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,URIBL_BLOCKED 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 99300C3279B for ; Sat, 30 Jun 2018 12:29:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5281825871 for ; Sat, 30 Jun 2018 12:29:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5281825871 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 S1030454AbeF3M3g (ORCPT ); Sat, 30 Jun 2018 08:29:36 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:38300 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030246AbeF3M3e (ORCPT ); Sat, 30 Jun 2018 08:29:34 -0400 Received: from localhost (unknown [183.108.164.149]) (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 3A56414240485; Sat, 30 Jun 2018 05:29:32 -0700 (PDT) Date: Sat, 30 Jun 2018 21:29:30 +0900 (KST) Message-Id: <20180630.212930.58049848439397621.davem@davemloft.net> To: haiyangz@microsoft.com, haiyangz@linuxonhyperv.com Cc: netdev@vger.kernel.org, kys@microsoft.com, sthemmin@microsoft.com, olaf@aepfle.de, vkuznets@redhat.com, devel@linuxdriverproject.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] hv_netvsc: split sub-channel setup into async and sync From: David Miller In-Reply-To: <20180629210716.6798-1-haiyangz@linuxonhyperv.com> References: <20180629210716.6798-1-haiyangz@linuxonhyperv.com> 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]); Sat, 30 Jun 2018 05:29:34 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Haiyang Zhang Date: Fri, 29 Jun 2018 14:07:16 -0700 > From: Stephen Hemminger > > When doing device hotplug the sub channel must be async to avoid > deadlock issues because device is discovered in softirq context. > > When doing changes to MTU and number of channels, the setup > must be synchronous to avoid races such as when MTU and device > settings are done in a single ip command. > > Reported-by: Thomas Walker > Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug") > Fixes: 732e49850c5e ("netvsc: fix race on sub channel creation") > Signed-off-by: Stephen Hemminger > Signed-off-by: Haiyang Zhang Applied and queued up for -stable.