Re: Spurious completions during NCQ

[Mark Lord <liml@rtr.ca>]

Hugo Mills wrote:
>    I'm getting these on my Dell Latitude D830:
> 
> Feb 15 13:06:00 willow kernel: ata1.00: exception Emask 0x2 SAct 0x4 SErr 0x0 action 0x2 frozen
> Feb 15 13:06:00 willow kernel: ata1.00: spurious completions during NCQ issue=0x0 SAct=0x4 FIS=004040a1:00000002
> Feb 15 13:06:00 willow kernel: ata1.00: cmd 61/10:10:26:fb:c4/00:00:02:00:00/40 tag 2 cdb 0x0 data 8192 out
> Feb 15 13:06:00 willow kernel:          res 40/00:10:26:fb:c4/00:00:02:00:00/40 Emask 0x2 (HSM violation)
> Feb 15 13:06:00 willow kernel: ata1: soft resetting port
> Feb 15 13:06:00 willow kernel: ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
> Feb 15 13:06:00 willow kernel: ata1.00: configured for UDMA/133
> Feb 15 13:06:00 willow kernel: ata1: EH complete
> Feb 15 13:06:00 willow kernel: sd 0:0:0:0: [sda] 312581808 512-byte hardware sectors (160042 MB)
> Feb 15 13:06:00 willow kernel: sd 0:0:0:0: [sda] Write Protect is off
> Feb 15 13:06:00 willow kernel: sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
> Feb 15 13:06:00 willow kernel: sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
> 
>    In some cases, there are several cmd/res lines listed. It's
> happening about once an hour or so (not correlated with any other
> event that I can see). It doesn't seem to be affecting operation of
> the machine, but it's making me nervous.
> 
>    Can anyone set my mind at rest? (Or suggest a fix?)
..

Tejun, have the spurious completion fixes been backported
to 2.6.23 / 2.6.22 yet ?  Those kernels will be in common use
for some time to come, and this fix is more or less essential.

???