Problem with SCSI sr_mod/st modules in 1.3.6

Aidan Dixon (
Thu, 6 Jul 1995 12:29:15 +0100 (BST)

In kernel digest #105, someone (Joachim Schmitz I think) mentioned the
problem of kernel panics when trying to access a device supposedly
enabled by adding a scsi tape module. I also have this problem with CD Roms.

Attempt to allocate device channel 0, target 6, lun 0
kernel panic: no device found in allocate_device()

I'm not sure exactly what the problem is and so don't have a fix, but to
me it seems to be related to the fact the unless a specific SCSI device
type is enabled via the config mechanism it won't be properly detected
when drivers/scsi/scsi.c:scan_scsis() is called during the kernel boot.

The usual vendor, type and revision number details are still printed out
(see drivers/scsi/scsi.c:print_inquiry()) but the final line of the
per-device recognition info. "Detected SCSI CDROM srN at scsiN, channel N
etc.." doesn't occur because the code to do this (in
drivers/scsi/sr.c:sr_detect()) isn't in the kernel at that point in time.
Consequently, no CDROMs are mentioned in the final scsi report line "SCSI
detected : N disks etc.." (in drivers/scsi/scsi.c:scsi_dev_init())
(Seems also like the device *is* actually register in the list created in
scan_scsis() but for some reason doesn't qualify for use!?)

'Fraid I don't know any more at this stage.


Aidan Thomas Dixon Prism Technologies Ltd.
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