From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail2.unitix.de ([176.9.2.175]:53007 "EHLO mail2.unitix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752246Ab2GIWXI (ORCPT ); Mon, 9 Jul 2012 18:23:08 -0400 Received: from [192.168.1.64] (77-216.eduroam.rwth-aachen.de [134.61.77.216]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail2.unitix.de (Postfix) with ESMTPSA id C945A655D for ; Tue, 10 Jul 2012 00:23:05 +0200 (CEST) Message-ID: <4FFB59BF.1050104@arndnet.de> Date: Tue, 10 Jul 2012 00:22:55 +0200 From: Arnd Hannemann MIME-Version: 1.0 To: linux-btrfs@vger.kernel.org Subject: 3.5.0-rc6: btrfs and LVM snapshots -> wrong devicename in /proc/mounts Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi, using btrfs with LVM snapshots seems to be confusing /proc/mounts After mounting a snapshot of an original filesystem, the devicename of the original filesystem is overwritten with that of the snapshot in /proc/mounts. Steps to reproduce: arnd@kallisto:/mnt$ sudo mount /dev/vg0/original /mnt/original [ 107.041432] device fsid 5c3e8ca2-da56-4ade-9fef-103a6a8a70c2 devid 1 transid 4 /dev/mapper/vg0-original [ 107.044691] btrfs: no dev_stats entry found for device /dev/mapper/vg0-original (devid 1) (OK on first mount after mkfs) arnd@kallisto:/mnt$ cat /proc/mounts | grep /mnt /dev/mapper/vg0-original /mnt/original btrfs rw,relatime,ssd,space_cache 0 0 arnd@kallisto:/mnt$ sudo lvcreate -L 10M --snap --name snapshot /dev/vg0/original arnd@kallisto:/mnt$ sudo mount /dev/vg0/testsnap /mnt/testsnap [ 215.432281] device fsid 5c3e8ca2-da56-4ade-9fef-103a6a8a70c2 devid 1 transid 4 /dev/mapper/vg0-testsnap arnd@kallisto:/mnt$ cat /proc/mounts | grep /mnt /dev/mapper/vg0-testsnap /mnt/original btrfs rw,relatime,ssd,space_cache 0 0 /dev/mapper/vg0-testsnap /mnt/testsnap btrfs rw,relatime,ssd,space_cache 0 0 arnd@kallisto:/mnt$ sudo umount /dev/vg0/testsnap arnd@kallisto:/mnt$ cat /proc/mounts | grep /mnt /dev/mapper/vg0-testsnap /mnt/original btrfs rw,relatime,ssd,space_cache 0 0 Best regards, Arnd