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Date:   Sun, 4 Oct 2020 15:17:45 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     kernel test robot <lkp@intel.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Marc Zyngier <maz@kernel.org>, lkp@lists.01.org
Subject: Re: [ep_insert()] 9ee1cc5666:
 WARNING:possible_recursive_locking_detected
Message-ID: <20201004141745.GP3421308@ZenIV.linux.org.uk>
References: <20201004023929.2740074-20-viro@ZenIV.linux.org.uk>
 <20201004125619.GN393@shao2-debian>
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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.