Re: INFO: task hung in synchronize_rcu (3)

syzbot has bisected this issue to:

commit 5a781ccbd19e4664babcbe4b4ead7aa2b9283d22
Author: Vinicius Costa Gomes [off-list ref]
Date:   Sat Sep 29 00:59:43 2018 +0000

    tc: Add support for configuring the taprio scheduler

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=149057ef100000
start commit:   4fa640dc Merge tag 'vfio-v5.8-rc7' of git://github.com/awi..
git tree:       upstream
final oops:     https://syzkaller.appspot.com/x/report.txt?x=169057ef100000
console output: https://syzkaller.appspot.com/x/log.txt?x=129057ef100000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f87a5e4232fdb267
dashboard link: https://syzkaller.appspot.com/bug?extid=0c6da80218456f1edc36
userspace arch: i386
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14e2a437100000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13af00e8900000

Reported-by: syzbot+0c6da80218456f1edc36@syzkaller.appspotmail.com
Fixes: 5a781ccbd19e ("tc: Add support for configuring the taprio scheduler")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection