From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: 3.10.16 cgroup css_set_lock deadlock Date: Fri, 15 Nov 2013 17:19:29 +0900 Message-ID: <20131115081929.GA11530@mtj.dyndns.org> References: <20131114232529.GB16725@sbohrermbp13-local.rgmadvisors.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=kTpQxgkASN22ihmw1gdc/5aLJYM5ErC6apszznyjDsY=; b=hRdStLFiJh9LHkQOp12rRdWm3PWqyZdT45hdhRX5yGUgv+2ZG/8mW244W3nbcUimxA 5lfEMh5fgu+Wcmi/jQiDBBbK8N6ITY42iENrTG/N9Y0ihk0sVb5EV5y7xK2OaSbcbO49 gV3BMtri5gAq6vjjgxQLQE4oCJbIZh0Xn5EOIpkdiwA+5bP+4TYGxScouUgm+yvQ/Ad3 M0h+Q5iJxW4nUoI6mjQa375LFbsIH0t/kEw+BH9uIpr9Ivt2Jg5IFeQtWEievK6Qeh9J FXIUZHIbQVRyVwd5c02eRR3H1nFGvxK4aFqdtrKOhmbNsdYwfhkv2wi5A6fFjXxwV7n1 mFFQ== Content-Disposition: inline In-Reply-To: <20131114232529.GB16725-/vebjAlq/uFE7V8Yqttd03bhEEblAqRIDbRjUBewulXQT0dZR+AlfA@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Shawn Bohrer Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Li Zefan On Thu, Nov 14, 2013 at 05:25:29PM -0600, Shawn Bohrer wrote: > In trying to reproduce the cgroup_mutex deadlock I reported earlier > in https://lkml.org/lkml/2013/11/11/574 I believe I encountered a > different issue that I'm also unable to understand. This machine > started out reporting some soft lockups that look to me like they are > on a read_lock(css_set_lock): > ... > RIP: 0010:[] [] cgroup_attach_task+0xdc/0x7a0 ... > [] attach_task_by_pid+0x167/0x1a0 > [] cgroup_tasks_write+0x13/0x20 Most likely the bug fixed by ea84753c98a7 ("cgroup: fix to break the while loop in cgroup_attach_task() correctly"). 3.10.19 contains the backported fix. Thanks. -- tejun