Comment 6 for bug 163637

I hit this issue too,

ata1.00: exception Emask 0x2 SAct 0x4 SErr 0x0 action 0x2 frozen
ata1.00: (spurious completions during NCQ issue=0x0 SAct=0x4 FIS=004040a1:00000002)
ata1.00: cmd 61/08:10:a3:aa:49/00:00:07:00:00/40 tag 2 cdb 0x0 data 4096 out
         res 40/00:10:a3:aa:49/00:00:07:00:00/40 Emask 0x2 (HSM violation)
ata1: soft resetting port
ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata1.00: configured for UDMA/133
ata1: EH complete
sd 0:0:0:0: [sda] 312581808 512-byte hardware sectors (160042 MB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

its a known bug with the ahci driver and fixed in the following commit to 2.6.22-stable

http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.22.y.git;a=commit;h=2370eae7567e06b10f68ce293cb2a6b4f773b0c7

Applying this patch and recompiling the kernel fixed this issue for me

Model Family: Maxtor DiamondMax 10 family (SATA/300)
Firmware Version: VA111900

it doesn't apply cleanly because the Ubuntu developers have changed the blacklist already, but the driver part is okay.