From patchwork Tue Oct 8 02:22:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Kang Yang X-Patchwork-Id: 833911 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9939E282EE for ; Tue, 8 Oct 2024 02:23:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728354214; cv=none; b=DN7ch//gzCVe6vNBBK/9MCb/yNOTLOtMcE4VWj8mxyLmQBXbxLcuItXJqtjsw2EKm9sL56ajZbJFSkpd2KEEq4e2YXnl2mi+MSvcMKegteLXWuXfqjWa9y5U3ZHkXyOFVh06gHFgKk5s+3Txn0d/vJgYBCm9bq9h/8uAUkk7qps= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728354214; c=relaxed/simple; bh=Z79wgkID6ADbkN4HBiuoucCUmTsPjdv9bjOqsyntf9Q=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=gWXvHN9JvuRo/hZE7S64qg9w/Lqlin3BHY1vciUdob0ltuerANbVXFvfswRdRBEvggn/B5Vw2wK0rgEAzvtfWws6t65iIWs+d+pH6SRuV3OS2ql2mNOi6cWKVmdfTMTLFtYVJ4YptN2oYVB/4xO26dQre6oPqAJ034OVTIQufYE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=UsWISEQl; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="UsWISEQl" Received: from pps.filterd (m0279866.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 497DntBi004324; Tue, 8 Oct 2024 02:23:27 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-transfer-encoding:content-type:date:from:message-id :mime-version:subject:to; s=qcppdkim1; bh=fRSwEjQxOoKZo6ILpSl0A4 gJ10LQDRCdbjQTEWIWETA=; b=UsWISEQloku8h8kxnh+74qT2AfyWIbvip3ZzUM F+GfHQNlZN/lBqe3tfHec8iLd+8cnQalyGCnPMqKEwHcmxxqxl1TwVLvKW2cFeNq Zr9oaO7YHJlJBhT+A2tLuo2K/Mvd6697e22HA/3iUKHBEk9EDvt03Xtxep0QmsWq ofryZAdJYBuRdYxDhHXsV86M/EiZTtCwOdhUT8XSwo5KOzVEWX4DGkRvS6NjvO7i FBxgziO28NY9JLyul27oZv9hO4zW+V/3DNthW92hxZzjVNITprBw5uOW5ReLfbmT GgW7YSPzHmAbAP1DYu0jSWNtyQ/KnJ0Ugf0jRzXHhVgDojkw== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 422xv6wx49-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 08 Oct 2024 02:23:27 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA04.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 4982NR12026733 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 8 Oct 2024 02:23:27 GMT Received: from kangyang.ap.qualcomm.com (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Mon, 7 Oct 2024 19:23:25 -0700 From: Kang Yang To: CC: , Subject: [PATCH] wifi: ath10k: avoid NULL pointer error during sdio remove Date: Tue, 8 Oct 2024 10:22:46 +0800 Message-ID: <20241008022246.1010-1-quic_kangyang@quicinc.com> X-Mailer: git-send-email 2.34.1.windows.1 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: QioENoBwM0aR2ND6KbjZR1wfSGzxd-NC X-Proofpoint-GUID: QioENoBwM0aR2ND6KbjZR1wfSGzxd-NC X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.60.29 definitions=2024-09-06_09,2024-09-06_01,2024-09-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 priorityscore=1501 impostorscore=0 adultscore=0 lowpriorityscore=0 mlxlogscore=992 mlxscore=0 bulkscore=0 phishscore=0 malwarescore=0 spamscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410080013 When running 'rmmod ath10k', ath10k_sdio_remove() will free sdio workqueue by destroy_workqueue(). But if CONFIG_INIT_ON_FREE_DEFAULT_ON is set to yes, kernel panic will happen: Call trace: destroy_workqueue+0x1c/0x258 ath10k_sdio_remove+0x84/0x94 sdio_bus_remove+0x50/0x16c device_release_driver_internal+0x188/0x25c device_driver_detach+0x20/0x2c This is because during 'rmmod ath10k', ath10k_sdio_remove() will call ath10k_core_destroy() before destroy_workqueue(). wiphy_dev_release() will finally be called in ath10k_core_destroy(). This function will free struct cfg80211_registered_device *rdev and all its members, including wiphy, dev and the pointer of sdio workqueue. Then the pointer of sdio workqueue will be set to NULL due to CONFIG_INIT_ON_FREE_DEFAULT_ON. After device release, destroy_workqueue() will use NULL pointer then the kernel panic happen. Call trace: ath10k_sdio_remove ->ath10k_core_unregister …… ->ath10k_core_stop ->ath10k_hif_stop ->ath10k_sdio_irq_disable ->ath10k_hif_power_down ->del_timer_sync(&ar_sdio->sleep_timer) ->ath10k_core_destroy ->ath10k_mac_destroy ->ieee80211_free_hw ->wiphy_free …… ->wiphy_dev_release ->destroy_workqueue Need to call destroy_workqueue() before ath10k_core_destroy(), free the work queue buffer first and then free pointer of work queue by ath10k_core_destroy(). This order matches the error path order in ath10k_sdio_probe(). No work will be queued on sdio workqueue between it is destroyed and ath10k_core_destroy() is called. Based on the call_stack above, the reason is: Only ath10k_sdio_sleep_timer_handler(), ath10k_sdio_hif_tx_sg() and ath10k_sdio_irq_disable() will queue work on sdio workqueue. Sleep timer will be deleted before ath10k_core_destroy() in ath10k_hif_power_down(). ath10k_sdio_irq_disable() only be called in ath10k_hif_stop(). ath10k_core_unregister() will call ath10k_hif_power_down() to stop hif bus, so ath10k_sdio_hif_tx_sg() won't be called anymore. Tested-on: QCA6174 hw3.2 SDIO WLAN.RMH.4.4.1-00189 Signed-off-by: Kang Yang Tested-by: David Ruth Reviewed-by: David Ruth --- drivers/net/wireless/ath/ath10k/sdio.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c index 08a6f36a6be9..6805357ee29e 100644 --- a/drivers/net/wireless/ath/ath10k/sdio.c +++ b/drivers/net/wireless/ath/ath10k/sdio.c @@ -3,7 +3,7 @@ * Copyright (c) 2004-2011 Atheros Communications Inc. * Copyright (c) 2011-2012,2017 Qualcomm Atheros, Inc. * Copyright (c) 2016-2017 Erik Stromdahl - * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. + * Copyright (c) 2022-2024 Qualcomm Innovation Center, Inc. All rights reserved. */ #include @@ -2648,9 +2648,9 @@ static void ath10k_sdio_remove(struct sdio_func *func) netif_napi_del(&ar->napi); - ath10k_core_destroy(ar); - destroy_workqueue(ar_sdio->workqueue); + + ath10k_core_destroy(ar); } static const struct sdio_device_id ath10k_sdio_devices[] = {