From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E2FEC6783C for ; Tue, 11 Dec 2018 22:14:37 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EBBD82084E for ; Tue, 11 Dec 2018 22:14:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EBBD82084E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43DvPQ4R91zDqVD for ; Wed, 12 Dec 2018 09:14:34 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=mwb@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43DvL13TChzDqkR for ; Wed, 12 Dec 2018 09:11:37 +1100 (AEDT) Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wBBM8xnc004537 for ; Tue, 11 Dec 2018 17:11:35 -0500 Received: from e17.ny.us.ibm.com (e17.ny.us.ibm.com [129.33.205.207]) by mx0a-001b2d01.pphosted.com with ESMTP id 2pamu1jhyg-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 11 Dec 2018 17:11:35 -0500 Received: from localhost by e17.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 11 Dec 2018 22:11:30 -0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wBBMBT8420512828 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 11 Dec 2018 22:11:29 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8A3DE112066; Tue, 11 Dec 2018 22:11:29 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id E4D7B112065; Tue, 11 Dec 2018 22:11:28 +0000 (GMT) Received: from oc5000245537.ibm.com (unknown [9.53.179.223]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Tue, 11 Dec 2018 22:11:28 +0000 (GMT) Subject: Re: [PATCH] pseries/hotplug: Add more delay in pseries_cpu_die while waiting for rtas-stop To: Thiago Jung Bauermann References: <1544095908-2414-1-git-send-email-ego@linux.vnet.ibm.com> <87a7li5zv2.fsf@morokweng.localdomain> <20181207104311.GA11431@in.ibm.com> <20181207120346.GB11431@in.ibm.com> <87va443fm3.fsf@morokweng.localdomain> <06dfb955-6af9-ae23-3919-9bee447cfcdc@linux.vnet.ibm.com> <87a7ld3yz4.fsf@morokweng.localdomain> From: Michael Bringmann Openpgp: preference=signencrypt Autocrypt: addr=mwb@linux.vnet.ibm.com; prefer-encrypt=mutual; keydata= xsBNBFcY7GcBCADzw3en+yzo9ASFGCfldVkIg95SAMPK0myXp2XJYET3zT45uBsX/uj9/2nA lBmXXeOSXnPfJ9V3vtiwcfATnWIsVt3tL6n1kqikzH9nXNxZT7MU/7gqzWZngMAWh/GJ9qyg DTOZdjsvdUNUWxtiLvBo7y+reA4HjlQhwhYxxvCpXBeRoF0qDWfQ8DkneemqINzDZPwSQ7zY t4F5iyN1I9GC5RNK8Y6jiKmm6bDkrrbtXPOtzXKs0J0FqWEIab/u3BDrRP3STDVPdXqViHua AjEzthQbGZm0VCxI4a7XjMi99g614/qDcXZCs00GLZ/VYIE8hB9C5Q+l66S60PLjRrxnABEB AAHNLU1pY2hhZWwgVy4gQnJpbmdtYW5uIDxtd2JAbGludXgudm5ldC5pYm0uY29tPsLAeAQT AQIAIgUCVxjsZwIbAwYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQSEdag3dpuTI0NAf8 CKYTDKQLgOSjVrU2L5rM4lXaJRmQV6oidD3vIhKSnWRvPq9C29ifRG6ri20prTHAlc0vycgm 41HHg0y2vsGgNXGTWC2ObemoZBI7mySXe/7Tq5mD/semGzOp0YWZ7teqrkiSR8Bw0p+LdE7K QmT7tpjjvuhrtQ3RRojUYcuy1nWUsc4D+2cxsnZslsx84FUKxPbLagDgZmgBhUw/sUi40s6S AkdViVCVS0WANddLIpG0cfdsV0kCae/XdjK3mRK6drFKv1z+QFjvOhc8QIkkxFD0da9w3tJj oqnqHFV5gLcHO6/wizPx/NV90y6RngeBORkQiRFWxTXS4Oj9GVI/Us7ATQRXGOxnAQgAmJ5Y ikTWrMWPfiveUacETyEhWVl7u8UhZcx3yy2te8O0ay7t9fYcZgIEfQPPVVus89acIXlG3wYL DDPvb21OprLxi+ZJ2a0S5we+LcSWN1jByxJlbWBq+/LcMtGAOhNLpysY1gD0Y4UW/eKS+TFZ 562qKC3k1dBvnV9JXCgeS1taYFxRdVAn+2DwK3nuyG/DDq/XgJ5BtmyC3MMx8CiW3POj+O+l 6SedIeAfZlZ7/xhijx82g93h07VavUQRwMZgZFsqmuxBxVGiav2HB+dNvs3PFB087Pvc9OHe qhajPWOP/gNLMmvBvknn1NToM9a8/E8rzcIZXoYs4RggRRYh6wARAQABwsBfBBgBAgAJBQJX GOxnAhsMAAoJEEhHWoN3abky+RUH/jE08/r5QzaNKYeVhu0uVbgXu5fsxqr2cAxhf+KuwT3T efhEP2alarxzUZdEh4MsG6c+X2NYLbD3cryiXxVx/7kSAJEFQJfA5P06g8NLR25Qpq9BLsN7 ++dxQ+CLKzSEb1X24hYAJZpOhS8ev3ii+M/XIo+olDBKuTaTgB6elrg3CaxUsVgLBJ+jbRkW yQe2S5f/Ja1ThDpSSLLWLiLK/z7+gaqwhnwjQ8Z8Y9D2itJQcj4itHilwImsqwLG7SxzC0NX IQ5KaAFYdRcOgwR8VhhkOIVd70ObSZU+E4pTET1WDz4o65xZ89yfose1No0+r5ht/xWOOrh8 53/hcWvxHVs= Organization: IBM Linux Technology Center Date: Tue, 11 Dec 2018 16:11:28 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <87a7ld3yz4.fsf@morokweng.localdomain> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 18121122-0040-0000-0000-000004A115AD X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010214; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000270; SDB=6.01130391; UDB=6.00577119; IPR=6.00910525; MB=3.00024658; MTD=3.00000008; XFM=3.00000015; UTC=2018-12-11 22:11:32 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18121122-0041-0000-0000-000008AA3604 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-12-11_07:, , 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-1812110195 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ego@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Nicholas Piggin , Tyrel Datwyler Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Note from Scott Mayes on latest crash: Michael, Since the partition crashed, I was able to get the last .2 seconds worth of RTAS call trace leading up to the crash. Best I could tell from that bit of trace was that the removal of a processor involved the following steps: -- Call to stop-self for a given thread -- Repeated calls to query-cpu-stopped-state (which eventually indicated the thread was stopped) -- Call to get-sensor-state for the thread to check its entity-state (9003) sensor which returned 'dr-entity-present' -- Call to set-indicator to set the isolation-state (9001) indicator to ISOLATE state -- Call to set-indicator to set the allocation-state (9003) indicator to UNUSABLE state I noticed one example of thread x28 getting through all of these steps just fine, but for thread x20, although the query-cpu-stopped state returned 0 status (STOPPED), a subsequent call to set-indicator to ISOLATE failed. This failure was near the end of the trace, but was not the very last RTAS call made in the trace. The set-indicator failure reported to Linux was a -9001 (Valid outstanding translation) which was mapped from a 0x502 (Invalid thread state) return code from PHYP's H_SET_DR_STATE h-call. On 12/10/2018 02:31 PM, Thiago Jung Bauermann wrote: > > Hello Michael, > > Michael Bringmann writes: > >> I have asked Scott Mayes to take a look at one of these crashes from >> the phyp side. I will let you know if he finds anything notable. > > Thanks! It might make sense to test whether booting with > cede_offline=off makes the bug go away. Scott is looking at the system. I will try once he is finished. > > One suspicion I have is regarding the code handling CPU_STATE_INACTIVE. >>>From what I understand, it is a powerpc-specific CPU state and from the > perspective of the generic CPU hotplug state machine, inactive CPUs are > already fully offline. Which means that the locking performed by the > generic code state machine doesn't apply to transitioning CPUs from > INACTIVE to OFFLINE state. Perhaps the bug is that there is more than > one CPU making that transition at the same time? That would cause two > CPUs to call RTAS stop-self. > > I haven't checked whether this is really possible or not, though. It's > just a conjecture. Michael > > -- > Thiago Jung Bauermann > IBM Linux Technology Center > > -- Michael W. Bringmann Linux Technology Center IBM Corporation Tie-Line 363-5196 External: (512) 286-5196 Cell: (512) 466-0650 mwb@linux.vnet.ibm.com