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Date: Thu, 20 Dec 2012 10:40:59 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Roland McGrath <mcgrathr@google.com>
CC: "H.J. Lu" <hjl.tools@gmail.com>, Stefani Seibold <stefani@seibold.net>,
        Andy Lutomirski <luto@amacapital.net>, linux-kernel@vger.kernel.org,
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        xemul@parallels.com, gorcunov@openvz.org,
        andriy.shevchenko@linux.intel.com,
        Linus Torvalds <torvalds@linux-foundation.org>, jakub@redhat.com
Subject: Re: [PATCH 6/6] Add 32 bit VDSO support for 32 and 64 bit kernels
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On 12/20/2012 10:35 AM, Roland McGrath wrote:
> The Kconfig text for COMPAT_VDSO suggests that glibc versions prior to
> 2.3.3 may have relied on the fixed address.  I can't find anything in the
> libc revision history to explain that (AFAIK the code always used
> AT_SYSINFO* since it started using the vDSO at all), but it might have been
> something less obvious.  Someone like Jakub might recall the details.

Jakub, any insights?

We're trying to figure out if anything ever depended on the COMPAT_VDSO
(at a fixed address), in particular for i386 (as opposed to x86-64).

	-hpa