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From: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Al Viro <viro@zeniv.linux.org.uk>,
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       <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH 6/6] vfs: introduce FMODE_NEG_OFFSET for allowing negative f_pos
References: <20100115013954.311049665@intel.com>
	<20100115014422.959401729@intel.com>
	<87bpgurz00.fsf@devron.myhome.or.jp>
	<20100118091527.7a0e2c6e.kamezawa.hiroyu@jp.fujitsu.com>
	<87y6jwnrcz.fsf@devron.myhome.or.jp>
	<873a24mc3i.fsf@devron.myhome.or.jp>
	<20100118104913.66c8d90c.kamezawa.hiroyu@jp.fujitsu.com>
Date: Mon, 18 Jan 2010 10:59:10 +0900
In-Reply-To: <20100118104913.66c8d90c.kamezawa.hiroyu@jp.fujitsu.com>
	(KAMEZAWA Hiroyuki's message of "Mon, 18 Jan 2010 10:49:13 +0900")
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KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> writes:

>> BTW, another concern by negative "pos" value is, the following like code
>> 
>> 	pos >> shift_bits
>> 
>> it will break the above. So, I think it should be checked if not yet.
>
> Where do we check ?
>
> FMODE_NEG_OFFSET is just used by /dev/mem and /proc/<pid>/mem. And I don't
> think there are no additonal users. So, I myself don't have has such concerns...

Sorry, it's just my concern. I'm not checking real path (e.g. vfs) of
related to /dev/mem, if there is no user of such code, it's ok.

Thanks.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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