Re: Strange ATA problems

From: Robert Hancock
Date: Fri Dec 14 2007 - 20:50:09 EST


Tejun Heo wrote:
Dec 14 01:06:33 fermat kernel: ata1: EH in ADMA mode, notifier 0x0
notifier_error 0x0 gen_ctl 0x1501000 status 0x400 next cpb count 0x0
next
cpb idx 0x0
Dec 14 01:06:33 fermat kernel: ata1: CPB 0: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 1: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 2: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 3: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 4: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 5: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 6: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 7: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 8: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 9: ctl_flags 0x1f, resp_flags
0x2
Dec 14 01:06:33 fermat kernel: ata1: CPB 10: ctl_flags 0x1f, resp_flags
0x2

CPB flags stuck at 0x2 indicates that the controller issued the command to the drive and is waiting for completion. Usually seems to indicate some kind of SATA communication problem.

If your USB cdrom is bus powered and you yanked it, it could have caused
fluctuation in power which in turn can cause disruption on serial ATA
bus leading to transmission error and timeouts. There are other
possibilities but this kind of thing does happen often with SATA. Those
highspeed low-voltage serial links are very susceptible to interferences.
Well,.. it actually "worked" again when I unplugged it, but the errors
from the cdrom above are probably unrelated..


As long as EH recovered it properly, there's nothing to worry about.
What does that mean?

That means unless the problem continues to occur repeatedly, you don't
have to worry about it.


Yes, if it didn't recur, was likely just a transient glitch.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

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