syzbot has bisected this issue to:
commit 2b0d3d3e4fcfb19d10f9a82910b8f0f05c56ee3e
Author: Ming Lei <ming.lei@xxxxxxxxxx>
Date: Thu Oct 1 15:48:41 2020 +0000
percpu_ref: reduce memory footprint of percpu_ref in fast path
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=126930d0500000
start commit: 8b787da7 Add linux-next specific files for 20201007
git tree: linux-next
final oops: https://syzkaller.appspot.com/x/report.txt?x=116930d0500000
console output: https://syzkaller.appspot.com/x/log.txt?x=166930d0500000
kernel config: https://syzkaller.appspot.com/x/.config?x=aac055e9c8fbd2b8
dashboard link: https://syzkaller.appspot.com/bug?extid=fd15ff734dace9e16437
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=119a0568500000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=106c0a8b900000
Reported-by: syzbot+fd15ff734dace9e16437@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 2b0d3d3e4fcf ("percpu_ref: reduce memory footprint of percpu_ref in fast path")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
