Re: KASAN: use-after-free Write in __vb2_cleanup_fileio

syzbot has bisected this bug to:

commit 4493b81bea24269df898339dee638d7c5cb2b2df
Author: Mahesh Bandewar [off-list ref]
Date:   Wed Mar 8 18:55:54 2017 +0000

     bonding: initialize work-queues during creation of bond

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=1232b037200000
start commit:   4493b81b bonding: initialize work-queues during creation o..
git tree:       upstream
final crash:    https://syzkaller.appspot.com/x/report.txt?x=1132b037200000
console output: https://syzkaller.appspot.com/x/log.txt?x=1632b037200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=62118286bb772a24
dashboard link: https://syzkaller.appspot.com/bug?extid=4e12d2d56f8ccc65c180
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1346e183400000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=117c2713400000

Reported-by: syzbot+4e12d2d56f8ccc65c180@syzkaller.appspotmail.com
Fixes: 4493b81bea24 ("bonding: initialize work-queues during creation of  
bond")

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