syzbot has bisected this bug to: commit b636fd38dc40113f853337a7d2a6885ad23b8811 Author: Tejun Heo <tj@xxxxxxxxxx> Date: Fri May 31 17:38:58 2019 +0000 cgroup: Implement css_task_iter_skip() bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1256fcd2a00000 start commit: 56b697c6 Add linux-next specific files for 20190604 git tree: linux-next final crash: https://syzkaller.appspot.com/x/report.txt?x=1156fcd2a00000 console output: https://syzkaller.appspot.com/x/log.txt?x=1656fcd2a00000 kernel config: https://syzkaller.appspot.com/x/.config?x=4248d6bc70076f7d dashboard link: https://syzkaller.appspot.com/bug?extid=9343b7623bc03dc680c1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=102ab292a00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15f0e27ca00000 Reported-by: syzbot+9343b7623bc03dc680c1@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: b636fd38dc40 ("cgroup: Implement css_task_iter_skip()") For information about bisection process see: https://goo.gl/tpsmEJ#bisection