From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751856AbdKHRoZ (ORCPT ); Wed, 8 Nov 2017 12:44:25 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:43738 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751352AbdKHRoY (ORCPT ); Wed, 8 Nov 2017 12:44:24 -0500 Date: Wed, 8 Nov 2017 09:44:19 -0800 From: "Paul E. McKenney" To: Jeremy Linton Cc: Davidlohr Bueso , Peter Zijlstra , linux-kernel@vger.kernel.org, mingo@redhat.com, josh@joshtriplett.org Subject: Re: [PATCH] locktorture: Fix Oops when reader/writer count is 0 Reply-To: paulmck@linux.vnet.ibm.com References: <20171010155248.11602-1-jeremy.linton@arm.com> <20171107210748.GR3165@worktop.lehotels.local> <20171107221555.GX3624@linux.vnet.ibm.com> <20171108144523.k7ouldzwuawje4wc@linux-n805> <20171108164855.GK3624@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 17110817-0040-0000-0000-000003BF4489 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00008033; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000239; SDB=6.00942997; UDB=6.00475735; IPR=6.00723284; BA=6.00005679; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00017913; XFM=3.00000015; UTC=2017-11-08 17:44:21 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17110817-0041-0000-0000-000007B45E8B Message-Id: <20171108174419.GL3624@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-11-08_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1711080235 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 08, 2017 at 10:57:07AM -0600, Jeremy Linton wrote: > On 11/08/2017 10:48 AM, Paul E. McKenney wrote: > >On Wed, Nov 08, 2017 at 06:45:23AM -0800, Davidlohr Bueso wrote: > >>On Tue, 07 Nov 2017, Paul E. McKenney wrote: > >> > >>>On Tue, Nov 07, 2017 at 10:07:48PM +0100, Peter Zijlstra wrote: > >>>>On Tue, Nov 07, 2017 at 02:01:58PM -0600, Jeremy Linton wrote: > >>>>>Hi, > >>>>> > >>>>>On 10/10/2017 10:52 AM, Jeremy Linton wrote: > >>>>>>If nwriters_stress=0 is passed to the lock torture test > >>>>>>it will panic in: > >>>>> > >>>>>Ping? > >>>>> > >>>>>Has anyone had a chance to look at this? > >>>> > >>>>Helps if you Cc the people actually working on this stuff of course... > >>> > >>>Thank you for the forward, Peter, I have queued Jeremy's patch for > >>>testing and review. > >> > >>fyi I had proposed the following a while back, which I think is more > >>complete than this patch: > >> > >>https://lkml.org/lkml/2017/5/15/201 > >> > >>Ah, there's also this (unrelated) fix: > >>https://lkml.org/lkml/2017/5/15/203 > >> > >>>But Jeremy's list of email addresses is what you would expect from > >>>looking at MAINTAINERS, so how about the following patch? > > > >And it looks like Jeremy was not alone -- I was not CCed on either > >of those patches, either. > > > >Dave's patch does look more complete, and it certainly was submitted > >first. Let's see if it still applies... And they both do. > > Yes, avoiding the zero length allocations is probably a good plan, > and complaining if both the reader and writer are zero is doesn't > hurt either. > > So, I'm good with that patch too.. > > Reviewed-by: Jeremy Linton Thank you! > >Jeremy, could you please test Dave's patches and make sure that they > >work for you? That way I can apply your Tested-by. Dave, any objection > >to my adding Jeremy's Reported-by to your /201 patch? > > I will give it a spin.. Very good! Looking forward to seeing the results. Thanx, Paul > >>>------------------------------------------------------------------------ > >>> > >>>commit 58322063498c8f5a3cc88f95bee237a0ce81f70a > >>>Author: Paul E. McKenney > >>>Date: Tue Nov 7 14:10:03 2017 -0800 > >>> > >>> torture: Place all torture-test modules in one MAINTAINERS group > >>> > >>> There is some confusion about where patches to kernel/torture.c > >>> and kernel/locking/locktorture.c should be sent. This commit > >>> therefore updates MAINTAINERS appropriately. > >>> > >>> Reported-by: Peter Zijlstra > >>> Signed-off-by: Paul E. McKenney > >>> > >>>diff --git a/MAINTAINERS b/MAINTAINERS > >>>index 2d3d750b19c0..eab868adedc6 100644 > >>>--- a/MAINTAINERS > >>>+++ b/MAINTAINERS > >>>@@ -8091,6 +8091,7 @@ F: arch/*/include/asm/rwsem.h > >>>F: include/linux/seqlock.h > >>>F: lib/locking*.[ch] > >>>F: kernel/locking/ > >>>+X: kernel/locking/locktorture.c > >>> > >>>LOGICAL DISK MANAGER SUPPORT (LDM, Windows 2000/XP/Vista Dynamic Disks) > >>>M: "Richard Russon (FlatCap)" > >>>@@ -11318,15 +11319,6 @@ L: linux-wireless@vger.kernel.org > >>>S: Orphan > >>>F: drivers/net/wireless/ray* > >>> > >>>-RCUTORTURE MODULE > >>>-M: Josh Triplett > >>>-M: "Paul E. McKenney" > >>>-L: linux-kernel@vger.kernel.org > >>>-S: Supported > >>>-T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git > >>>-F: Documentation/RCU/torture.txt > >>>-F: kernel/rcu/rcutorture.c > >>>- > >>>RCUTORTURE TEST FRAMEWORK > >>>M: "Paul E. McKenney" > >>>M: Josh Triplett > >>>@@ -13558,6 +13550,18 @@ L: platform-driver-x86@vger.kernel.org > >>>S: Maintained > >>>F: drivers/platform/x86/topstar-laptop.c > >>> > >>>+TORTURE-TEST MODULES > >>>+M: Davidlohr Bueso > >>>+M: "Paul E. McKenney" > >>>+M: Josh Triplett > >>>+L: linux-kernel@vger.kernel.org > >>>+S: Supported > >>>+T: git git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git > >>>+F: Documentation/RCU/torture.txt > >>>+F: kernel/torture.c > >>>+F: kernel/rcu/rcutorture.c > >>>+F: kernel/locking/locktorture.c > >> > >>Sure, if you think this is the best way to go, I have no problem. > >> > >>Thanks, > >>Davidlohr > >> > > >