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Date: Wed, 24 Nov 2004 22:18:00 +0100
From: Jens Axboe <axboe@suse.de>
To: Maneesh Soni <maneesh@in.ibm.com>
Cc: "Christopher S. Aker" <caker@theshore.net>, linux-kernel@vger.kernel.org,
       Greg KH <greg@kroah.com>
Subject: Re: 2.6.10-rc2-bk7 - kernel BUG at fs/sysfs/file.c:87!
Message-ID: <20041124211800.GQ13847@suse.de>
References: <002c01c4d25b$3e8b9b10$0201a8c0@hawk> <20041124204138.GA2543@in.ibm.com>
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On Wed, Nov 24 2004, Maneesh Soni wrote:
> On Wed, Nov 24, 2004 at 07:26:43PM +0000, Christopher S. Aker wrote:
> > Doing "cat /sys/block/sda/queue/iosched/show_status" produces the following BUG:
> > 
> > ------------[ cut here ]------------
> > kernel BUG at fs/sysfs/file.c:87!
> 
> I think you are using cfq io scheduler. show_status is from cfq_ioched. Looks 
> like return value freom cfq_status_show() is going beyond one page. 
> read/write buffer for sysfs text attribute files is limited to one page. 

Yeah, with many processes that is easy to hit. I dunno how to fix it
yet, is it possible to combine sysfs with the seq stuff? The file should
just be deleted, though.

-- 
Jens Axboe