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Date: Sun, 20 Mar 2016 19:06:25 +0100
From: Jordi Pujol Palomer <jordipujolp@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linux-Fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH] fs/namei.c: Hard link and rename should check same
 device instead of same mount
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El Wed, 16 Mar 2016 14:25:16 +0000
Al Viro <viro@ZenIV.linux.org.uk> escrigué:

> NAK.  This is absolutely deliberate; moreover, mount --bind $DIR $DIR
> is often used just to set such a boundary.

It means that the way I have proposed may work also ?

Therefore we can develop a new option for binding to let the superuser
choose what is needed for every mount-bind, example:

mount --bind -o boundary $DIR $DIR

mount --bind -o noboundary $DIR1 $DIR2

and allow remount also,

mount -o remount,boundary $DIR

mount -o remount,noboundary $DIR

That seems feasible,

Jordi Pujol i Palomer
Enginyer Tècnic Industrial