From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Kent <raven@themaw.net>
Subject: Re: compat: autofs v5 packet size ambiguity - update
Date: Thu, 23 Feb 2012 09:35:02 +0800
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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, David Miller <davem@davemloft.net>, linux-kernel@vger.kernel.org, autofs@vger.kernel.org, Thomas Meyer <thomas@m3y3r.de>, Al Viro <viro@zeniv.linux.org.uk>

On Wed, 2012-02-22 at 07:13 -0800, H. Peter Anvin wrote:
> On 02/22/2012 01:32 AM, Ian Kent wrote:
> > 
> > Oh, DOH ... 
> > 
> > The process mounting the autofs mount is passing the pipe it will use
> > for communication via a mount option so we can do this right in
> > fill_super.
> > 
> 
> Does that mean that the autofs v5 daemon calls mount() by itself, unlike
> the older autofs daemon?  Otherwise you're reading the compatness of
> /bin/mount...

Version 5 does, yes.

There was nothing to be gained by the extra overhead of calling mount(8)
since I wanted to minimize mtab usage and contention, and didn't want
these showing up in mtab either.

> 
> 	-hpa
>