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From: Andi Kleen <ak@suse.de>
Organization: SUSE Linux Products GmbH, Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg)
To: discuss@x86-64.org
Subject: Re: [discuss] [PATCH] Inconsistent mmap()/mremap() flags
Date: Tue, 2 Oct 2007 15:45:32 +0200
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Cc: Hugh Dickins <hugh@veritas.com>, Thayne Harbaugh <thayne@c2.net>,
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> First call mmap with a low hint address, the new size you'll be wanting
> from the mremap, PROT_NONE, MAP_ANONYMOUS, -1, 0.  Then call mremap with
> old address, old size, new size, MREMAP_MAYMOVE|MREMAP_FIXED, and new
> address as returned by the preparatory mmap.

That's racy unfortunately in a multithreaded process. They would need to loop.

-Andi