Re: [ep_insert()] 9ee1cc5666: WARNING:possible_recursive_locking_detected

From: Al Viro
Date: Sun Oct 04 2020 - 10:17:52 EST


On Sun, Oct 04, 2020 at 08:56:19PM +0800, kernel test robot wrote:
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: 9ee1cc56661640a2ace2f7d0b52dec56b3573c53 ("[RFC PATCH 20/27] ep_insert(): we only need tep->mtx around the insertion itself")
> url: https://github.com/0day-ci/linux/commits/Al-Viro/epoll-switch-epitem-pwqlist-to-single-linked-list/20201004-113938
> base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git 22fbc037cd32e4e6771d2271b565806cfb8c134c

False positive, actually - that should've been mutex_lock_nested()
with 1 for depth; will update.