Freezes on sata_uli hd

[TommyDrum]

Hello everyone!

I've got this problem from a while, and maybe this time I've nailed a portion 
of it; here goes:

I'm running Gentoo Linux, latest stable gentoo-sources (2.6.20-r8). I'm having 
random freezes of the system, including no mouse or keyboard interaction 
(SysRq not working), all accompanied by a stable-on HD activity led; HD seems 
not to work though, and X activity remains frozen; the only alternative is to 
hard reset.
Changed memory timing in bios, swapped memory, changed SMART, changed sata 
cables and ports; no avail.

/var/log/messages shows no unusual activity, so there's not an oops or other 
significant message before freezing.

This last time the system froze only for the libata part, leaving me keyboard 
mouse X and other HD activity stable; dmesg showed the following:

ata1: SATA max UDMA/133 cmd 0xFFFFC20000020100 ctl 0x0 bmdma 0x0 irq 35
ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata1.00: ATA-7, max UDMA/133, 488397168 sectors: LBA48 NCQ (depth 31/32)
ata1.00: ata1: dev 0 multi count 16
ata1.00: configured for UDMA/133
sata_uli 0000:00:12.1: version 1.0
ata2: SATA max UDMA/133 cmd 0xEC00 ctl 0xE082 bmdma 0xD880 irq 19
ata3: SATA max UDMA/133 cmd 0xE000 ctl 0xDC02 bmdma 0xD888 irq 19
scsi1 : sata_uli
ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata2.00: ATA-7, max UDMA/133, 586114704 sectors: LBA48 NCQ (depth 0/32)
ata2.00: ata2: dev 0 multi count 16
ata2.00: configured for UDMA/133
scsi2 : sata_uli

<snip>

ata2.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2 frozen
ata2.00: cmd c8/00:40:0b:3a:e9/00:00:00:00:00/e6 tag 0 cdb 0x0 data 32768 in
         res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata2: port is slow to respond, please be patient (Status 0xd0)
ata2: port failed to respond (30 secs, Status 0xd0)
ata2: soft resetting port
ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata2.00: configured for UDMA/133
ata2: EH complete
SCSI device sdb: 586114704 512-byte hdwr sectors (300091 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: write cache: enabled, read cache: enabled, doesn't support 
DPO or FUA

I noticed NCQ is not enabled on that device, and trying to echo 31 to 
queue_depth initially gives permission denied; chmod root to rw, then echo 31 
to queue_depth gives input/output error.

I don't know if this is relevant to the total freezes, and haven't been able 
to find correspondence between ata devices and /dev/sdx ; if I can give you 
any more info, I'll be glad to.

Meanwhile:
lspci -v to the relevant devices:

00:12.1 IDE interface: ALi Corporation ULi 5289 SATA (rev 10) (prog-if 8f 
[Master SecP SecO PriP PriO])
        Subsystem: ASRock Incorporation Unknown device 5289
        Flags: bus master, 66MHz, medium devsel, latency 32, IRQ 19
        I/O ports at ec00 [size=8]
        I/O ports at e080 [size=4]
        I/O ports at e000 [size=8]
        I/O ports at dc00 [size=4]
        I/O ports at d880 [size=16]

Thanks in advance,
tommy

Attachment: signature.asc
Description: This is a digitally signed message part.