According to Manuel Bouyer:
>
>This loop should be correct, the tsleep shouldn't be awaked if the AT_DONE
>flag is not set. If this happens then there is a problem somewhere else.
>Note that wdc_exec_command() is not called very often in normal operations
>(only for a atactl I think).
>

Yes, I had another look at found that wdc_exec_command is not called
in many places at all :-(  I cannot see why the drive should be
wedging the machine at all.  I am starting to think that the drive
firmware has a bug that is crashing it just on the basis that the
drive shuts down totally when the machine hangs.  I am getting close
to going back to the 410 I had before at least the HD on that was
reliable and there was no weird blue flicker in X :-(

-- 
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Brett Lymn, Computer Systems Administrator, BAE SYSTEMS
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