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=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 527F7C04AB5 for ; Mon, 3 Jun 2019 23:35:40 +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 D0DF1265AE for ; Mon, 3 Jun 2019 23:35:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0DF1265AE 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 45Hryd6n4PzDqVD for ; Tue, 4 Jun 2019 09:35:37 +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=tyreld@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 45HrxD3zKvzDq75 for ; Tue, 4 Jun 2019 09:34:24 +1000 (AEST) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x53NWl0r111800 for ; Mon, 3 Jun 2019 19:34:22 -0400 Received: from e13.ny.us.ibm.com (e13.ny.us.ibm.com [129.33.205.203]) by mx0a-001b2d01.pphosted.com with ESMTP id 2swcx4grpv-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 03 Jun 2019 19:34:22 -0400 Received: from localhost by e13.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, 4 Jun 2019 00:34:18 +0100 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x53NYHtf18546912 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 3 Jun 2019 23:34:17 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7DFEAAC05B; Mon, 3 Jun 2019 23:34:17 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 57642AC059; Mon, 3 Jun 2019 23:34:16 +0000 (GMT) Received: from oc6857751186.ibm.com (unknown [9.85.191.102]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP; Mon, 3 Jun 2019 23:34:16 +0000 (GMT) Subject: Re: [PATCH v2] scsi: ibmvscsi: Don't use rc uninitialized in ibmvscsi_do_work From: Tyrel Datwyler To: Nathan Chancellor , Tyrel Datwyler , "James E.J. Bottomley" , "Martin K. Petersen" References: <20190531185306.41290-1-natechancellor@gmail.com> <20190603221941.65432-1-natechancellor@gmail.com> <6fa1dd2e-676f-b12a-5bb6-e86f5c5628fa@linux.vnet.ibm.com> Date: Mon, 3 Jun 2019 16:34:15 -0700 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: <6fa1dd2e-676f-b12a-5bb6-e86f5c5628fa@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19060323-0064-0000-0000-000003E93CB8 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00011210; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000286; SDB=6.01212850; UDB=6.00637411; IPR=6.00993910; MB=3.00027171; MTD=3.00000008; XFM=3.00000015; UTC=2019-06-03 23:34:20 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19060323-0065-0000-0000-00003DBA2142 Message-Id: <8598d642-82e3-daad-a487-693208e13c90@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-03_19:, , 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-1906030158 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: clang-built-linux@googlegroups.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 06/03/2019 04:25 PM, Tyrel Datwyler wrote: > On 06/03/2019 03:19 PM, Nathan Chancellor wrote: >> clang warns: >> >> drivers/scsi/ibmvscsi/ibmvscsi.c:2126:7: warning: variable 'rc' is used >> uninitialized whenever switch case is taken [-Wsometimes-uninitialized] >> case IBMVSCSI_HOST_ACTION_NONE: >> ^~~~~~~~~~~~~~~~~~~~~~~~~ >> drivers/scsi/ibmvscsi/ibmvscsi.c:2151:6: note: uninitialized use occurs >> here >> if (rc) { >> ^~ >> >> Initialize rc to zero in the case statements that clang mentions so that >> the atomic_set and dev_err statement don't trigger for them. >> >> Fixes: 035a3c4046b5 ("scsi: ibmvscsi: redo driver work thread to use enum action states") >> Link: https://github.com/ClangBuiltLinux/linux/issues/502 >> Suggested-by: Michael Ellerman >> Signed-off-by: Nathan Chancellor > > Acked-by: Tyrel Datwyler > On second thought NACK. See my response to Michael earlier in the thread. I think this is the better solution: diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c index 727c31dc11a0..c3cf05dd8733 100644 --- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -2123,8 +2123,8 @@ static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata) spin_lock_irqsave(hostdata->host->host_lock, flags); switch (hostdata->action) { - case IBMVSCSI_HOST_ACTION_NONE: case IBMVSCSI_HOST_ACTION_UNBLOCK: + rc = 0; break; case IBMVSCSI_HOST_ACTION_RESET: spin_unlock_irqrestore(hostdata->host->host_lock, flags); @@ -2142,8 +2142,9 @@ static void ibmvscsi_do_work(struct ibmvscsi_host_data *hostdata) if (!rc) rc = ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0); break; + case IBMVSCSI_HOST_ACTION_NONE: default: - break; + return; } hostdata->action = IBMVSCSI_HOST_ACTION_NONE;