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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_MUTT 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 3EB25C43387 for ; Thu, 17 Jan 2019 09:17:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E7C920855 for ; Thu, 17 Jan 2019 09:17:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="xrKDs/KU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727709AbfAQJRO (ORCPT ); Thu, 17 Jan 2019 04:17:14 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:51584 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725900AbfAQJRO (ORCPT ); Thu, 17 Jan 2019 04:17:14 -0500 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id x0H9DrkR087298; Thu, 17 Jan 2019 09:17:05 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2018-07-02; bh=17gCzCsVba/t/B3wS0SMg4RzfPAP4ovajvLZ0tomFJ4=; b=xrKDs/KUfJR/ZLp+FuLTmI6Nv4y/Mu8gu1NgqOQ1fJ0KcJjbIO5AMaPuSMgRTXhpMBjY ygvJInce/KCLuN6t1S5K8wA1rqwXcC2Wd1x0y5eA4sYgHMD/eOJrePX83YTkPtwptSGE qVUcdHeU0Rh55vdkv+OAFxE7pPaDFPBkmM/CQhBrTT5t4FlUZXMr8wCl18t5yE1BDFsp r3v5AJbZq8nB9Fc2Ds6ZpsCHtYWxpRcVSv1RGpknQcA3tSVgFFxx00AkXh3dy+Bpk66r FTI99lIcWjPCYWIsOUhAHF7RTfBKTxyLze6XVdIiDnB3byN6LNXeQvnd5wiv+zr1czdT KQ== Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp2120.oracle.com with ESMTP id 2pybjseq2g-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 17 Jan 2019 09:17:05 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id x0H9H49i003943 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 17 Jan 2019 09:17:04 GMT Received: from abhmp0018.oracle.com (abhmp0018.oracle.com [141.146.116.24]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x0H9H290008422; Thu, 17 Jan 2019 09:17:03 GMT Received: from kadam (/197.157.0.55) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 17 Jan 2019 01:17:02 -0800 Date: Thu, 17 Jan 2019 12:16:46 +0300 From: Dan Carpenter To: Ching Huang Cc: martin.petersen@oracle.com, James.Bottomley@HansenPartnership.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, hch@infradead.org, colin.king@canonical.com Subject: Re: [PATCH 2/3] scsi: arcmsr: Fix suspend/resume of ACB_ADAPTER_TYPE_B part 2 Message-ID: <20190117091646.GA11828@kadam> References: <1547696703.4339.21.camel@Centos6.3-64> <20190117070227.GM4504@kadam> <1547714827.5079.19.camel@Centos6.3-64> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1547714827.5079.19.camel@Centos6.3-64> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9138 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=926 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1901170068 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 17, 2019 at 04:47:07PM +0800, Ching Huang wrote: > On Thu, 2019-01-17 at 10:59 +0300, Dan Carpenter wrote: > > On Thu, Jan 17, 2019 at 11:45:03AM +0800, Ching Huang wrote: > > > >From Ching Huang > > > > > > Fix suspend/resume of ACB_ADAPTER_TYPE_B part 2. > > > > > > > What does this look like from a user perspective? Does it fail every > > time or does it only fail sometimes? > > > > What's the bug exactly? > > > > There is no Fixes tag... > >From user's perspective, hibernate/resume are OK. > But following IO may cause 'isr get an illegal ccb command' in > log/messages sometime. > > You will need to resend with that information included in the commit message. > > > Signed-off-by: Ching Huang > > > --- > > > > > > diff --git a/drivers/scsi/arcmsr/arcmsr.h b/drivers/scsi/arcmsr/arcmsr.h > > > index a94c513..b98c632 100755 > > > --- a/drivers/scsi/arcmsr/arcmsr.h > > > +++ b/drivers/scsi/arcmsr/arcmsr.h > > > @@ -508,9 +508,9 @@ struct MessageUnit_A > > > struct MessageUnit_B > > > { > > > uint32_t post_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE]; > > > - uint32_t done_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE]; > > > + volatile uint32_t done_qbuffer[ARCMSR_MAX_HBB_POSTQUEUE]; > > > > There is a well known rule of thumb that when someone uses "volatile" > > in the kernel it means there is a locking problem... Is this __iomem or > > something? > The done_qbuffer was a command completion queue, it was an area written > by IO processor and read by device driver. So, ... I'm not totally positive I understand this sentence. I can find a bunch of places which read from this buffer, but I haven't immediately found which place writes to it. Can you give me a function name that I should read? > > > > > uint32_t postq_index; > > > - uint32_t doneq_index; > > > + volatile uint32_t doneq_index; The volatile here is not right. It's just normal memory. regards, dan carpenter