From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Axboe <axboe@kernel.dk>
Subject: Re: kernel BUG at drivers/block/virtio_blk.c:172!
Date: Mon, 10 Nov 2014 16:31:51 -0700
Message-ID: <54614AE7.2080204@kernel.dk>
References: <20141107080416.0837a88c@tlielax.poochiereds.net>
	<87bnofnzop.fsf@rustcorp.com.au>
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To: Rusty Russell <rusty@rustcorp.com.au>, Jeff Layton <jlayton@poochiereds.net>, "Michael S. Tsirkin" <mst@redhat.com>, Dave Chinner <david@fromorbit.com>
Cc: Ming Lei <tom.leiming@gmail.com>, xfs@oss.sgi.com, virtualization@lists.linux-foundation.org
List-Id: virtualization@lists.linuxfoundation.org

On 2014-11-10 02:59, Rusty Russell wrote:
> Jeff Layton <jlayton@poochiereds.net> writes:
>
>> In the latest Fedora rawhide kernel in the repos, I'm seeing the
>> following oops when mounting xfs. rc2-ish kernels seem to be fine:
>>
>> [   64.669633] ------------[ cut here ]------------
>> [   64.670008] kernel BUG at drivers/block/virtio_blk.c:172!
>
> Hmm, that's:
>
> 	BUG_ON(req->nr_phys_segments + 2 > vblk->sg_elems);
>
> But during our probe routine we said:
>
> 	/* We can handle whatever the host told us to handle. */
> 	blk_queue_max_segments(q, vblk->sg_elems-2);
>
> Jens?

Known, I'm afraid, Ming is looking into it.

-- 
Jens Axboe