From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Subject: Behavior of 'mount --bind' and umount
Date: Fri, 27 Dec 2013 18:18:49 +0100
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Hi all,

I've a question about this command.
Let's take a simple test:
$ touch foo
$ echo foo > foo
$ touch bar
$ mount --bind foo bar
$ cat bar
foo
$ umount foo

On some files system/distribution/kernel, the last command returns an error
(on debian for example):
$ umount foo
umount: foo: not mounted

or unmount bar (on ubuntu for example):
$ umount foo
$ cat bar
$

I did not find the reason of this difference, any help is welcome.


Thank you,
Nicolas