Re: linux kernel panic when ejecting ieee1394 ipod

Jens Axboe
2005-12-09T13:36:26Z

On Thu, Dec 08 2005, Patrick Mansfield wrote:
> On Thu, Dec 08, 2005 at 03:44:42AM +0100, Stefan Richter wrote:
>
> > What if you replace WRITE by READ in
> > drivers/scsi/scsi_ioctl.c::scsi_cmd_ioctl()::case CDROMEJECT ?
>
> You must mean block/scsi_ioctl.c? i.e.:
>
> diff -uprN -X /home/patman/dontdiff linux-2.6.15-rc5-git1/block/scsi_ioctl.c mod- linux-2.6.15-rc5-git1/block/scsi_ioctl.c
> --- /home/linux/views/linux-2.6.15-rc5-git1/block/scsi_ioctl.c 2005-12-03 22:51:54.000000000 -0800
> +++ linux-2.6.15-rc5-git1/block/scsi_ioctl.c 2005-12-08 09:31:52.000000000 -0800
> @@ -566,7 +566,7 @@ int scsi_cmd_ioctl(struct file *file, st
> case CDROMCLOSETRAY:
> close = 1;
> case CDROMEJECT:
> - rq = blk_get_request(q, WRITE, __GFP_WAIT);
> + rq = blk_get_request(q, READ, __GFP_WAIT);
> rq->flags |= REQ_BLOCK_PC;
> rq->data = NULL;
> rq->data_len = 0;

This should not make a difference, the direction flag must be ignored
for !rq->data_len. Similarly you could translate the request with the
change above into DMA_FROM_DEVICE which is clearly false as well. So it
must be a bug somewhere that somebody only looks at the direction flag.

--
Jens Axboe