[PATCH 00/12] perf: more fixes

[Peter Zijlstra]

About half of these patches are syz-kaller inspired, the rest is reported
fallout from the last round of fixes.

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).
But stability is otherwise greatly improved.

Please all, have a good hard look at these patches.

Thanks to Alexander for really spending some time with them.