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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 10265ECDFBB for ; Fri, 20 Jul 2018 12:35:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4EB1206B7 for ; Fri, 20 Jul 2018 12:35:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C4EB1206B7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388955AbeGTNXU (ORCPT ); Fri, 20 Jul 2018 09:23:20 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:42882 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387816AbeGTNXT (ORCPT ); Fri, 20 Jul 2018 09:23:19 -0400 Received: from localhost (LFbn-1-12238-233.w90-92.abo.wanadoo.fr [90.92.53.233]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 51EE4C9D; Fri, 20 Jul 2018 12:33:06 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Slaby , linux-usb@vger.kernel.org, netdev@vger.kernel.org, "David S. Miller" Subject: [PATCH 4.14 42/92] r8152: napi hangup fix after disconnect Date: Fri, 20 Jul 2018 14:13:46 +0200 Message-Id: <20180720121420.449376995@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180720121417.206337808@linuxfoundation.org> References: <20180720121417.206337808@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Slaby [ Upstream commit 0ee1f4734967af8321ecebaf9c74221ace34f2d5 ] When unplugging an r8152 adapter while the interface is UP, the NIC becomes unusable. usb->disconnect (aka rtl8152_disconnect) deletes napi. Then, rtl8152_disconnect calls unregister_netdev and that invokes netdev->ndo_stop (aka rtl8152_close). rtl8152_close tries to napi_disable, but the napi is already deleted by disconnect above. So the first while loop in napi_disable never finishes. This results in complete deadlock of the network layer as there is rtnl_mutex held by unregister_netdev. So avoid the call to napi_disable in rtl8152_close when the device is already gone. The other calls to usb_kill_urb, cancel_delayed_work_sync, netif_stop_queue etc. seem to be fine. The urb and netdev is not destroyed yet. Signed-off-by: Jiri Slaby Cc: linux-usb@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/r8152.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -3959,7 +3959,8 @@ static int rtl8152_close(struct net_devi #ifdef CONFIG_PM_SLEEP unregister_pm_notifier(&tp->pm_notifier); #endif - napi_disable(&tp->napi); + if (!test_bit(RTL8152_UNPLUG, &tp->flags)) + napi_disable(&tp->napi); clear_bit(WORK_ENABLE, &tp->flags); usb_kill_urb(tp->intr_urb); cancel_delayed_work_sync(&tp->schedule);