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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Fri, 21 Jun 2019 13:16:30 +0100 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5LCGTlG40501682 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 21 Jun 2019 12:16:29 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B9EB7B2067; Fri, 21 Jun 2019 12:16:29 +0000 (GMT) Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 9A452B205F; Fri, 21 Jun 2019 12:16:29 +0000 (GMT) Received: from paulmck-ThinkPad-W541 (unknown [9.85.175.77]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP; Fri, 21 Jun 2019 12:16:29 +0000 (GMT) Received: by paulmck-ThinkPad-W541 (Postfix, from userid 1000) id 13BF116C4086; Fri, 21 Jun 2019 05:16:30 -0700 (PDT) Date: Fri, 21 Jun 2019 05:16:30 -0700 From: "Paul E. McKenney" To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, frederic@kernel.org, tglx@linutronix.de Subject: Re: [PATCH] time/tick-broadcast: Fix tick_broadcast_offline() lockdep complaint Reply-To: paulmck@linux.ibm.com References: <20190619181903.GA14233@linux.ibm.com> <20190620121032.GU3436@hirez.programming.kicks-ass.net> <20190620160118.GQ26519@linux.ibm.com> <20190620211019.GA3436@hirez.programming.kicks-ass.net> <20190620221336.GZ26519@linux.ibm.com> <20190621105503.GI3436@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190621105503.GI3436@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 19062112-2213-0000-0000-000003A26D64 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00011302; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000286; SDB=6.01221169; UDB=6.00642455; IPR=6.01002307; MB=3.00027406; MTD=3.00000008; XFM=3.00000015; UTC=2019-06-21 12:16:32 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19062112-2214-0000-0000-00005EF07DA7 Message-Id: <20190621121630.GE26519@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-06-21_09:,, 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 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906210104 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 21, 2019 at 12:55:03PM +0200, Peter Zijlstra wrote: > On Thu, Jun 20, 2019 at 03:13:36PM -0700, Paul E. McKenney wrote: > > So how about the following patch, which passes very light rcutorture > > testing but should otherwise be regarded as being under suspicion? > > Looks good to me, > > Acked-by: Peter Zijlstra (Intel) Thank you! But... > Or, if you want me to apply it, I can do that too ;-) Last night's rcutorture run was not amused. Looking into it... A pair of full hangs at boot (TASKS03 and TREE04), no console output whatsoever. Not sure how these changes could cause that, but suspicion falls on sched_tick_offload_init(). Though even that is a bit strange because if so, why didn't TREE01 and TREE07 also hang? Again, looking into it. Thanx, Paul