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Date: Fri, 05 Sep 2008 17:06:18 +0900
From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
To: Mel Gorman <mel@csn.ul.ie>
Subject: Re: [PATCH] coredump_filter: add hugepage core dumping
Cc: kosaki.motohiro@jp.fujitsu.com,
       Kawai Hidehiro <hidehiro.kawai.ez@hitachi.com>,
       Hugh Dickins <hugh@veritas.com>, William Irwin <wli@holomorphy.com>,
       Adam Litke <agl@us.ibm.com>, LKML <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>
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Hi

> That aside, it is not always safe to read a VM_RESERVED area without
> side-effects.
> 
> > This patch doesn't change dafault behavior.
> > 
> 
> I wonder about this and if that is the right thing to do. By default,
> core dumps include anonymous private and shared memory. Strictly speaking,
> hugetlbfs is a file-backed mapping but it is always a ram-based file and a
> private mapping is likely to contain information that would normally be in
> a private anonymous mapping. It feels like that information should be core
> dumped by default. Would it be better to
> 
> 1. Distinguish between private and shared hugetlbfs mappings
> 2. Default dump MAP_PRIVATE hugetlbfs mappings
> 
> ?

make much sense.
ok, I'll make again under your design.

Thank you very much.