From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751611Ab2DRNwq (ORCPT ); Wed, 18 Apr 2012 09:52:46 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:55426 "EHLO e39.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750948Ab2DRNwp (ORCPT ); Wed, 18 Apr 2012 09:52:45 -0400 Date: Wed, 18 Apr 2012 06:51:52 -0700 From: "Paul E. McKenney" To: Steven Rostedt Cc: "Alexander E. Patrakov" , linux-kernel@vger.kernel.org Subject: Re: BUG: sleeping function called from invalid context at kernel/mutex.c:271 Message-ID: <20120418135152.GC2493@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <1334561244.3339.7.camel@aep-desktop> <20120418025626.GB23877@home.goodmis.org> <20120418040636.GD2449@linux.vnet.ibm.com> <1334724679.2019.20.camel@aep-desktop> <1334750926.28106.36.camel@gandalf.stny.rr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1334750926.28106.36.camel@gandalf.stny.rr.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12041813-4242-0000-0000-00000161F39E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 18, 2012 at 08:08:46AM -0400, Steven Rostedt wrote: > On Wed, 2012-04-18 at 10:51 +0600, Alexander E. Patrakov wrote: > > > > > > > > > Hmm, this can also be reported if you have an rcu leak. Which would also > > > > explain your memory leak. RCU is the kernel's "garbage collector" and if > > > > it gets stuck, then you will definitely start seeing memory leaks, as > > > > memory wont be freed. > > > > > > If RCU is stuck, you should see RCU CPU stall warnings, which can > > > give clues as to what is causing RCU to get stuck. > > > > Yes, there were such warnings, but all of them said that the stall ended > > before dump start. So nothing reportable here, but I have just found > > that https://bugzilla.novell.com/show_bug.cgi?id=754186 looks quite > > similar in the sense that it (and duplicates) also has undumpable stalls > > of increasing length, and IPv6 is in use both at home and at work. > > > > Do you see the RT throttling message too? That's a bug with an RT task > going haywire. If that is happening, an RT task may be preventing an RCU > grace period to finish, and causing the RCU stalls. Hmmm... Maybe I should revisit running the RCU core processing in real-time kernel threads... Though it was quite painful the last time I tried that. Thanx, Paul > Just because they ended, doesn't mean that the problem went a way. If > RCU is being blocked, you will start to see memory leaks. As I said, RCU > works as the kernels garbage collector. If it stops or just slows down > significantly, memory does not get freed. > > -- Steve > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ >