ahd0 dumps when an ext. raid attached

[Scott Long]

Rong-en Fan wrote:
> We have an ahd0 on IBM x236 server:
> 
> ahd0: <Adaptec 29320LP Ultra320 SCSI adapter> port
> 0x4000-0x40ff,0x4100-0x41ff mem 0xcfffe000-0xcfffffff irq 25 at device
> 12.0 on pci3
> ahd0: [GIANT-LOCKED]
> aic7901A: Ultra320 Wide Channel A, SCSI Id=7, PCI-X 67-100Mhz, 512 SCBs
> 
> The server runs i386 6.2-RELEASE. There is a tape driver on this card. When
> I attach an external RAID (U160, scsi chip is LSI1020, I think), ahd0
> gets unhappy.
> It dumps when the kernel tries to probe the device.
> 
> The verbose boot log is at
> 
> http://www.rafan.org/tmp/ahd0.dump.txt
> 
> This RAID works fine if I attach it to a LSI card. But due to other
> reasons, I can
> not use LSI card on this server.
> 
> Suggestions are welcome.
> 
> Regards,
> Rong-En Fan

The chip is detecting many transmission errors.  Maybe you have a bad
cable?  Try using the BIOS to force all targets to U160 or lower.  You
should also try forcing packetized mode off from the BIOS.  If it's not
the cable then there is some sort of major incompatibility with the
firmware of that device.  Other OS's might be covering it up by
automatically doing domain validation and silently downshifting the
speed.

Scott