Re: INFO: task hung in lo_ioctl

[Tetsuo Handa]

On 2018/04/05 0:23, Tetsuo Handa wrote:
> This seems to be an AB-BA deadlock where the lockdep cannot report (due to use of nested lock?).
> What is happening here?
> 

This patch does not directly fix the bug syzbot is reporting, but could be relevant.
Maybe try replacing mutex_lock_killable_nested() with mutex_lock_killable() and
check what the lockdep will say?