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Date: Tue, 11 Mar 2014 10:03:03 -0700
From: "H. Peter Anvin" <hpa@linux.intel.com>
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To: Andy Lutomirski <luto@amacapital.net>
CC: Linus Torvalds <torvalds@linux-foundation.org>,
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        Stefani Seibold <stefani@seibold.net>,
        the arch/x86 maintainers <x86@kernel.org>,
        Dave Jones <davej@redhat.com>,
        Martin Runge <Martin.Runge@rohde-schwarz.com>,
        Andreas Brief <Andreas.Brief@rohde-schwarz.com>
Subject: Re: [PATCH v2] x86: Remove compat vdso support
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On 03/11/2014 09:45 AM, Andy Lutomirski wrote:
> 
> We could even just relocate the damn thing wherever it ends up.  That
> will waste one page of memory per process, though.
> 

We could definitely relocate it once and use the address across all
processes (e.g. top of the user address space.)

However, just changing one reserved page to two really is a trivial
change which preserves the status quo.

	-hpa