Peter Zijlstra <pet...@infradead.org> writes: > On Wed, Feb 24, 2016 at 06:45:39PM +0100, Peter Zijlstra wrote: > >> With these patches syz-kaller can still trigger some fail; most notably some >> NMI watchdog triggers and a very sporadic unthrottle bug (much like last >> time). > > So the below seems to make the sporadic unthrottle thing much less > likely in that I haven't seen it in several hours, my machine keeps > dying on NMI watchdog bits. > > Boris, who has been running syz-kaller on AMD hardware and was hitting a > very similar bug with the AMD-IBS code, says its not fixed it for him, > so maybe there's still more to find. > > --- > Subject: perf: Fix unthrottle > > Its possible to IOC_PERIOD while the event is throttled, this would > re-start the event and the next tick would then try to unthrottle it, > and find the event wasn't actually stopped anymore. > > This would tickle a WARN in the x86-pmu code which isn't expecting to > start a !stopped event. > > Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
FWIW, Reviewed-by: Alexander Shishkin <alexander.shish...@linux.intel.com> Cheers, -- Alex