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Date:   Sun, 8 Dec 2019 05:54:11 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     linux-fsdevel@vger.kernel.org
Subject: Re: [RFC PATCH] vfs: make rename_lock per-sb
Message-ID: <20191208055411.GT4203@ZenIV.linux.org.uk>
References: <20191128154858.GA16668@miu.piliscsaba.redhat.com>
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On Thu, Nov 28, 2019 at 04:48:58PM +0100, Miklos Szeredi wrote:

> Turning rename_lock into a per-sb lock mitigates the above issues.

... and completely fucks d_lookup(), since false negative can be
caused by rename of *ANYTHING* you've encountered while walking
a hash chain.

NAK.