I don't get gow notes work WRT up->nerrlab.
say we schedule an alarm() call, and then go to sleep.
the note will fire when the alarm expires and cause
the processes notify function to be called.
this notify function calls noted() and in doing so sets
up->nerrlab to zero. assuming noted was called with NCONT
the alarm function will be made ready and will return, doing
poperror as it goes.
I would expect this to give an error of the form:
bad errstack [%lud]: %d extra
clearly this doesn't happen so there is some magic I don't
understand going on here, but what is it?
Thanks all.
-Steve
