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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 5EA28C43142 for ; Tue, 26 Jun 2018 09:02:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C3B426752 for ; Tue, 26 Jun 2018 09:02:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C3B426752 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net 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 S933778AbeFZJCM (ORCPT ); Tue, 26 Jun 2018 05:02:12 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:59038 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932125AbeFZJCK (ORCPT ); Tue, 26 Jun 2018 05:02:10 -0400 Received: from localhost (unknown [221.164.75.83]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 3E86F12573ED4; Tue, 26 Jun 2018 02:02:09 -0700 (PDT) Date: Tue, 26 Jun 2018 18:01:34 +0900 (KST) Message-Id: <20180626.180134.216760218494444800.davem@davemloft.net> To: jslaby@suse.cz Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH 1/1] r8152: napi hangup fix after disconnect From: David Miller In-Reply-To: <20180625072627.9109-1-jslaby@suse.cz> References: <20180625072627.9109-1-jslaby@suse.cz> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 26 Jun 2018 02:02:10 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jiri Slaby Date: Mon, 25 Jun 2018 09:26:27 +0200 > 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 Applied, thank you.