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From: Mike Frysinger <vapier.adi@gmail.com>
Date: Wed, 8 Jul 2009 14:48:51 -0400
Message-ID: <8bd0f97a0907081148vc716eeepfdaf8178b1ecbce1@mail.gmail.com>
Subject: Re: [PATCH] FDPIC: Ignore the loader's PT_GNU_STACK when calculating 
	the stack size
To: Pavel Machek <pavel@ucw.cz>
Cc: David Howells <dhowells@redhat.com>, rgetz@blackfin.uclinux.org,
       lethal@linux-sh.org, gerg@uclinux.org,
       uclinux-dist-devel@blackfin.uclinux.org, linux-kernel@vger.kernel.org
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On Fri, Jul 3, 2009 at 23:34, Pavel Machek wrote:
> On Wed 2009-07-08 12:01:40, David Howells wrote:
>> Pavel Machek <pavel@ucw.cz> wrote:
>>
>> > The patch seems wrong to me; loader needs the stack, too, right?
>> >
>> > What about making sure that the loader specifies reasonable stack
>> > size, instead?
>>
>> The loader doesn't need its own stack, unless it _is_ the executable.  It uses
>> the executable's stack.  The problem is that the executable and the loader can
>> both specify the stack size for NOMMU, but which one do we pick, or do we
>> consider both.
>
> Imageine loader needs 64K, while executable only needs 4K. You surely
> want to execute it with 64K stack, because it will not fit into 4K?

i really dont think this is realistic.  there is exactly one ldso that
everyone uses under FDPIC ELF, and it needs a very minuscule stack.
-mike
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