Been tracking and resolving a bug in Linux's SPU scheduler for the last three days, and fixed it just a moment ago! I'm happy and needed to mention this ;-)
More specifically, tracking it down was fairly easy using SystemTap and Paraver (getting the two to play well together was another source of headaches), but fixing it was the most complex thing due to deadlocks popping up over and over again. Sorry, can't disclose more information about it yet; want to think a bit more how to make this public and whether my fix is really OK or not. But be sure I will!
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