From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753071AbbJNIgh (ORCPT ); Wed, 14 Oct 2015 04:36:37 -0400 Received: from parrot.pmhahn.de ([88.198.50.102]:57327 "EHLO parrot.pmhahn.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751478AbbJNIgc (ORCPT ); Wed, 14 Oct 2015 04:36:32 -0400 X-Greylist: delayed 380 seconds by postgrey-1.27 at vger.kernel.org; Wed, 14 Oct 2015 04:36:32 EDT Message-ID: <561E1293.3050205@pmhahn.de> Date: Wed, 14 Oct 2015 10:30:11 +0200 From: Philipp Hahn User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.8.0 MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: RFH: stale (f)lock in /proc/locks - process no longer exists Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I have several shell scripts using "/usr/bin/flock -x /run/lock/jenkins-ip.lock" to acquiring the exclusive lock. Today they hang, while the lock is owned by a process which no longer exists: # ls -i /run/lock/jenkins-ip.lock 766711440 /run/lock/jenkins-ip.lock # grep 766711440 /proc/locks 1: FLOCK ADVISORY WRITE 1722 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 1725 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 20432 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 20618 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 16235 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 21757 00:12:766711440 0 EOF 1: -> FLOCK ADVISORY WRITE 29151 00:12:766711440 0 EOF # lslocks -o COMMAND,PID,TYPE,MODE,PATH,BLOCKER COMMAND PID TYPE MODE PATH BLOCKER (unknown) 5852 FLOCK WRITE /run cron 489 FLOCK WRITE /run/crond.pid libvirtd 506 POSIX WRITE /run/libvirtd.pid flock 29151 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 flock 21757 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 flock 16235 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 flock 20618 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 flock 20432 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 flock 1725 FLOCK WRITE* /run/lock/jenkins-ip.lock 1722 (unknown) 1722 FLOCK WRITE /run/lock # ps 1722 PID TTY STAT TIME COMMAND # uname -a Linux test4 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt11-1+deb8u3 (2015-08-04) x86_64 GNU/Linux 1. How can this happen? My understanding is, that all files are closed on process exit and that all locks are released then. Did I miss something. 2. How can I release that lock? Thanks in advance Philipp