From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mgwym02.jp.fujitsu.com ([211.128.242.41]:52733 "EHLO mgwym02.jp.fujitsu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752184AbeAREYT (ORCPT ); Wed, 17 Jan 2018 23:24:19 -0500 Received: from g01jpfmpwkw01.exch.g01.fujitsu.local (g01jpfmpwkw01.exch.g01.fujitsu.local [10.0.193.38]) by yt-mxq.gw.nic.fujitsu.com (Postfix) with ESMTP id 5D29CAC0150 for ; Thu, 18 Jan 2018 13:24:14 +0900 (JST) Received: from g01jpexchkw36.g01.fujitsu.local (unknown [10.0.193.4]) by g01jpfmpwkw01.exch.g01.fujitsu.local (Postfix) with ESMTP id A14B96924C0 for ; Thu, 18 Jan 2018 13:24:13 +0900 (JST) From: "Misono, Tomohiro" Subject: bug report: mounting the same device to different mount points in parallel may fail To: linux-btrfs Message-ID: Date: Thu, 18 Jan 2018 13:23:35 +0900 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-btrfs-owner@vger.kernel.org List-ID: Although I think this rarely happens in the real world, mounting the same device to different mount points in parallel may fail: - kernel 4.15.0-rc8 - Procedure [mount.sh] #!/bin/bash for i in `seq 1 1000`; do echo $i mount $1 $2 umount $2 if [ $? -ne 0 ]; then exit 1; fi done $ mkfs.btrfs -f /dev/sde $ ./mount.sh /dev/sde /mnt $ ./mount.sh /dev/sde /mnt2 (on the different terminal) - stdout mount: /mnt2: wrong fs type, bad option, bad superblock on /dev/sde, missing codepage or helper program, or other error. - dmesg [ 108.122576] BTRFS error (device sde): super_total_bytes 199481098240 mismatch with fs_devices total_rw_bytes 398962196480 [ 108.122647] BTRFS error (device sde): failed to read chunk tree: -22 [ 108.150060] BTRFS error (device sde): open_ctree failed xfs or ext4 works fine. Regards, Tomohiro Misono