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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 3B4E4C43613 for ; Mon, 24 Jun 2019 05:21:22 +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 5626B208CA for ; Mon, 24 Jun 2019 05:21:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5626B208CA 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 45XHhG1lw7zDqTd for ; Mon, 24 Jun 2019 15:21:18 +1000 (AEST) 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=mahesh@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 45XHf75mWgzDqSg for ; Mon, 24 Jun 2019 15:19:26 +1000 (AEST) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x5O5H8O9142976 for ; Mon, 24 Jun 2019 01:19:22 -0400 Received: from e06smtp01.uk.ibm.com (e06smtp01.uk.ibm.com [195.75.94.97]) by mx0a-001b2d01.pphosted.com with ESMTP id 2taqua0ssn-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 24 Jun 2019 01:19:22 -0400 Received: from localhost by e06smtp01.uk.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) Mon, 24 Jun 2019 06:19:16 +0100 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x5O5JE6634406676 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 24 Jun 2019 05:19:14 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CB2244C04A; Mon, 24 Jun 2019 05:19:14 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CED234C040; Mon, 24 Jun 2019 05:19:12 +0000 (GMT) Received: from [9.109.198.148] (unknown [9.109.198.148]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 24 Jun 2019 05:19:12 +0000 (GMT) Subject: Re: [PATCH 05/13] powerpc/mce: Allow notifier callback to handle MCE To: Reza Arbab References: <196df6a74f259c041a4269e6cba026a1248ed4af.1561020760.git.santosh@fossix.org> <20190623021401.al2iyyhxvkf7csep@arbab-vm> From: Mahesh Jagannath Salgaonkar Date: Mon, 24 Jun 2019 10:49:11 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190623021401.al2iyyhxvkf7csep@arbab-vm> Content-Type: text/plain; charset=utf-8 Content-Language: en-MW Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19062405-4275-0000-0000-000003450065 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19062405-4276-0000-0000-0000385536EE Message-Id: <8eb93794-fdbc-5f24-08d7-d698b6ce6f06@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-24_05:, , 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=556 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906240044 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: Santosh Sivaraj , "Aneesh Kumar K.V" , Mahesh Salgaonkar , Nicholas Piggin , Chandan Rajendra , linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 6/23/19 7:44 AM, Reza Arbab wrote: > Hi Mahesh, > > On Fri, Jun 21, 2019 at 12:35:08PM +0530, Mahesh Jagannath Salgaonkar > wrote: >> On 6/21/19 6:27 AM, Santosh Sivaraj wrote: >>> -    blocking_notifier_call_chain(&mce_notifier_list, 0, &evt); >>> +    rc = blocking_notifier_call_chain(&mce_notifier_list, 0, evt); >>> +    if (rc & NOTIFY_STOP_MASK) { >>> +        evt->disposition = MCE_DISPOSITION_RECOVERED; >>> +        regs->msr |= MSR_RI; >> >> What is the reason for setting MSR_RI ? I don't think this is a good >> idea. MSR_RI = 0 means system got MCE interrupt when SRR0 and SRR1 >> contents were live and was overwritten by MCE interrupt. Hence this >> interrupt is unrecoverable irrespective of whether machine check handler >> recovers from it or not. > > Good catch! I think this is an artifact from when I was first trying to > get all this working. > > Instead of setting MSR_RI, we should probably just check for it. Ie, > >     if ((rc & NOTIFY_STOP_MASK) && (regs->msr & MSR_RI)) { >         evt->disposition = MCE_DISPOSITION_RECOVERED; Yup, looks good to me. Thanks, -Mahesh.