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=-8.3 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_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_SANE_1 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 7AF08C433DF for ; Wed, 17 Jun 2020 11:13:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 580D220CC7 for ; Wed, 17 Jun 2020 11:13:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="A2dLbOXc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726928AbgFQLNw (ORCPT ); Wed, 17 Jun 2020 07:13:52 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:33854 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726899AbgFQLNv (ORCPT ); Wed, 17 Jun 2020 07:13:51 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 05HBD7dx118817; Wed, 17 Jun 2020 11:13:39 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-2020-01-29; bh=cuNGorMCGRL2h1N6XRNC1GY6mItog4OtrSLpqxId5mo=; b=A2dLbOXcLXjWH4ngUp9sSdKtQGnN8HjUtHi+IMOBdN/OfpbMrsLVjiYgts+NbLwfFU+r veJcPV3EuoS9iaVbn30dR8uAufSE8s0GTKYgVmPUqpMz3rXFGjtcQpvVWOrMjCuUp/uY CpAKRY1wUnhDkXiYtQGMk7YhhxYgRGJom65xHxZxFcFlmt2N/V2Mn8egOo6a5HceycSl Lwj2SxwFKhZtrdV+O3J7unD1OM/g8vU7A3bxLPkqHeoBRHpvyZQJ/JlHi0QdbI+wib5p r3z3270/Pb3GfMF18+aOJlOOZbMo1dYeC9PK0DXJAn2MUZQUQApWf4aadd3YLw48Xv6B Vw== Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by aserp2120.oracle.com with ESMTP id 31qecks591-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 17 Jun 2020 11:13:39 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 05HBD8Ds161596; Wed, 17 Jun 2020 11:13:38 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 31q66nr3r8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 17 Jun 2020 11:13:38 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 05HBDUql031357; Wed, 17 Jun 2020 11:13:30 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 17 Jun 2020 04:13:29 -0700 Date: Wed, 17 Jun 2020 14:13:22 +0300 From: Dan Carpenter To: Souptick Joarder Cc: gregkh@linuxfoundation.org, jane.pnx9@gmail.com, pakki001@umn.edu, ldufour@linux.ibm.com, harshjain32@gmail.com, simon@nikanor.nu, walken@google.com, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, John Hubbard , Bharath Vedartham Subject: Re: [PATCH 1/4] staging: kpc2000: Unpin partial pinned pages Message-ID: <20200617111321.GP4282@kadam> References: <1592360843-3440-1-git-send-email-jrdr.linux@gmail.com> <1592360843-3440-2-git-send-email-jrdr.linux@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1592360843-3440-2-git-send-email-jrdr.linux@gmail.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9654 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 mlxlogscore=999 bulkscore=0 adultscore=0 phishscore=0 suspectscore=2 mlxscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006170088 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9654 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 cotscore=-2147483648 malwarescore=0 clxscore=1011 adultscore=0 suspectscore=2 spamscore=0 lowpriorityscore=0 mlxlogscore=999 priorityscore=1501 bulkscore=0 phishscore=0 mlxscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006170088 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 17, 2020 at 07:57:20AM +0530, Souptick Joarder wrote: > There is a bug, when get_user_pages() failed but partially pinned > pages are not unpinned. Fixed it. > > Also, int is more appropriate type for rv. Changed it. > > Signed-off-by: Souptick Joarder > Cc: John Hubbard > Cc: Bharath Vedartham > Cc: Dan Carpenter > --- > drivers/staging/kpc2000/kpc_dma/fileops.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/staging/kpc2000/kpc_dma/fileops.c b/drivers/staging/kpc2000/kpc_dma/fileops.c > index 8975346..b136353 100644 > --- a/drivers/staging/kpc2000/kpc_dma/fileops.c > +++ b/drivers/staging/kpc2000/kpc_dma/fileops.c > @@ -35,7 +35,7 @@ static int kpc_dma_transfer(struct dev_private_data *priv, > unsigned long iov_base, size_t iov_len) > { > unsigned int i = 0; > - long rv = 0; > + int rv = 0; > struct kpc_dma_device *ldev; > struct aio_cb_data *acd; > DECLARE_COMPLETION_ONSTACK(done); > @@ -193,6 +193,10 @@ static int kpc_dma_transfer(struct dev_private_data *priv, > put_page(acd->user_pages[i]); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > err_get_user_pages: > + if (rv > 0) { > + for (i = 0; i < rv; i++) > + put_pages(acd->user_pages[i]) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > + } This isn't a complete fix. "rv" is the negative error code but here we are returning a positive value on this path. Also it's ugly to have same put_page() loop repeated twice. It would be better to write it like this: rv = get_user_pages(iov_base, acd->page_count, FOLL_TOUCH | FOLL_WRITE | FOLL_GET, acd->user_pages, NULL); mmap_read_unlock(current->mm); /* release the semaphore */ if (rv < 0) goto free_pages; if (rv != acd->page_count) { acd->page_count = rv; rv = -EFAULT; goto put_pages; } ... put_pages: for (i = 0 ; i < acd->page_count ; i++) put_pages(acd->user_pages[i]); free_pages: kfree(acd->user_pages); regards, dan carpenter