From patchwork Thu Jun 1 02:36:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 9758613 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 EDDC0602F0 for ; Thu, 1 Jun 2017 02:35:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DE5C327569 for ; Thu, 1 Jun 2017 02:35:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D018727FC0; Thu, 1 Jun 2017 02:35:11 +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=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_HI autolearn=unavailable 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 82F4727569 for ; Thu, 1 Jun 2017 02:35:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751105AbdFACeo (ORCPT ); Wed, 31 May 2017 22:34:44 -0400 Received: from m12-14.163.com ([220.181.12.14]:47954 "EHLO m12-14.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751052AbdFACen (ORCPT ); Wed, 31 May 2017 22:34:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=5Sei9z/WxfTc94f9nU 3RHV9Ztx0CA7ugF0NT6jWPjdg=; b=dG9Sio3D47UD3CW2z+LnkGshRp4TO4521T uXJ44TeS9nRoU2BylhYpM+YlOdJoK5dKiAr6bhHmDklQZP25bNjsceCoMYf69DvN RrvfgkXPghDeOjXKwGNJO3OmMIpp/Atxit68y/v4zRaTTixEIlZ+3oMzIpSJg34O GvMffLuKw= Received: from bai-oslab.tsinghua.edu.cn (unknown [166.111.70.19]) by smtp10 (Coremail) with SMTP id DsCowADnJWIWfS9Z9spOIQ--.19495S2; Thu, 01 Jun 2017 10:34:01 +0800 (CST) From: Jia-Ju Bai To: pizza@shaftnet.org, kvalo@codeaurora.org Cc: linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] cw1200: Fix a sleep-in-atomic bug in cw1200_tx_confirm_cb and cw1200_cqm_bssloss_sm Date: Thu, 1 Jun 2017 10:36:14 +0800 Message-Id: <1496284574-11056-1-git-send-email-baijiaju1990@163.com> X-Mailer: git-send-email 1.7.9.5 X-CM-TRANSID: DsCowADnJWIWfS9Z9spOIQ--.19495S2 X-Coremail-Antispam: 1Uf129KBjvdXoW7XryfCw18tFy5ZryDCFyfJFb_yoWkArbEkF 9agFy0qw4rAwnIvw1rurW3Zr4Ik3Z5Z3Wxuw4xKFZxCayDXFWUXa93AFW5Jrn8uF4kuFZx Gw1DWw1rArnFgjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IUjiIDDUUUUU== X-Originating-IP: [166.111.70.19] X-CM-SenderInfo: xedlyx5dmximizq6il2tof0z/1tbiGBnpelXlZ0cDUwAAsS 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 The driver may sleep under a spin lock, and the function call path is: cw1200_tx_confirm_cb (acquire the lock by spin_lock) __cw1200_cqm_bssloss_sm cancel_work_sync --> may sleep cw1200_cqm_bssloss_sm __cw1200_cqm_bssloss_sm cancel_work_sync --> may sleep To fix it, the lock is released before cancel_work_sync, and the lock is acquired again after this function. Signed-off-by: Jia-Ju Bai --- drivers/net/wireless/st/cw1200/sta.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/st/cw1200/sta.c b/drivers/net/wireless/st/cw1200/sta.c index a522248..d5f7698 100644 --- a/drivers/net/wireless/st/cw1200/sta.c +++ b/drivers/net/wireless/st/cw1200/sta.c @@ -154,7 +154,9 @@ void __cw1200_cqm_bssloss_sm(struct cw1200_common *priv, int tx = 0; priv->delayed_link_loss = 0; + spin_unlock(&priv->bss_loss_lock); cancel_work_sync(&priv->bss_params_work); + spin_lock(&priv->bss_loss_lock); pr_debug("[STA] CQM BSSLOSS_SM: state: %d init %d good %d bad: %d txlock: %d uj: %d\n", priv->bss_loss_state,