ATA bus/drives order?

["FUKAUMI Naoki" <fun%naobsd.org@localhost>]

Hi,

NetBSD/xen is running on my machine now. (Thank you Christian!)

But I need to change BIOS setting. My machine has two parallel ATA and
two serial ATA interfaces. Serial ATA has two modes, one is compatible
mode and other is native mode.

If in native mode, ATA bus order is

  1. Parallel ATA Primary Master
  2. Parallel ATA Primary Slave
  3. Parallel ATA Secondary Master (DVD-ROM)
  4. Parallel ATA Secondary Slave
  5. Serial ATA 1st channel (HDD)
  6. Serial ATA 2nd channel

I have one HDD on 3rd bus and one DVD-ROM drive on 5th bus. In this case
DVD-ROM is attached first and HDD is attached next.
On NetBSD/xen kernel boot stage, cd and wd attach order is same as above.

In this case, it happens critical problem,

kernel built at 1 week ago:
  Kernel panic() on wd0 attach stage.

Today's kernel:
  Kernel boot normally, but mounting file systems with read-write mode
  (i.e. booting multi-user mode) causes kernel freeze.

I changed Serial ATA mode from native to compatible in BIOS. ATA bus
order is

  1. Parallel ATA Primary Master (incl S-ATA 1st chan.)
  2. Parallel ATA Primary Slave
  3. Parallel ATA Secondary Master (incl S-ATA 2nd chan.)
  4. Parallel ATA Secondary Slave

So HDD is attached first and DVD-ROM is 2nd now. In this case, no freeze,
no panic.

I don't know what is wrong, S-ATA native mode?, wd/cd attach order?,
Xen itself?, NetBSD/xen kernel or bootloader?

Any solution?

Regards,

--
FUKAUMI Naoki