From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Kenton Date: Tue, 10 Mar 2015 11:16:20 -0500 Subject: [Buildroot] Obscure bug in Util-Linux umount? In-Reply-To: <54FE7E8E.20306@ou.edu> References: <54FE7E8E.20306@ou.edu> Message-ID: <54FF18D4.2030709@ou.edu> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 03/10/2015 12:18 AM, Steve Kenton wrote: > I *think* this is an obscure bug in the util-linux version of umount, but I wonder if anyone else has run into it. It drove me nuts for a while. Here's a short description. Further testing revealed that it only occurs if the embedded root filesystem is read-only which I forgot to mention (blush) so it's probably an interaction with a stale /etc/mtab or something, but only for the root filesystem and only if the mount point directory names are the same, yada etc. Much less likely to bite anyone else so I guess a heads up is not needed. Any way, not really a bug but rather a feature with undefined behaviour and most importantly a case of 'it hurts if I do this' soooo 'don't do that'! Sorry for the noise. Steve