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=-5.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 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 86837C32792 for ; Thu, 3 Oct 2019 11:34:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 54C3120830 for ; Thu, 3 Oct 2019 11:34:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="qugWByDP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730229AbfJCLep (ORCPT ); Thu, 3 Oct 2019 07:34:45 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:42648 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730018AbfJCLep (ORCPT ); Thu, 3 Oct 2019 07:34:45 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x93BXvVO133419; Thu, 3 Oct 2019 11:34:41 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 : content-transfer-encoding : in-reply-to; s=corp-2019-08-05; bh=ER+a2BxvyuPvFP+5B1+t/eEBvhU2exoZo5NNX+TZSPo=; b=qugWByDP7h2kyZmosEsA//CzOArVNvhkCVGLxNlY1WOzTGzEUn7pSrcWWiIpvNZjCx9o OcjuayS1A/KLU9vIvKtBGF7nXiE2qqyCRyxGpEkBF1h0gSIDI2zyokb4TDfbhxakbPMq thhCTFx5LgGmQKGa+57K99TbnS+fLlOlaFpYkKr1l3TscksQiLmtAj3RnWrkzP2DyoW4 Isy6Ksevpvc8IlPN1HprJM0B5Ain9o53TNtczfzlHHg7PH4mh5DGe7t+xZOIf6firg+U snA6g3ezW8XbNS+G2kseHOCWQ0/lMhJ+KubLFhJfX692NrThnXslDcjKj6joCovu4gQZ eA== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2v9xxv3bm2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 03 Oct 2019 11:34:41 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x93BYMqu059837; Thu, 3 Oct 2019 11:34:40 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3020.oracle.com with ESMTP id 2vckyqmerm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 03 Oct 2019 11:34:40 +0000 Received: from abhmp0020.oracle.com (abhmp0020.oracle.com [141.146.116.26]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x93BYcG0006862; Thu, 3 Oct 2019 11:34:39 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 03 Oct 2019 04:34:38 -0700 Date: Thu, 3 Oct 2019 14:34:29 +0300 From: Dan Carpenter To: Valdis =?utf-8?Q?Kl=C4=93tnieks?= Cc: gregkh@linuxfoundation.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, Saiyam Doshi Subject: Re: [PATCH] drivers/staging/exfat - explain the fs_sync() issue in TODO Message-ID: <20191003113429.GS22609@kadam> References: <9837.1570042895@turing-police> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9837.1570042895@turing-police> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9398 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910030108 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9398 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default 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=8.0.1-1908290000 definitions=main-1910030108 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 02, 2019 at 03:01:35PM -0400, Valdis Klētnieks wrote: > We've seen several incorrect patches for fs_sync() calls in the exfat driver. > Add code to the TODO that explains this isn't just a delete code and refactor, > but that actual analysis of when the filesystem should be flushed to disk > needs to be done. > This doesn't help at all because no one can be expected to read it. Put a comment in the code which says something like: diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c index 229ecabe7a93..c1710d99875e 100644 --- a/drivers/staging/exfat/exfat_super.c +++ b/drivers/staging/exfat/exfat_super.c @@ -287,6 +287,13 @@ static DEFINE_SEMAPHORE(z_sem); static inline void fs_sync(struct super_block *sb, bool do_sync) { + /* + * Oct 2019: Please, do not delete this code or the callers. This + * code is obviously bogus and many of the callers are dead code, yes, + * but it may hold clues as to when syncing is required. Someone needs + * to go through and audit it really carefully. + * + */ if (do_sync) bdev_sync(sb); }