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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,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 17004C282C0 for ; Fri, 25 Jan 2019 21:12:52 +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 3AAA32184C for ; Fri, 25 Jan 2019 21:12:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3AAA32184C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.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 43mWvN5v6RzDqQy for ; Sat, 26 Jan 2019 08:12:48 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=fbarrat@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 43mWsj3RJLzDqQG for ; Sat, 26 Jan 2019 08:11:21 +1100 (AEDT) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x0PKrXup175733 for ; Fri, 25 Jan 2019 16:11:19 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0b-001b2d01.pphosted.com with ESMTP id 2q86v485xr-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Fri, 25 Jan 2019 16:11:18 -0500 Received: from localhost by e06smtp05.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) Fri, 25 Jan 2019 21:11:16 -0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x0PLBEUF4850158 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 25 Jan 2019 21:11:14 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 340A6A4059; Fri, 25 Jan 2019 21:11:14 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id C5B29A4053; Fri, 25 Jan 2019 21:11:12 +0000 (GMT) Received: from [9.85.169.234] (unknown [9.85.169.234]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 25 Jan 2019 21:11:12 +0000 (GMT) Subject: Re: [PATCH] cxl: Wrap iterations over afu slices inside 'afu_list_lock' To: Vaibhav Jain , linuxppc-dev@lists.ozlabs.org References: <20190125044052.32059-1-vaibhav@linux.ibm.com> From: Frederic Barrat Date: Fri, 25 Jan 2019 15:11:11 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20190125044052.32059-1-vaibhav@linux.ibm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19012521-0020-0000-0000-0000030B86C5 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19012521-0021-0000-0000-0000215CCE2D Message-Id: <4a90ada0-99dc-df32-7331-ffb3191ebf40@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-01-25_13:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 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-1901250161 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: Philippe Bergheaud , Alastair D'Silva , Christophe Lombard , Andrew Donnellan Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" > diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c > index c79ba1c699ad..28c28bceb063 100644 > --- a/drivers/misc/cxl/pci.c > +++ b/drivers/misc/cxl/pci.c > @@ -1932,14 +1935,20 @@ static pci_ers_result_t cxl_pci_error_detected(struct pci_dev *pdev, > * * In slot_reset, free the old resources and allocate new ones. > * * In resume, clear the flag to allow things to start. > */ > + > + /* Make sure no one else changes the afu list */ > + spin_lock(&adapter->afu_list_lock); > + > for (i = 0; i < adapter->slices; i++) { > afu = adapter->afu[i]; > > afu_result = cxl_vphb_error_detected(afu, state); > > - cxl_context_detach_all(afu); > - cxl_ops->afu_deactivate_mode(afu, afu->current_mode); > - pci_deconfigure_afu(afu); > + if (afu != NULL) { > + cxl_context_detach_all(afu); > + cxl_ops->afu_deactivate_mode(afu, afu->current_mode); > + pci_deconfigure_afu(afu); > + } I can see you're also checking if cxl_vphb_error_detected() is called with a NULL afu from within the function, but why not move the call to cxl_vphb_error_detected() within that "if (afu != NULL)... " statement? Otherwise, it looks suspicious when reading the code. > @@ -2051,10 +2067,11 @@ static void cxl_pci_resume(struct pci_dev *pdev) > * This is not the place to be checking if everything came back up > * properly, because there's no return value: do that in slot_reset. > */ > + spin_lock(&adapter->afu_list_lock); > for (i = 0; i < adapter->slices; i++) { > afu = adapter->afu[i]; > > - if (afu->phb == NULL) > + if (afu || afu->phb == NULL) > continue; if (afu == NULL ... Fred