Re: [PATCH] Initialise scatter/gather list in ata_sg_setup

Jens Axboe
2007-10-26T12:01:05Z

On Thu, Oct 25 2007, Anton Blanchard wrote:
>
> (Sorry the subject was incorrect)...
>
> After turning on DEBUG_SG I hit a fail:
>
> kernel BUG at include/linux/scatterlist.h:50!
>
> ata_qc_issue
> ata_scsi_translate
> ipr_queuecommand
> scsi_dispatch_cmd
> scsi_request_fn
> elv_insert
> blk_execute_rq_nowait
> blk_execute_rq
> sg_io
> scsi_cmd_ioctl
> cdrom_ioctl
> sr_block_ioctl
> blkdev_driver_ioctl
> blkdev_ioctl
> block_ioctl
> do_ioctl
> vfs_ioctl
> sys_ioctl
> sg_ioctl_trans
>
> It looks like ata_sg_setup is working on an uninitialised sg table. Call
> sg_init_table to initialise it before use.
>
> Signed-off-by: Anton Blanchard <anton@samba.org>
> ---
>
> Jens this is against your sg branch. This fixes the fail but Id
> appreciate a confirmation that it's the right fix :)

The patch looks OK, you could also get away with just doing that
sg_init_table() on qc init/alloc.

--
Jens Axboe