From: David Howells <dhowells@redhat.com>
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To: Miklos Szeredi <mszeredi@redhat.com>
Cc: dhowells@redhat.com, Jeff Layton <jlayton@redhat.com>,
        viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        linux-nfs@vger.kernel.org, lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 3/9] VFS: Introduce a mount context
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Date: Wed, 10 May 2017 09:05:18 +0100
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Sender: linux-nfs-owner@vger.kernel.org

Miklos Szeredi <mszeredi@redhat.com> wrote:

> And the static string thing that David implemented is also a very good
> idea, IMO.

There is an issue with it: it's fine as long as you keep a ref on the module
that generated it or clear all strings as part of module removal (which the
mount context in this patchset does).  With the NFS mount context I did, I
have to keep a ref on the NFS protocol module as well as the NFS filesystem
module.

I'm tempted to make it conditionally copy the string using kvasprintf_const()
- which would also permit format substitution.

David