Hi,

On Sat, May 08, 2004 at 11:44:30PM +0900, FUKAUMI Naoki wrote:
> 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.

You'd have to get the boot output from Xen and check if/how it detects
the IDE controllers and drives.  You'd probably have to attach a serial
console to see the output since it scrolls by too quickly (add
ser_baud=57600 to the xen-1.2.gz line in grub, only the 1st port is
supported).

> 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?

My guess is that S-ATA is not well/at all supported in Xen itself.  For the
guests it shouldn't make a difference since they only see virtual block
devices (scsi/ide, cd/dvd-rom, all look the same)

If you don't put the S-ATA controller in compatibility mode, does NetBSD
report the wd0's size correctly?

    christian