Received: by 2002:ac0:a581:0:0:0:0:0 with SMTP id m1-v6csp1843291imm; Sat, 30 Jun 2018 05:35:11 -0700 (PDT) X-Google-Smtp-Source: AAOMgpfYI+svtmVm/MSht0Mg+mPURsqkXyX/wkdXhYaa30Q1yp5Jea1ZItkEgGP/V8ZdLTlnQtCT X-Received: by 2002:a62:484d:: with SMTP id v74-v6mr18355165pfa.256.1530362111090; Sat, 30 Jun 2018 05:35:11 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1530362111; cv=none; d=google.com; s=arc-20160816; b=PrdtovKatfi6v9XYdZoAWT+r9oN3hkWQC4AxcwZVdKg6zlnaN+OAVst3xb9jviIxGn rkRGoiW2NiLJ8TQiQlYGHEp4nIQJC4l3yTfUnBOyp1Yb7JZJsGQ1apEdEjRKMjkbZSnF rxAb4fI4l9LvxpCJOYBbBiCzCxb7Io8/IEXS/l78PKn3zmdwJYG4Au5DSqUXtNOE+l64 mXop8SQ5fyIchc8E0oIolmr2X3zVzrtsWLboJRf/+aJTcPqs4Ei8Kad3AxhHx1lWAbUJ VZlcBm2KmybYR3Ef/8LWhSRU7nPG3KQjuQlJFOb++a5IVVgk1iE54W6XMBuWKdLleZRg GrsA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date :arc-authentication-results; bh=vo0+1KmkqGQ5ueN8lLoLe2+4ctrZ2ExKdimarVVcqZA=; b=Jr1WmmPwn53SKXRtowUgcPIbuXcSOVYNud0iREsTv/RBgu19U6E5/PSz+uT8IEY7s1 980qrYMnjLWASL3y+IhrIKyrhfnXArMWPXkFMOHPX7a5wibYef9lqzryYZlYYvExlz3M /B8PhbKLRmeDNX/cMUEBj8M0lKOtTnuUNBROQWEMQxUBOwp7Q3G13JQwNJ9WzqaijC9g ujMJgjmxVKROngxtRMbpe+BxV7qFeIC524YDZjgCpnsZLB5d4gWTX+mVUMgKqG25BYko V7pLYVhQXd7Tmy/nAQ4e6y/ZsB21iOMKosN6gumxLUDnDxJzxcJWp5Zbg5JW0PtrOa/5 /tsw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id d18-v6si9905980pgp.214.2018.06.30.05.34.55; Sat, 30 Jun 2018 05:35:11 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030444AbeF3M3g (ORCPT + 99 others); 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.