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Date:   Thu, 14 Sep 2023 11:36:35 +0200
From:   Christian Brauner <brauner@kernel.org>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     Miklos Szeredi <mszeredi@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-api@vger.kernel.org, linux-man@vger.kernel.org,
        linux-security-module@vger.kernel.org, Karel Zak <kzak@redhat.com>,
        Ian Kent <raven@themaw.net>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Amir Goldstein <amir73il@gmail.com>
Subject: Re: [RFC PATCH 1/3] add unique mount ID
Message-ID: <20230914-jeweiligen-normung-47816c153531@brauner>
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> Yes, one concern is that humans confuse the old and the new ID.
> 
> I also think it makes sense to allow the new interfaces to look up the
> mount based on either the old or the new ID.   But I could be wrong

Hm, mount id recycling may happen so quickly that for service restarts
with a lot of mounts this becomes mostly useless...

> there, since that might encourage bad code.  Maybe the new interface
> should only use take the new ID, which means no mixed use of
> /proc/$$/mountinfo and statmnt/listmnt.

... so I think that is indeed the better way of doing things. There's no
need to encourage userspace to mix both identifiers.