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Date: Sun, 16 Dec 2012 17:48:01 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Andy Lutomirski <luto@amacapital.net>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>, Michel Lespinasse <walken@google.com>,
        Hugh Dickins <hughd@google.com>, J??rn Engel <joern@logfs.org>
Subject: Re: [PATCH] mm: Downgrade mmap_sem before locking or populating on
 mmap
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On Sun, Dec 16, 2012 at 05:04:03PM +0000, Al Viro wrote:

> Moreover, I'm not quite convinced that huge_memory.c and ksm.c can't run
> into all kinds of interesting races with ongoing coredump.  Looking into
> it...

Specifically, is collapse_huge_page() safe in parallel with ->core_dump()?
It *can* run while we are in the middle of e.g. elf_core_dump().