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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY autolearn=no 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 D9DEAC43331 for ; Fri, 27 Mar 2020 01:51:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A92D42082D for ; Fri, 27 Mar 2020 01:51:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="kgeOGsuB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727607AbgC0BvB (ORCPT ); Thu, 26 Mar 2020 21:51:01 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:46504 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727122AbgC0BvA (ORCPT ); Thu, 26 Mar 2020 21:51:00 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 02R1o3QK102384; Fri, 27 Mar 2020 01:50:55 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=to : cc : subject : from : references : date : in-reply-to : message-id : mime-version : content-type; s=corp-2020-01-29; bh=3qGek2yKWQLijs+5JbpVCUiG2M8HpMlzKySDTcmY8YM=; b=kgeOGsuB5EhESLZic4SdXkd8oeZ+hhPTA2H8QZYOyiuVElVwjSIboUJEN1475BrSKkuz +pjdH8jzWyp7rbRfSOH0OhcE7FxL+k9iwK1VW7mGgKkUjStZaFiUkkNOGYiAQRfjwe69 qo0Xbqzf7tGwmxN8+SbDBZ6DeNFM/mzmhc4SG5ai28dWyEh9GjTAKH1S8tKnR7vbpI6o ODVJ7QLmrAlVh/TbR+DAEJrolgw3eEnMSEKYZhtHY7A/mN6lh6OpKBAc15teXvrwp967 1ikjVQaA8sdGC8aQr2qVw1hEtQ6Dz6Kdzzr4GfTUDsWaL+eTrGgK07R5bmjKqZp++bgd mg== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 300urk3m79-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 27 Mar 2020 01:50:55 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 02R1oDsx166315; Fri, 27 Mar 2020 01:50:54 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3030.oracle.com with ESMTP id 3006r9fskt-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 27 Mar 2020 01:50:54 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 02R1ooWJ000698; Fri, 27 Mar 2020 01:50:52 GMT Received: from ca-mkp.ca.oracle.com (/10.159.214.123) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 26 Mar 2020 18:50:50 -0700 To: Sreekanth Reddy Cc: "Elliott\, Robert \(Servers\)" , "martin.petersen\@oracle.com" , "linux-scsi\@vger.kernel.org" , "sathya.prakash\@broadcom.com" , "suganath-prabu.subramani\@broadcom.com" , "stable\@vger.kernel.org" , "amit\@kernel.org" Subject: Re: [PATCH] mpt3sas: Fix kernel panic observed on soft HBA unplug From: "Martin K. Petersen" Organization: Oracle Corporation References: <1583923013-3935-1-git-send-email-sreekanth.reddy@broadcom.com> Date: Thu, 26 Mar 2020 21:50:47 -0400 In-Reply-To: (Sreekanth Reddy's message of "Mon, 16 Mar 2020 11:45:15 +0530") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1.92 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9572 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 adultscore=0 suspectscore=0 phishscore=0 spamscore=0 mlxscore=0 mlxlogscore=680 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003270012 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9572 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 spamscore=0 mlxlogscore=741 clxscore=1011 lowpriorityscore=0 mlxscore=0 phishscore=0 bulkscore=0 impostorscore=0 adultscore=0 malwarescore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2003270012 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Sreekanth, > In the unload path driver call sas_remove_host() API before releasing > the resources. This sas_remove_host() API waits for all the > outstanding IOs to be completed. So here, indirectly driver is waiting > for the outstanding IOs to be processed before releasing the HBA > resources. So only in the cases where HBA is inaccessible (e.g. HBA > unplug case), driver is flushing out the outstanding commands to avoid > SCSI error handling over head and can quilkey complete the driver > unload operation. None of this is clear from the commit description. Please resubmit patch with a new description clarifying why and when it is safe to drop outstanding commands. -- Martin K. Petersen Oracle Linux Engineering