syzbot has bisected this bug to: commit 1cf8dfe8a661f0462925df943140e9f6d1ea5233 Author: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Date: Sat Jul 13 09:21:25 2019 +0000 perf/core: Fix race between close() and fork() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1523f40c600000 start commit: c6dd78fc Merge branch 'x86-urgent-for-linus' of git://git... git tree: upstream final crash: https://syzkaller.appspot.com/x/report.txt?x=1723f40c600000 console output: https://syzkaller.appspot.com/x/log.txt?x=1323f40c600000 kernel config: https://syzkaller.appspot.com/x/.config?x=7937b718ddac333b dashboard link: https://syzkaller.appspot.com/bug?extid=7692cea7450c97fa2a0a syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17e888cc600000 Reported-by: syzbot+7692cea7450c97fa2a0a@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 1cf8dfe8a661 ("perf/core: Fix race between close() and fork()") For information about bisection process see: https://goo.gl/tpsmEJ#bisection