From patchwork Fri Jun 1 10:41:20 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ganapathi Bhat X-Patchwork-Id: 10442951 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A8452602BC for ; Fri, 1 Jun 2018 10:41:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9A5A128E85 for ; Fri, 1 Jun 2018 10:41:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8E58228E8D; Fri, 1 Jun 2018 10:41:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2DD9A28E85 for ; Fri, 1 Jun 2018 10:41:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751685AbeFAKlj (ORCPT ); Fri, 1 Jun 2018 06:41:39 -0400 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:51086 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751346AbeFAKlh (ORCPT ); Fri, 1 Jun 2018 06:41:37 -0400 Received: from pps.filterd (m0045851.ppops.net [127.0.0.1]) by mx0b-0016f401.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w51Adw0G009929; Fri, 1 Jun 2018 03:41:35 -0700 Received: from sc-exch02.marvell.com ([199.233.58.182]) by mx0b-0016f401.pphosted.com with ESMTP id 2j9ewf12wq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Fri, 01 Jun 2018 03:41:35 -0700 Received: from SC-EXCH03.marvell.com (10.93.176.83) by SC-EXCH02.marvell.com (10.93.176.82) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Fri, 1 Jun 2018 03:41:24 -0700 Received: from maili.marvell.com (10.93.176.43) by SC-EXCH03.marvell.com (10.93.176.83) with Microsoft SMTP Server id 15.0.1210.3 via Frontend Transport; Fri, 1 Jun 2018 03:41:24 -0700 Received: from localhost.marvell.com (gbhat-thinkpad-t430.marvell.com [10.31.130.245]) by maili.marvell.com (Postfix) with ESMTP id A0C7D3F7040; Fri, 1 Jun 2018 03:41:24 -0700 (PDT) Received: from localhost.marvell.com (localhost [127.0.0.1]) by localhost.marvell.com (8.14.4/8.14.4/Debian-4.1ubuntu1) with ESMTP id w51AfNEx005180; Fri, 1 Jun 2018 16:11:23 +0530 Received: (from root@localhost) by localhost.marvell.com (8.14.4/8.14.4/Submit) id w51AfMHp004723; Fri, 1 Jun 2018 16:11:22 +0530 From: Ganapathi Bhat To: CC: Brian Norris , Cathy Luo , Xinming Hu , Zhiyuan Yang , James Cao , Mangesh Malusare , Ganapathi Bhat Subject: [PATCH 2/2] mwifiex: handle race during mwifiex_usb_disconnect Date: Fri, 1 Jun 2018 16:11:20 +0530 Message-ID: <1527849680-31445-2-git-send-email-gbhat@marvell.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1527849680-31445-1-git-send-email-gbhat@marvell.com> References: <1527849680-31445-1-git-send-email-gbhat@marvell.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-06-01_06:, , signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=948 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1805220000 definitions=main-1806010123 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Race condition is observed during rmmod of mwifiex_usb: 1. The rmmod thread will call mwifiex_usb_disconnect(), download SHUTDOWN command and do wait_event_interruptible_timeout(), waiting for response. 2. The main thread will handle the response and will do a wake_up_interruptible(), unblocking rmmod thread. 3. On getting unblocked, rmmod thread will make rx_cmd.urb = NULL in mwifiex_usb_free(). 4. The main thread will try to resubmit rx_cmd.urb in mwifiex_usb_submit_rx_urb(), which is NULL. To fix this, move mwifiex_usb_free() from mwifiex_usb_disconnect to mwifiex_unregister_dev(). Function mwifiex_unregister_dev() is called after flushing the command and RX work queues. Signed-off-by: Brian Norris Signed-off-by: Ganapathi Bhat Reviewed-by: Brian Norris --- drivers/net/wireless/marvell/mwifiex/usb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/marvell/mwifiex/usb.c b/drivers/net/wireless/marvell/mwifiex/usb.c index bc475b8..88f4c89 100644 --- a/drivers/net/wireless/marvell/mwifiex/usb.c +++ b/drivers/net/wireless/marvell/mwifiex/usb.c @@ -644,8 +644,6 @@ static void mwifiex_usb_disconnect(struct usb_interface *intf) MWIFIEX_FUNC_SHUTDOWN); } - mwifiex_usb_free(card); - mwifiex_dbg(adapter, FATAL, "%s: removing card\n", __func__); mwifiex_remove_card(adapter); @@ -1353,6 +1351,8 @@ static void mwifiex_unregister_dev(struct mwifiex_adapter *adapter) { struct usb_card_rec *card = (struct usb_card_rec *)adapter->card; + mwifiex_usb_free(card); + mwifiex_usb_cleanup_tx_aggr(adapter); card->adapter = NULL;