From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761509AbdLSIjy (ORCPT ); Tue, 19 Dec 2017 03:39:54 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:48234 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759093AbdLSIjv (ORCPT ); Tue, 19 Dec 2017 03:39:51 -0500 Date: Tue, 19 Dec 2017 09:39:49 +0100 From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: Grygorii Strashko , linux-rt-users , LKML , Sekhar Nori Subject: Re: [v4.9-rt][report] stress-ng: possible circular locking dependency detected Message-ID: <20171219083949.y5l6um5vohfait3g@linutronix.de> References: <20171218200612.7dce6787@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20171218200612.7dce6787@gandalf.local.home> User-Agent: NeoMutt/20171208 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017-12-18 20:06:12 [-0500], Steven Rostedt wrote: > On Mon, 18 Dec 2017 18:55:24 -0600 > Grygorii Strashko wrote: > > > Hi All, > > > > I've tried to run stress-ng on TI am57xx-evm (SMP, 2 cpu) and caught 2 "INFO: possible circular locking dependency detected" > > > > Command 1 (log 1): > > ## stress-ng --class cpu --all 0 -t 5m & stress-ng --class memory --all 0 --vm-bytes 90% -t 5m > > > > Command 2 (log 2): > > ## stress-ng --class os --all 0 -t 5m > > > > actually command 2 often stuck or crushes (Log3 - I've collected 3 different dumps) > > > > I hate to tell you but CPU hotplug is known to be broken on 4.9-rt and > earlier. Hopefully the v4.14-rt code with the redesigned hotplug work > fixes all this. Yes, the v4.9-RT hotplug is not perfect. It works in general but can fall apart with some load or "just" deadlock during CPU-down. The v4.14-RT should not suffer from this and work. > -- Steve Sebastian