From: Jens Axboe <axboe@kernel.dk>
To: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>, lkml <linux-kernel@vger.kernel.org>
Subject: Re: Bug at for-2.6.39/core
Date: Tue, 29 Mar 2011 11:50:20 +0200 [thread overview]
Message-ID: <4D91AB5C.8030203@kernel.dk> (raw)
In-Reply-To: <4D91AAB9.2000800@cn.fujitsu.com>
On 2011-03-29 11:47, Gui Jianfeng wrote:
> Hi Jens,
>
> I trigger an OOPS when testing, the following script can reproduce
> this bug on my box.
>
> #!/bin/sh
>
> mkdir /mnt/blkio
> mount -t cgroup -o blkio blkio /mnt/blkio/
> mkdir /mnt/blkio/test1 /mnt/blkio/test2
> echo noop > /sys/block/sdb/queue/scheduler
> dd iflag=direct if=/dev/sdb of=/dev/null bs=4k &
> echo $! > /mnt/blkio/test1/tasks
> dd iflag=direct if=/dev/sdb of=/dev/null bs=4k &
> echo $! > /mnt/blkio/test2/tasks
> sleep 3
> echo cfq > /sys/block/sdb/queue/scheduler
>
> ----
> eBUG: unable to handle kernel NULL pointer dereference at 0000000000000008
> IP: [<ffffffff812200e8>] cfq_completed_request+0x38/0x7f0
This is a known bug, update to Linus' current -git and it's fixed.
--
Jens Axboe
next prev parent reply other threads:[~2011-03-29 9:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-29 9:47 Bug at for-2.6.39/core Gui Jianfeng
2011-03-29 9:50 ` Jens Axboe [this message]
2011-03-30 1:12 ` Gui Jianfeng
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