From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH v2] vfs: Don't exchange "short" filenames unconditionally.
Date: Sat, 27 Sep 2014 12:37:36 -0700
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Cc: Mikhail Efremov <sem@altlinux.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Miklos Szeredi <mszeredi@suse.cz>,
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To: Al Viro <viro@zeniv.linux.org.uk>
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On Sat, Sep 27, 2014 at 12:16 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> FWIW, I suspect that the right approach is to put refcount + rcu_head in
> front of external name and do the following:

That's actually fancier than I was expecting. I was just thinking
doing a whole new allocation and freeing the old one using RCU. But I
guess you're right, you do need the rcu_head even for that, and once
you start adding fields you might as well just add a refcount too, and
then you don't have the annoyance of a potential memory allocation in
that code.

So your approach is better and doesn't sound too painful at all.

But yeah, I guess we can/should do the trivial ugly thing for 3.17.
Send me a proper pull-request,

                  Linus