Hi,

I have successfully installed NetBSD 1.5.2 on a Dell PowerEdge 1500SC using
the AIC-7899 patch on pchb.c backported by Johnny Lam from current (see
archives).

I also successfully configured RAIDFrame in RAID1 using my 2x 18GB U160
drives in their hot pluggable bays.

To prepare for the worst and test my RAIDFrame setup I tried pulling one of
the drives while the system was running and, to my surprise, the SCSI driver
panic'ed the machine.

Here's the trace of what happened once I pulled the drive:

    ahc1: AHC_INTR - referenced SCB not valid during SELTO SCP(14,26)
    ... (a bunch of these)

    sd0 (ahc1:0:0) SCB 1c : timed out while idle, SEQ ADDR == 0x43
    SCSI RATE == 0x0
    sd0 (ahc1:0:0) SCB 1c : internal reset. Flags = 0x4040
    sd0 (ahc1:0:0) SCB 1c : no longer in timeout, status = 0
    panic: biodone already

Now, after rebooting, everything was as expected, the drive was failed in
RAIDFrame and I was able to rebuild it as I should.

Is this a problem specific to the AIC-7899 driver or is it a "weakness" in
the SCSI code in relation to RAIDFrame? In all cases do we know if we can
expect an improvement in that area?

Thanks,
Colin.