virtual translation applied
> by the OS is made known to the firmware by means of a call into the
> runtime service SetVirtualAddressMap().

We can still randomize within those 64G before calling
SetVirtualAddressMap(). The question is, do we want to or need to, even?

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.