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Sender: Tejun Heo <htejun@gmail.com>
Date:   Tue, 22 Feb 2022 08:09:51 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Imran Khan <imran.f.khan@oracle.com>, gregkh@linuxfoundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v6 6/7] kernfs: Introduce hashed rw-sem to replace per-fs
 kernfs_rwsem.
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On Fri, Feb 18, 2022 at 03:25:31AM +0000, Al Viro wrote:
> There are very few sources of cross-directory moves in the entire system.
> One is cross-directory cgroup rename(2) (already serialized on per-fs basis
> on VFS level), another is device_move().  Which is uncommon (5 callers

FWIW, cgroup rename(2) doesn't allow changing the parent.

Thanks.

-- 
tejun