From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wmauth3.doit.wisc.edu ([144.92.197.226]:39103 "EHLO smtpauth3.wiscmail.wisc.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S964841AbcLTQw3 (ORCPT ); Tue, 20 Dec 2016 11:52:29 -0500 MIME-version: 1.0 Content-type: text/plain; CHARSET=US-ASCII; format=flowed Received: from avs-daemon.smtpauth3.wiscmail.wisc.edu by smtpauth3.wiscmail.wisc.edu (Oracle Communications Messaging Server 8.0.1.1.0 64bit (built Jun 15 2016)) id <0OIH00E00Q9HQE00@smtpauth3.wiscmail.wisc.edu> for linux-btrfs@vger.kernel.org; Tue, 20 Dec 2016 09:52:27 -0600 (CST) Received: from Square-Circle-Consulting-LLC.local (97-88-43-202.dhcp.roch.mn.charter.com [97.88.43.202]) by smtpauth3.wiscmail.wisc.edu (Oracle Communications Messaging Server 8.0.1.1.0 64bit (built Jun 15 2016)) with ESMTPSA id <0OIH0025OQRDPT10@smtpauth3.wiscmail.wisc.edu> for linux-btrfs@vger.kernel.org; Tue, 20 Dec 2016 09:52:27 -0600 (CST) From: David Hanke Subject: btrfs_log2phys: cannot lookup extent mapping To: linux-btrfs@vger.kernel.org Message-id: <89be6fee-5b18-7a9d-11ea-85abeab28022@ece.wisc.edu> Date: Tue, 20 Dec 2016 09:52:25 -0600 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Greetings! I've been using a btrfs-based volume for backups, but lately the system's been filling the syslog with errors like "btrfs_log2phys: cannot lookup extent mapping for 7129125486592" at the rate of hundreds per second. (Please see output below for more details.) Despite the errors, the files I've looked at appear to be written and read successfully. I'm wondering if the contents of the volume are trustworthy and whether this problem is resolvable without backing up, erasing and starting over? Thank you! David # uname -a Linux backup2 3.0.101.RNx86_64.3 #1 SMP Wed Apr 1 16:02:14 PDT 2015 x86_64 GNU/Linux # btrfs --version Btrfs v3.17.3 # btrfs fi show Label: '43f66d40:root' uuid: 6e546e1a-15a3-4e9d-97f7-9693659a5e7e Total devices 1 FS bytes used 571.47MiB devid 1 size 4.00GiB used 3.36GiB path /dev/md0 Label: '43f66d40:data' uuid: 0900d3c7-fda1-463a-81e5-19c04e68a0cb Total devices 1 FS bytes used 27.61TiB devid 1 size 36.34TiB used 27.99TiB path /dev/md127 Btrfs v3.17.3 # dmesg | head s_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 btrfs_log2phys: cannot lookup extent mapping for 7168108658688 # dmesg | tail btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 btrfs_log2phys: cannot lookup extent mapping for 7168110034944 [dmesg.log is filled with 3951 lines of the same type of errors]