https://bugzilla.kernel.org/show_bug.cgi?id=215447 --- Comment #6 from Martin K. Petersen (martin.petersen@xxxxxxxxxx) --- Christopher, > Is anyone able to comment on the sr_mod / cdrom / mptsas issue I'm > experiencing (see details in bug)? I fixed my issue with a one line > patch, but I'd like to know if it's correct and what I should do to > have it integrated upstream. My concern is that switching to MODE SENSE(10) by default could break things for other devices. There are compelling arguments that we should use MODE SENSE(10). Most ROM devices appear to favor it. The specs allow both but MMC3 (2001) mentions MODE SENSE(10) as "shall implement" although it doesn't go as far as marking it as mandatory in the SCSI command table. In the current code we fall back to the MODE SENSE(6) command if a MODE SENSE(10) fails. So if we change the default, unless a device hangs when we send the 10-byte command, we should be OK. Another option is to allow a fallback to the 10-byte command if the 6-byte command fails. We currently don't do that because MODE SENSE(6) was required for so many years. This way we could accommodate devices such as yours without the risk of changing the default. The good news is that the "consumer" transports (ATA, FireWire, USB) all use MODE SENSE(10) by default. So we are really only talking about changing things for SPI-attached devices which typically are well-behaved. So my hunch is that switching the default is probably OK, although I would like the 6/10-byte fallback mechanism to work in both directions as well. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
