On Mon, 29 Jan 2007, Mike Christie wrote: > > What chipsets are you guys using? I can see it with a 00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller (rev 02) 00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7 Family) Serial ATA Storage Controller IDE (rev 02) where the disk is on the SATA side, and the DVD writer is PATA using ide_piix. > I tried 2.6.20-rc6, and forced my cdrom to be used by the ide piix > driver instead of the sata one, so the device shows up as hda instead of > a scsi one. And, if I use the ide piix driver for the cdrom then it > works fine. I see IO going through the block layer sg io code which was > modified in 2.6.20 to support larger IOs. That doesn't sound very different from my setup.. I wonder why it works for you. That said, I'm making progress with my bisection. "16 revisions left to test after this", and three of those sixteen are Remove unnecessary blk_queue_bounce in SG_IO fix SG_IO bio leak remove blk_queue_activity_fn but I'll do the bisection 'til the bitter end, in case I get into a similar nonsense value that the other Mike got into. Linus - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html