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To: David Howells <dhowells@redhat.com>, Andy Lutomirski <luto@amacapital.net>
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From: Greg Ungerer <gregungerer@westnet.com.au>
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Date: Tue, 24 Jan 2017 09:26:03 +1000
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Cc: Josh Armour <jarmour@google.com>, Greg KH <gregkh@linuxfoundation.org>,
	"ksummit-discuss@lists.linuxfoundation.org"
	<ksummit-discuss@lists.linuxfoundation.org>,
	"linux-mm@kvack.org" <linux-mm@kvack.org>
Subject: Re: [Ksummit-discuss] security-related TODO items?
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On 24/01/17 06:36, David Howells wrote:
> Andy Lutomirski <luto@amacapital.net> wrote:
[snip]
>>>  (6) NOMMU could be particularly tricky.  For ELF-FDPIC at least, the stack
>>>      size is set in the binary.  OTOH, you wouldn't have to relocate the
>>>      pre-loader - you'd just mmap it MAP_PRIVATE and execute in place.
>>
>> For nommu, forget about it.
> 
> Why?  If you do that, you have to have bimodal binfmts.  Note that the
> ELF-FDPIC binfmt, at least, can be used for both MMU and NOMMU environments.
> This may also be true of FLAT.

It is true for FLAT as well, they can run on both MMU an noMMU.

Regards
Greg