NetBSD-2.0RC4 and current (20041015). asus p4s800d with latest v1011 
bios. The first PATA chains appear good, but the SATA chain gets "lost 
interrupt". The dmesg is attached.

I have been searching archives, and someone suggested perhaps they could 
not do UDMA at 512 sized blocks, so I forced PIO mode (flags 0x0ffc) but 
that made no difference. Attempted to join the drives as a raid, and 
have the unit see the raid instead of wd4 and wd5. No difference. 
Nothing else is on irq 11.

Also tried disabling anything we don't need, USB and that. Someone else 
had success turning on debug prints, but that made no difference to us.

Without those two drives plugged in it works great. Even with MP build.

siside.c latest we've tried is v1.13

dmesg:
(damn by the time it boots and lets me login, most of the dmesg is gone, 
including /var/run/dmesg.boot)


GENERIC.MP (as much as I can get)

PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR>
cpu0: features bfebfbff<PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX>
cpu0: features bfebfbff<FXSR,SSE,SSE2,SS,HTT,TM,SBF>
cpu0: I-cache 12K uOp cache 8-way
cpu0: L2 cache 1 MB 64B/line 8-way
cpu0: ITLB 4K/4M: 64 entries
cpu0: DTLB 4K/4M: 64 entries
cpu0: calibrating local timer
cpu0: apic clock running at 200 MHz
cpu0: 32 page colors
cpu1 at mainbus0: apid 1 (application processor)
cpu1: starting
cpu1: Intel (686-class), 2800.80 MHz, id 0xf33
cpu1: features bfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR>
cpu1: features bfebfbff<PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX>
cpu1: features bfebfbff<FXSR,SSE,SSE2,SS,HTT,TM,SBF>
cpu1: I-cache 12K uOp cache 8-way
cpu1: L2 cache 1 MB 64B/line 8-way
cpu1: ITLB 4K/4M: 64 entries
cpu1: DTLB 4K/4M: 64 entries
ioapic0 at mainbus0 apid 2 (I/O APIC)
ioapic0: pa 0xfec00000, version 11, 24 pins
ioapic0: misconfigured as apic 0
ioapic0: remapped to apic 2
acpi0 at mainbus0
acpi0: using Intel ACPI CA subsystem version 20040211
acpi0: X/RSDT: OemId <A M I ,OEMXSDT ,09000417>, AslId <MSFT,00000097>
acpi0: SCI interrupting at int 9
acpi0: fixed-feature power button present
ACPI Object Type 'Processor' (0x0c) at acpi0 not configured
ACPI Object Type 'Processor' (0x0c) at acpi0 not configured
PNP0A03 at acpi0 not configured
PNP0000 at acpi0 not configured
PNP0200 at acpi0 not configured
PNP0100 at acpi0 not configured
PNP0B00 at acpi0 not configured
PNP0303 at acpi0 not configured
PNP0800 at acpi0 not configured
PNP0C04 at acpi0 not configured
PNP0700 at acpi0 not configured
PNP0C02 at acpi0 not configured
PNP0C02 at acpi0 not configured
PNP0C02 at acpi0 not configured
PNP0C01 at acpi0 not configured
PNP0C0C at acpi0 not configured
PNP0C0F at acpi0 not configured
PNP0C0F at acpi0 not configured
PNP0C0F at acpi0 not configured
pci0 at mainbus0 bus 0: configuration mode 1
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
pchb0 at pci0 dev 0 function 0
pchb0: Silicon Integrated System SiS 655 Host Bridge (rev. 0x50)
agp0 at pchb0: aperture at 0xf8000000, size 0x4000000
ppb0 at pci0 dev 1 function 0: Silicon Integrated System product 0x0003 
(rev. 0x
00)
pci1 at ppb0 bus 1
pci1: memory space enabled
pcib0 at pci0 dev 2 function 0
pcib0: Silicon Integrated System 964 Host Bridge (rev. 0x36)
siside0 at pci0 dev 2 function 5
siside0: Silicon Integrated Systems 96X UDMA6655 IDE controller (rev. 0x01)
siside0: bus-master DMA support present
siside0: primary channel configured to compatibility mode
siside0: primary channel interrupting at ioapic0 pin 14 (irq 14)
atabus0 at siside0 channel 0
siside0: secondary channel configured to compatibility mode
siside0: secondary channel interrupting at ioapic0 pin 15 (irq 15)
atabus1 at siside0 channel 1
sip0 at pci0 dev 4 function 0: SiS 900 10/100 Ethernet, rev 0x91
sip0: interrupting at ioapic0 pin 19 (irq 5)
sip0: Ethernet address 00:11:2f:30:44:b6
ukphy0 at sip0 phy 1: Generic IEEE 802.3u media interface
ukphy0: OUI 0x000004, model 0x0020, rev. 1
ukphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
siside1 at pci0 dev 5 function 0
siside1: Silicon Integrated Systems 180/96X SATA controller (rev. 0x01)

siside1: primary channel wired to native-PCI mode
siside1: using ioapic0 pin 17 (irq 10) for native-PCI interrupt
atabus2 at siside1 channel 0
siside1: secondary channel wired to native-PCI mode
atabus3 at siside1 channel 1
pdcide0 at pci0 dev 8 function 0
pdcide0: Promise Ultra133/ATA Bus Master IDE Accelerator (rev. 0x02)
pdcide0: bus-master DMA support present
pdcide0: primary channel configured to native-PCI mode
pdcide0: using ioapic0 pin 16 (irq 3) for native-PCI interrupt
atabus4 at pdcide0 channel 0
pdcide0: secondary channel configured to native-PCI mode
atabus5 at pdcide0 channel 1
vga1 at pci0 dev 10 function 0: ATI Technologies Mach64 VT (rev. 0x40)
wsdisplay0 at vga1 kbdmux 1: console (80x25, vt100 emulation)
wsmux1: connecting to wsdisplay0
isa0 at pcib0
pckbc0 at isa0 port 0x60-0x64
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pcppi0 at isa0 port 0x61
sysbeep0 at pcppi0
isapnp0 at isa0 port 0x279: ISA Plug 'n Play device support
npx0 at isa0 port 0xf0-0xff: using exception 16
isapnp0: no ISA Plug 'n Play devices found
ioapic0: enabling
wd0 at atabus0 drive 0: <ST310211A>
wd0: drive supports 16-sector PIO transfers, LBA addressing
wd0: 9541 MB, 19386 cyl, 16 head, 63 sec, 512 bytes/sect x 19541088 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 (Ultra/100)
wd1 at atabus0 drive 1: <Maxtor 4G120J6>
wd1: drive supports 16-sector PIO transfers, LBA48 addressing
wd1: 114 GB, 238216 cyl, 16 head, 63 sec, 512 bytes/sect x 240121728 sectors
wd1: 32-bit data port
wd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd0(siside0:0:0): using PIO mode 4, Ultra-DMA mode 5 (Ultra/100) (using 
DMA data
  transfers)
wd1(siside0:0:1): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using 
DMA data
  transfers)
wd2 at atabus1 drive 0: <Maxtor 4D080H4>
wd2: drive supports 16-sector PIO transfers, LBA48 addressing
wd2: 78167 MB, 158816 cyl, 16 head, 63 sec, 512 bytes/sect x 160086528 
sectors
wd2: 32-bit data port
wd2: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd3 at atabus1 drive 1: <Maxtor 6Y160P0>
wd3: drive supports 16-sector PIO transfers, LBA48 addressing
wd3: 152 GB, 317632 cyl, 16 head, 63 sec, 512 bytes/sect x 320173056 sectors
wd3: 32-bit data port
wd3: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd2(siside0:1:0): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using 
DMA data
  transfers)
wd3(siside0:1:1): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using 
DMA data
  transfers)
wd4 at atabus2 drive 0siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
: <Maxtor 6B200M0>
wd4: drive supports 16-sector PIO transfers, LBA48 addressing
wd4: 189 GB, 395136 cyl, 16 head, 63 sec, 512 bytes/sect x 398297088 sectors
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4: 32-bit data port
siside1:0:0: lost interrupt
         type: ata tc_bcount: 0 tc_skip: 0
wd4: drive supports PIO mode 4siside1:0:0: lost interrupt
         type: ata tc_bcount: 0 tc_skip: 0
, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd4(siside1:0:0): using PIO mode 4
wd5 at atabus3 drive 0siside1:1:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
: <Maxtor 6B200M0>
wd5: drive supports 16-sector PIO transfers, LBA48 addressing
wd5: 189 GB, 395136 cyl, 16 head, 63 sec, 512 bytes/sect x 398297088 sectors
siside1:1:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
siside1:1:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd5: 32-bit data port
siside1:1:0: lost interrupt
         type: ata tc_bcount: 0 tc_skip: 0
wd5: drive supports PIO mode 4siside1:1:0: lost interrupt
         type: ata tc_bcount: 0 tc_skip: 0
, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd5(siside1:1:0): using PIO mode 4
wd6 at atabus4 drive 0: <Maxtor 4G120J6>
wd6: drive supports 16-sector PIO transfers, LBA48 addressing
wd6: 114 GB, 238216 cyl, 16 head, 63 sec, 512 bytes/sect x 240121728 sectors
wd6: 32-bit data port
wd6: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd6(pdcide0:0:0): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using 
DMA data
  transfers)
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0)
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0), retrying
siside1:0:0: lost interrupt
         type: ata tc_bcount: 512 tc_skip: 0
wd4d: device timeout reading fsbn 0 (wd4 bn 0; cn 0 tn 0 sn 0)
wd4: dos partition I/O error
[snip snip]
wd5d: device timeout reading fsbn 0 of 0-3 (wd5 bn 0; cn 0 tn 0 sn 0), 
retrying
siside1:1:0: lost interrupt
         type: ata tc_bcount: 2048 tc_skip: 0
wd5d: device timeout reading fsbn 0 of 0-3 (wd5 bn 0; cn 0 tn 0 sn 0)
boot device: wd0
root on wd0a dumps on wd0b
root file system type: ffs
cpu1: CPU 1 running
wsdisplay0: screen 1 added (80x25, vt100 emulation)
wsdisplay0: screen 2 added (80x25, vt100 emulation)
wsdisplay0: screen 3 added (80x25, vt100 emulation)
wsdisplay0: screen 4 added (80x25, vt100 emulation)