Re: Fix soft lockup with iSeries viocd driver

[Jens Axboe <jens.axboe@oracle.com>]

On Wed, Feb 28 2007, Tony Breeds wrote:
> On Tue, Feb 27, 2007 at 03:33:34PM +0100, Jens Axboe wrote:
> 
> > It looks ok (better than end_request()), though it would still be nice
> > to properly end requests. See the recent thread on the lguest block
> > driver.
> 
> Hi Jens,
> 	I read through the lguest thread and came up with the patch
> below, I hope I understood correctly.  We still need to do the check to
> make sure we ask for at least one sector to be processed in
> end_that_request_first(), as the request that triggers the lockup here
> (an sg_io ioctl in this case), has both req->hard_nr_sectors and
> req->hard_cur_sectors = 0.

Yep that looks better.

> From: Tony Breeds <tony@bakeyournoodle.com>
> 
> Fix soft lockup with iSeries viocd driver, caused by eventually calling
> end_that_request_first() with nr_bytes 0.
> 
> The lockup is triggered by hald, interrogating the device.
> 
> Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

-- 
Jens Axboe