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Date: Fri, 26 Apr 2013 15:01:19 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Yinghai Lu <yinghai@kernel.org>
CC: Kees Cook <keescook@chromium.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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        Eric Northup <digitaleric@google.com>,
        Dan Rosenberg <drosenberg@vsecurity.com>,
        Julien Tinnes <jln@google.com>, Will Drewry <wad@chromium.org>
Subject: Re: [PATCH 5/6] x86: kaslr: select memory region from e820 maps
References: <1367003005-5560-1-git-send-email-keescook@chromium.org> <1367003005-5560-6-git-send-email-keescook@chromium.org> <CAE9FiQVA17TGuY5_DFGUL8OSMLx+yJQV1fhe7JDkaoq1a9-oSw@mail.gmail.com>
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On 04/26/2013 02:51 PM, Yinghai Lu wrote:
> On Fri, Apr 26, 2013 at 12:03 PM, Kees Cook <keescook@chromium.org> wrote:
>> This chooses the largest contiguous RAM region for the KASLR offset
>> to live in.
>>
>> Signed-off-by: Kees Cook <keescook@chromium.org>
>> ---
>> v2:
>>  - make sure to exclude e820 regions outside the 32-bit memory range.
> 
> Do you need to execlude range that is used for initrd and possible
> command_line and boot_param ?
> 

Yes, those would have to be excluded.  For correctness the mem= and
memmap= options should also be taken into account.

	-hpa