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Date:   Wed, 11 Oct 2023 02:26:51 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Amir Goldstein <amir73il@gmail.com>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        Christian Brauner <brauner@kernel.org>,
        Paul Moore <paul@paul-moore.com>,
        James Morris <jmorris@namei.org>,
        "Serge E . Hallyn" <serge@hallyn.com>,
        Mimi Zohar <zohar@linux.ibm.com>,
        linux-security-module@vger.kernel.org,
        linux-integrity@vger.kernel.org, linux-unionfs@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v3 3/3] fs: store real path instead of fake path in
 backing file f_path
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On Tue, Oct 10, 2023 at 09:28:41PM +0300, Amir Goldstein wrote:
> > with making vm_user_file() do this:
> >         file = vma->vm_file;
> >         if (file && unlikely(file->f_mode & FMODE_BACKING))
> >                 file = backing_file(file)->user_file;
> >         return file;
> >
> > Voila.  Two-commit series, considerably smaller than your
> > variant...
> >
> 
> Yap. looks very nice.
> I will try that out tomorrow.
> 
> Anyway, it doesn't hurt to have the current version in linux-next
> for the night to see if the change from fake f_path to real f_path
> has any unexpected outcomes.

There is an obvious problem with that approach - refcounts don't
mix with loops ;-/  Sorry about the noise - this really won't work.