Re: BUG in 2.5.50

[Jens Axboe]

On Mon, Dec 09 2002, Zwane Mwaikambo wrote:
> Added Jens to CC to verify any incorrect information i may or may not put
> down.
> 
> On Mon, 9 Dec 2002, Roy Sigurd Karlsbakk wrote:
> 
> > installed 2.5.50 and got an OOPS after a short while. .
> > config is attached as tonjeconfig
> > /var/log/messages including dmesg and oops is attached as tonje_messages
> 
> Perhaps this might help with debugging;
> 
> He has CONFIG_BLK_DEV_IDE_TCQ enabled and his IBM supports it,
> 
> when he gets to do_rw_disk();
> 
> We know its a READ request
> 	if (rq_data_dir(rq) == READ) {
> 		if (blk_rq_tagged(rq))
> 			return hwif->ide_dma_queued_read(drive);
> 
> ... the request isn't tagged so we drop down here...
> 
> 		if (drive->using_dma && !hwif->ide_dma_read(drive))
> 			return ide_started;
> 
> int __ide_dma_read (ide_drive_t *drive)
> ...
> 	if (HWGROUP(drive)->handler != NULL)
> 		BUG();
> 
> and ->handler = ?

If tcq is enabled on the drive, rq _must_ be tagged.

-- 
Jens Axboe