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Date: Thu, 9 Jun 2011 08:48:47 +0200
From: Ingo Molnar <mingo@elte.hu>
To: pageexec@freemail.hu
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirski <luto@mit.edu>, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org,
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        Louis Rilling <Louis.Rilling@kerlabs.com>, Valdis.Kletnieks@vt.edu,
        Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH] x86-64, vsyscalls: Rename UNSAFE_VSYSCALLS to
 COMPAT_VSYSCALLS
Message-ID: <20110609064847.GC7734@elte.hu>
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* pageexec@freemail.hu <pageexec@freemail.hu> wrote:

> On 7 Jun 2011 at 11:56, Ingo Molnar wrote:
> 
> > Fedora was able to disable the fixed-address vdso in its newer 32-bit 
> > distro kernels because it *upgraded glibc*.
> 
> and what happened to those apps that users statically linked against
> the older glibc? what happened to their chroots that had dynamically
> linked binaries with an older glibc? did you not break those either?

There's two reasons why a distributor will generally not worry about 
that case:

 - No such binaries come with a default distro install

 - Keeping such old libraries linked or chrooted can be a security
   hole in itself, so i dou guarantee something like this.

If another distribution considers this a serious enough issue it can 
keep the COMPAT_VDSO option enabled forever. Few (none?) did.

Thanks,

	Ingo