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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_GIT 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 7168AC28EBD for ; Sun, 9 Jun 2019 17:10:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 479FC205F4 for ; Sun, 9 Jun 2019 17:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560100235; bh=4tmexyyDg5YjBmU1leTavXAAKwyF5zlK9bLrbH/HVPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rNFq9X6l3fJ6UCvFgWrinAC0zZbfkrdNWOacPfUis9oiVlI4ROlVq16gqHD/kg9B4 Gy9SKB1g4NlUZJcrJ9/GaqAU/JUe1kU8LVLOiHF8KwKGSKnHV8Ada3dYHM/EUWzJR+ OwrJQpyXJJpaoUDsfYvM/SI8u8t7C1XZVUtRe0uU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389083AbfFIRKe (ORCPT ); Sun, 9 Jun 2019 13:10:34 -0400 Received: from mail.kernel.org ([198.145.29.99]:40588 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388265AbfFIRCg (ORCPT ); Sun, 9 Jun 2019 13:02:36 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 07F48206C3; Sun, 9 Jun 2019 17:02:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560099755; bh=4tmexyyDg5YjBmU1leTavXAAKwyF5zlK9bLrbH/HVPI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ziaxUxec4V+FJmUGQP8K/i/Ero49zEJio6bzKlkJWuqfXMnOzjdJUW/7irNRqkON/ m+SHDhJpo6dDMjVKO7VN0N6LZfe3XW3zjwUbT7vxoUrexQFqJx6Txp+WUkQAjE6yos deqSFRbEp3XnmwRPtpd9AIf2rY9Msl/Wx2KblGZ8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Piotr Figiel , Kalle Valo , Sasha Levin Subject: [PATCH 4.4 155/241] brcmfmac: fix race during disconnect when USB completion is in progress Date: Sun, 9 Jun 2019 18:41:37 +0200 Message-Id: <20190609164152.244530252@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164147.729157653@linuxfoundation.org> References: <20190609164147.729157653@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit db3b9e2e1d58080d0754bdf9293dabf8c6491b67 ] It was observed that rarely during USB disconnect happening shortly after connect (before full initialization completes) usb_hub_wq would wait forever for the dev_init_lock to be unlocked. dev_init_lock would remain locked though because of infinite wait during usb_kill_urb: [ 2730.656472] kworker/0:2 D 0 260 2 0x00000000 [ 2730.660700] Workqueue: events request_firmware_work_func [ 2730.664807] [<809dca20>] (__schedule) from [<809dd164>] (schedule+0x4c/0xac) [ 2730.670587] [<809dd164>] (schedule) from [<8069af44>] (usb_kill_urb+0xdc/0x114) [ 2730.676815] [<8069af44>] (usb_kill_urb) from [<7f258b50>] (brcmf_usb_free_q+0x34/0xa8 [brcmfmac]) [ 2730.684833] [<7f258b50>] (brcmf_usb_free_q [brcmfmac]) from [<7f2517d4>] (brcmf_detach+0xa0/0xb8 [brcmfmac]) [ 2730.693557] [<7f2517d4>] (brcmf_detach [brcmfmac]) from [<7f251a34>] (brcmf_attach+0xac/0x3d8 [brcmfmac]) [ 2730.702094] [<7f251a34>] (brcmf_attach [brcmfmac]) from [<7f2587ac>] (brcmf_usb_probe_phase2+0x468/0x4a0 [brcmfmac]) [ 2730.711601] [<7f2587ac>] (brcmf_usb_probe_phase2 [brcmfmac]) from [<7f252888>] (brcmf_fw_request_done+0x194/0x220 [brcmfmac]) [ 2730.721795] [<7f252888>] (brcmf_fw_request_done [brcmfmac]) from [<805748e4>] (request_firmware_work_func+0x4c/0x88) [ 2730.731125] [<805748e4>] (request_firmware_work_func) from [<80141474>] (process_one_work+0x228/0x808) [ 2730.739223] [<80141474>] (process_one_work) from [<80141a80>] (worker_thread+0x2c/0x564) [ 2730.746105] [<80141a80>] (worker_thread) from [<80147bcc>] (kthread+0x13c/0x16c) [ 2730.752227] [<80147bcc>] (kthread) from [<801010b4>] (ret_from_fork+0x14/0x20) [ 2733.099695] kworker/0:3 D 0 1065 2 0x00000000 [ 2733.103926] Workqueue: usb_hub_wq hub_event [ 2733.106914] [<809dca20>] (__schedule) from [<809dd164>] (schedule+0x4c/0xac) [ 2733.112693] [<809dd164>] (schedule) from [<809e2a8c>] (schedule_timeout+0x214/0x3e4) [ 2733.119621] [<809e2a8c>] (schedule_timeout) from [<809dde2c>] (wait_for_common+0xc4/0x1c0) [ 2733.126810] [<809dde2c>] (wait_for_common) from [<7f258d00>] (brcmf_usb_disconnect+0x1c/0x4c [brcmfmac]) [ 2733.135206] [<7f258d00>] (brcmf_usb_disconnect [brcmfmac]) from [<8069e0c8>] (usb_unbind_interface+0x5c/0x1e4) [ 2733.143943] [<8069e0c8>] (usb_unbind_interface) from [<8056d3e8>] (device_release_driver_internal+0x164/0x1fc) [ 2733.152769] [<8056d3e8>] (device_release_driver_internal) from [<8056c078>] (bus_remove_device+0xd0/0xfc) [ 2733.161138] [<8056c078>] (bus_remove_device) from [<8056977c>] (device_del+0x11c/0x310) [ 2733.167939] [<8056977c>] (device_del) from [<8069cba8>] (usb_disable_device+0xa0/0x1cc) [ 2733.174743] [<8069cba8>] (usb_disable_device) from [<8069507c>] (usb_disconnect+0x74/0x1dc) [ 2733.181823] [<8069507c>] (usb_disconnect) from [<80695e88>] (hub_event+0x478/0xf88) [ 2733.188278] [<80695e88>] (hub_event) from [<80141474>] (process_one_work+0x228/0x808) [ 2733.194905] [<80141474>] (process_one_work) from [<80141a80>] (worker_thread+0x2c/0x564) [ 2733.201724] [<80141a80>] (worker_thread) from [<80147bcc>] (kthread+0x13c/0x16c) [ 2733.207913] [<80147bcc>] (kthread) from [<801010b4>] (ret_from_fork+0x14/0x20) It was traced down to a case where usb_kill_urb would be called on an URB structure containing more or less random data, including large number in its use_count. During the debugging it appeared that in brcmf_usb_free_q() the traversal over URBs' lists is not synchronized with operations on those lists in brcmf_usb_rx_complete() leading to handling brcmf_usbdev_info structure (holding lists' head) as lists' element and in result causing above problem. Fix it by walking through all URBs during brcmf_cancel_all_urbs using the arrays of requests instead of linked lists. Signed-off-by: Piotr Figiel Signed-off-by: Kalle Valo Signed-off-by: Sasha Levin --- drivers/net/wireless/brcm80211/brcmfmac/usb.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/brcm80211/brcmfmac/usb.c b/drivers/net/wireless/brcm80211/brcmfmac/usb.c index 32b7b8a8f80c6..8a7da04a9ed4b 100644 --- a/drivers/net/wireless/brcm80211/brcmfmac/usb.c +++ b/drivers/net/wireless/brcm80211/brcmfmac/usb.c @@ -669,12 +669,18 @@ static int brcmf_usb_up(struct device *dev) static void brcmf_cancel_all_urbs(struct brcmf_usbdev_info *devinfo) { + int i; + if (devinfo->ctl_urb) usb_kill_urb(devinfo->ctl_urb); if (devinfo->bulk_urb) usb_kill_urb(devinfo->bulk_urb); - brcmf_usb_free_q(&devinfo->tx_postq, true); - brcmf_usb_free_q(&devinfo->rx_postq, true); + if (devinfo->tx_reqs) + for (i = 0; i < devinfo->bus_pub.ntxq; i++) + usb_kill_urb(devinfo->tx_reqs[i].urb); + if (devinfo->rx_reqs) + for (i = 0; i < devinfo->bus_pub.nrxq; i++) + usb_kill_urb(devinfo->rx_reqs[i].urb); } static void brcmf_usb_down(struct device *dev) -- 2.20.1