Let me guess... this is a T61 or X61 ?
There's a problem with these that we don't fully understand yet, we're
getting those stale interrupts all over the range.
I wonder if it could be a bug with the ICH8 chipset...
If yours is one of these, it's being dealt with (or attempted to deal
with) at
http://bugzilla.kernel.org/show_bug.cgi?id=8853
Ben.
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