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Date: Sun, 12 Aug 2007 21:23:20 +0100
From: Al Viro <viro@ftp.linux.org.uk>
To: Jan Engelhardt <jengelh@computergmbh.de>
Cc: Mark Cannon <random.bits@rogers.com>, "H. Peter Anvin" <hpa@zytor.com>,
       linux-kernel@vger.kernel.org
Subject: Re: Use of directories to hold root?
Message-ID: <20070812202320.GE21089@ftp.linux.org.uk>
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On Sun, Aug 12, 2007 at 09:49:02PM +0200, Jan Engelhardt wrote:
> 
> On Aug 12 2007 15:39, Mark Cannon wrote:
> >> >> No, but you can use pivot_root.
> >> >
> >> >Or better yet, use an initramfs with MS_MOVE; same as you would with the
> >> >"normal" use of initramfs.
> >
> >I am not sure I understand initramfs with MS_MOVE concept. I will look into
> >it. Any pointers for documentation? 
> 
> pivot_root is atomic afaict, for `mount --move` (which I think Al meant 
> which MS_MOVE - or some C program using mount(2) of your own), you'd 
> need multiple calls to mount.

Move itself is done by a single syscall anyway...