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=-12.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 5F4B7C64E7A for ; Tue, 1 Dec 2020 07:56:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F234A20656 for ; Tue, 1 Dec 2020 07:56:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="fWIqhmvJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726771AbgLAH4X (ORCPT ); Tue, 1 Dec 2020 02:56:23 -0500 Received: from hqnvemgate25.nvidia.com ([216.228.121.64]:11720 "EHLO hqnvemgate25.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbgLAH4W (ORCPT ); Tue, 1 Dec 2020 02:56:22 -0500 Received: from hqmail.nvidia.com (Not Verified[216.228.121.13]) by hqnvemgate25.nvidia.com (using TLS: TLSv1.2, AES256-SHA) id ; Mon, 30 Nov 2020 23:55:42 -0800 Received: from reg-r-vrt-018-180.nvidia.com (10.124.1.5) by HQMAIL107.nvidia.com (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Tue, 1 Dec 2020 07:55:40 +0000 References: <20201127151205.23492-1-vladbu@nvidia.com> <20201130185222.6b24ed42@kicinski-fedora-pc1c0hjn.DHCP.thefacebook.com> User-agent: mu4e 1.4.12; emacs 26.2.90 From: Vlad Buslov To: Jakub Kicinski CC: , , , , Subject: Re: [PATCH net-next] net: sched: remove redundant 'rtnl_held' argument In-Reply-To: <20201130185222.6b24ed42@kicinski-fedora-pc1c0hjn.DHCP.thefacebook.com> Date: Tue, 1 Dec 2020 09:55:37 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.124.1.5] X-ClientProxiedBy: HQMAIL101.nvidia.com (172.20.187.10) To HQMAIL107.nvidia.com (172.20.187.13) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1; t=1606809342; bh=jKcGEjQYO+hVXe9L5WJkPJWfu2RWLCOoz7w3HH12x3Q=; h=References:User-agent:From:To:CC:Subject:In-Reply-To:Date: Message-ID:MIME-Version:Content-Type:X-Originating-IP: X-ClientProxiedBy; b=fWIqhmvJjzq6VJfRybnLzBUYmq9VJ8EFNBsxw/vZKGRY1EcRZfodUlSetWOm43n8I h0AzCiRrY+DECSYP9StO4MORmFjUjf/FrJaPQxOk3JnfXkEOSfWZCZY4oKbzdCq3B3 f0v3vk9OFIE4J0XMkvvPdXdHOna3swt7WLWey3lM+Qea0LBvjtRf+smZy1n/5xrDxF I3iLgSyYmL9FfCCz5HtGQ82UdgSsufgKHq8jXs5oH6uIErMle3DokHvX8y5TTSYxIa r4jMsPBFwCZu8B9FEQ39BoAz9SuXjZq2724I8NXzk0hAEVgzf4BHs0jmxW2h/bnJ3c SlNa+MKoqBcIA== Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue 01 Dec 2020 at 04:52, Jakub Kicinski wrote: > On Fri, 27 Nov 2020 17:12:05 +0200 Vlad Buslov wrote: >> @@ -2262,7 +2260,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n, >> >> if (prio == 0) { >> tfilter_notify_chain(net, skb, block, q, parent, n, >> - chain, RTM_DELTFILTER, rtnl_held); >> + chain, RTM_DELTFILTER); >> tcf_chain_flush(chain, rtnl_held); >> err = 0; >> goto errout; > > Hum. This looks off. Hi Jakub, Prio==0 means user requests to flush whole chain. In such case rtnl lock is obtained earlier in tc_del_tfilter(): /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc * found), qdisc is not unlocked, classifier type is not specified, * classifier is not unlocked. */ if (!prio || (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || !tcf_proto_is_unlocked(name)) { rtnl_held = true; rtnl_lock(); }