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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE570C433EF for ; Thu, 23 Jun 2022 07:55:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230412AbiFWHzq (ORCPT ); Thu, 23 Jun 2022 03:55:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230403AbiFWHzp (ORCPT ); Thu, 23 Jun 2022 03:55:45 -0400 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 983B14706A; Thu, 23 Jun 2022 00:55:44 -0700 (PDT) Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 25N73xpc004720; Thu, 23 Jun 2022 07:55:28 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : content-type : in-reply-to : mime-version; s=corp-2021-07-09; bh=ayceEkAS5JFTqEFviSVDv/09ZZGtqFDpagQCfbAVuo4=; b=O0ImFdIClkDCWE7V/xsZDwKBau6Z1+/OY4v7WDiEbcyiY11Xjo58LiyR78JY7+jFCogT ntEL4C8fJfBj9d9ruhDn5B5anxgLgnmFgP5BR4ddPzhn9+qDRPlI5Fv7qVZWvuhLE2GL lBpGGu5SQLoDq7c/JYSzi2YxldwORYAHE6PVwMZ0qGf98Lr1nLppkR66HLUKHSgKsd4D aNQwsUKpdVHfDMKQwq7bgo0ZB1R2pOxVJKYI+alvA13ME2zXDiJtY+dUgrQ7eyBoMoLG tvii1LUXueEM5Y8xq0wCbgQw/u6Pu1fzQNd+VsW6ixfDPemY5JRgV+qDXsnWj+TSryQX Vg== Received: from phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (phxpaimrmta01.appoci.oracle.com [138.1.114.2]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3gs54ctbf8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 23 Jun 2022 07:55:27 +0000 Received: from pps.filterd (phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com [127.0.0.1]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com (8.16.1.2/8.16.1.2) with SMTP id 25N7oZX5040912; Thu, 23 Jun 2022 07:55:26 GMT Received: from nam11-bn8-obe.outbound.protection.outlook.com (mail-bn8nam11lp2168.outbound.protection.outlook.com [104.47.58.168]) by phxpaimrmta01.imrmtpd1.prodappphxaev1.oraclevcn.com with ESMTP id 3gth8yb0c8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 23 Jun 2022 07:55:26 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=JRReWEyhnGzvdlZyRm2/5a/otlC/eyX2QZ1kdDsvAzgSxRcDlirN8tiiipIVZB8Exrn/V+kvNZAVO1zuIickhYLhm9bWnMJAL6PvEWAGriUyMR9ayotjRkkhCzzJLoNz6wAC/93JqghIM7GwGACEuzgdTxiqfrkALR//b1tP2toRSVzuET11+4/5+S4mvuuDl3VxvpLOw9EaRH6jMN70DiswsDAGWGRu62fKAWv7w9IgU+YlVLRx/HMkjfCrNMXUQLPGh1nZwlq+m5eqzvwuBSymYruXTLSvDgICrK+kEa13nPNn2Q+qc0FOlEN0DlyJkwr/wNqcKWXyMKWhHVLQJA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=ayceEkAS5JFTqEFviSVDv/09ZZGtqFDpagQCfbAVuo4=; b=lj+r/Y0mQqhIqjmfYCXnWfISUiWCPeQhk+YooaldXySx7jeCqtj8lOJvgS3v2kOb/gA2+p12MVb7TNk+1fND6N2pvf+6JfPc9M0JEfWAT1ZwXkfiTERKAMFxQRcjHa8zdd4hvLKd72ODOUQsqVBHiVGHpVLRqSO82TkANVStt2k10jDEwijhwFJ0X4cyco/XlDPRt/dPLWrpX+wNIw/wMR0k6w7Zc9yP+QLjz9riveF6KSRCkapGvOd5guab5842Mpbf029ZB7pU9514AtdCQi3M/J/KLS4I/numF54uiULpU16GtSe9TzXrPn0WlrcecLw7dK82uzbmvrYcO9XWsg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=ayceEkAS5JFTqEFviSVDv/09ZZGtqFDpagQCfbAVuo4=; b=jxDIRyQM//aNyIjXjW55/DrrsoLtzot8KDqbvGnMa1lfEQoEdiCyVK9EL9hXCnO9rBktUGjSrZv36dszDXh9MrfG28KuoBeL6RuuYLp/WWkOrqGBIPii2glZ6gm2kq3gIdmLeTYSUWW911G4cOlDz3OnanZaEVL/eu4jqiTLDjk= Received: from MWHPR1001MB2365.namprd10.prod.outlook.com (2603:10b6:301:2d::28) by CY4PR1001MB2102.namprd10.prod.outlook.com (2603:10b6:910:44::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5353.14; Thu, 23 Jun 2022 07:55:24 +0000 Received: from MWHPR1001MB2365.namprd10.prod.outlook.com ([fe80::5020:9b82:5917:40b]) by MWHPR1001MB2365.namprd10.prod.outlook.com ([fe80::5020:9b82:5917:40b%6]) with mapi id 15.20.5373.015; Thu, 23 Jun 2022 07:55:24 +0000 Date: Thu, 23 Jun 2022 10:55:03 +0300 From: Dan Carpenter To: Neal Liu Cc: Felipe Balbi , Greg Kroah-Hartman , Joel Stanley , Andrew Jeffery , "linux-aspeed@lists.ozlabs.org" , "linux-usb@vger.kernel.org" , "kernel-janitors@vger.kernel.org" Subject: Re: [PATCH] usb: gadget: aspeed_udc: fix handling of tx_len == 0 Message-ID: <20220623075503.GC11460@kadam> References: <20220623064320.GN16517@kadam> <20220623072216.GQ16517@kadam> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-ClientProxiedBy: JNXP275CA0021.ZAFP275.PROD.OUTLOOK.COM (2603:1086:0:19::33) To MWHPR1001MB2365.namprd10.prod.outlook.com (2603:10b6:301:2d::28) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: e83393f8-3c79-4222-59e2-08da54edba90 X-MS-TrafficTypeDiagnostic: CY4PR1001MB2102:EE_ X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:MWHPR1001MB2365.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(7916004)(346002)(376002)(366004)(136003)(396003)(39860400002)(9686003)(6486002)(6506007)(6512007)(6666004)(2906002)(52116002)(66476007)(8676002)(41300700001)(38100700002)(33716001)(26005)(66946007)(316002)(54906003)(66556008)(478600001)(86362001)(1076003)(186003)(6916009)(83380400001)(33656002)(5660300002)(4326008)(38350700002)(44832011)(8936002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Tisxnz0t/FOvZwJBmeWKCrJ0WXjUYwsJPmbPdiYgRl5DL2hPh/preM5YpvPK?= =?us-ascii?Q?rQL2ZlerXp1sSILDy9Z1vV0WQ1/a4OAlCV0NWzWw5sq7O5li971rqh/3qKV4?= =?us-ascii?Q?qcyxRY72bCmpgxM8OoEf/Sk8RfWO8RE/eDj2gfegtm0EU7T6CULU3PPeaZJT?= =?us-ascii?Q?cnad90/7CwT2tPCgd056yrDyKbTMPRLCSFYgEYsqfksVF/g5Uh0Di3euSsWQ?= =?us-ascii?Q?fiLb+yxCBQOVydC3RPky38bbT4HtJWp2aOznGoXPtNCQ5HIaK7eoc80el8+7?= =?us-ascii?Q?eQ6dk9l+PzTR+Oind5PDN9a2ek22nrN5Kam7d16223GB2xRFW5gClfLmgYFh?= =?us-ascii?Q?tmvbLYSrB4uj23rRVgx3UzBdkfsjjw5DAyDpbwukclNMNKNTkJZqmscNYITj?= =?us-ascii?Q?GSiQy19JHRePnYLbEOVaaqzqMCtVA/+MHQH6ZdKETiRjx00rPjscA21RWinN?= =?us-ascii?Q?swy9DL2V78tjrtgY2nrubEWhpKlmlPfqDZB6jTO8Bao4QMH73eb3P2Bz5qkJ?= =?us-ascii?Q?gxNApQ7KlR+u1Fby+EAHKMYdet2Ma2IeGZVp+c0vx+uEXpR/8yccRlcT86O5?= =?us-ascii?Q?S/KD+mkYfZ231WfJm6qpqtC1GvP7jwGUfOik9cpV+GR1muoqjmUHvYWBO/AY?= =?us-ascii?Q?RxiZSPIZw8QuiiLH0SPX1G4MUQFJ751/eZSN90Nzs6hYA2a+qHfUH4BiCxls?= =?us-ascii?Q?Jh2o6L9zJL2xKpUpOUojklhrh2LgPDWHnQUKFMZixfAwzQW194CY7AuX8OC+?= =?us-ascii?Q?PQymQ5N7RMRKkHpF459mCvQ2oyM82SexDckhKFXHQY1l4NZg009/9rVIYDzI?= =?us-ascii?Q?YFz2uP6C0j0sdveMbIPsVPtg9vSQSU0nZmsw3mt+8aFlDbB0VzQ+clAADTOm?= =?us-ascii?Q?HFs7+I2FZuf0VFLLJiH9dEvIrjnlcVjc/2/P1YmCBHFE0+yqFXwDJNtsCEgX?= =?us-ascii?Q?kTEbANy3FgnX3tsWcUIU5OvU+k9vZSDFcwrne0X1YAy29EZfwAUDPkgyJn0Y?= =?us-ascii?Q?CKKi+lfFJGR5SfZaUEahCY8CLWzINZlCEjIWwmnZHBJ/FMDQ3f/1fIaRy75+?= =?us-ascii?Q?JJYDSD6kBS7VATmhvZEm4mE0AWyngscpQ4nKZbt8pjFlDqVBqlJDHyB4MDPj?= =?us-ascii?Q?nDDDMe3OmX6e1LxONNjpul7Hrk690UFKNr2MSuZeaG4Bmuuso0RX9/PkdxSD?= =?us-ascii?Q?UVFWM6T/Y/SMjJp9lur6lFLSw8sLSTITSr3lDz88w/Pn0iTD6WTc0qOlLKKH?= =?us-ascii?Q?nU2bsxI0NaXQPbf3US5KYr9PVYr3iYkvciXSV6J/A5n6qSalREeDQQDegeHw?= =?us-ascii?Q?m214OyqLHtCkriDu1ccyNlMyDANONnv3HR2Bv5RhxX+JBitRZR7Am2ghI6DB?= =?us-ascii?Q?vuXO+/ScBwRZjRag84b5y1oghY2l3cRWPhzZ6buzwfr78l7HMCnPbv9BT+jo?= =?us-ascii?Q?8M1wVtVRAebAr470udU/1eKvmzOVhnlT/nKPV2cWra7EjI66P4oQmPsXdLmh?= =?us-ascii?Q?A9JVXeIj/H8kVYJ5lLqdtfvOuP7x0Hv+scq8u9Te1QNMJHqhbbyhIGw2MZDZ?= =?us-ascii?Q?cuSwljSOYLiiLP1AQkWCSjp04W8wxboP4DCdJBeE+GFC9vg1TCkmKyxJXRuf?= =?us-ascii?Q?rQ=3D=3D?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: e83393f8-3c79-4222-59e2-08da54edba90 X-MS-Exchange-CrossTenant-AuthSource: MWHPR1001MB2365.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jun 2022 07:55:24.5350 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: b7pBY/EfGMilbuC5cn2zj+3RjkM04U2nYUBWo8vMLkG6GzR9+OmbqIe9joo34hi2yL6Sh9l3LyzH+3Z/BKrI5hloO4bPbBaEH6HKcP1EGn4= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR1001MB2102 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.517,18.0.883 definitions=2022-06-23_03:2022-06-22,2022-06-23 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 malwarescore=0 mlxscore=0 phishscore=0 adultscore=0 suspectscore=0 mlxlogscore=677 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2204290000 definitions=main-2206230030 X-Proofpoint-GUID: 0XokYetPWwnTC8d5HIjpcsdnxI85QFfj X-Proofpoint-ORIG-GUID: 0XokYetPWwnTC8d5HIjpcsdnxI85QFfj Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Thu, Jun 23, 2022 at 07:52:28AM +0000, Neal Liu wrote: > > On Thu, Jun 23, 2022 at 09:43:20AM +0300, Dan Carpenter wrote: > > > On Thu, Jun 23, 2022 at 01:41:49AM +0000, Neal Liu wrote: > > > > > The bug is that we should still enter this loop if "tx_len" is zero. > > > > > > > > > > After adding the "last" variable, then the "chunk >= 0" condition > > > > > is no longer required but I left it for readability. > > > > > > > > > > > > > Use either "chunk >=0" or "last". > > > > I think the former is more simpler. > > > > > > chunk >= 0 doesn't work. last works but I think this way is more > > > readable. > > > > Fine, I can remove the chunk >= 0. But you can see why your idea of > > removing the "last" doesn't work, right? I mean maybe it does work and > > there was a bug in the original code? Could you please look at that so we're > > for sure writing correct code? > > > > Why removing the "last" doesn't work? If "chunk == 0", it would go through while loop once, and chunk will be negative (chunk -= ep->chunk_max). > chunk -= ep->chunk_max could set chunk to zero. regards, dan carpenter