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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 4C890C43381 for ; Thu, 7 Mar 2019 09:34:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1538920835 for ; Thu, 7 Mar 2019 09:34:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726286AbfCGJeg (ORCPT ); Thu, 7 Mar 2019 04:34:36 -0500 Received: from mout.kundenserver.de ([212.227.126.130]:59717 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725747AbfCGJeg (ORCPT ); Thu, 7 Mar 2019 04:34:36 -0500 Received: from wuerfel.lan ([109.192.41.194]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.129]) with ESMTPA (Nemesis) id 1MoNMu-1ghsoJ3rnU-00ooKz; Thu, 07 Mar 2019 10:34:16 +0100 From: Arnd Bergmann To: "David S. Miller" , Florian Fainelli , Jakub Kicinski , Jiri Pirko Cc: Nick Desaulniers , Arnd Bergmann , Kees Cook , Wenwen Wang , Ilya Lesokhin , Pablo Neira Ayuso , Edward Cree , Michal Kubecek , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] ethtool: reduce stack usage with clang Date: Thu, 7 Mar 2019 10:33:35 +0100 Message-Id: <20190307093408.3425010-1-arnd@arndb.de> X-Mailer: git-send-email 2.20.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K1:AQpBvpTMTgac1mdMpFa68Lz1u6kxqu97sFrs8yO6CwxOrNdBXns i/3zDpfANmMIprACgJ+yPHpsW1CGj6Y+P4K8Y/2THNtw0KtDONsteWf0jojs3oOMcvx5i8s nI5JW+5Hbn4Ea7wMX2BVy1DzwRvZeQK5CR5SctNhC2DnWJPRK0AJilmHcTeOYHuouqKUX6/ I8J6H2OUZp5oAC9i976dA== X-UI-Out-Filterresults: notjunk:1;V03:K0:vf7fJ+tdSZs=:U4l4hbGT3tBEvxywEgqRL3 H0lqeQIac/dDlOb4IVkmaz/qQCURstV0nRmbsqBK9EXCImDiNWUXeBwyQuS7X/NgE2W37TjWU GRjyDtOBlnAWEw6ZkscfZLyxFUPd5GooHR+uBUhJWVwgUmsiBJGL6TsFkU4g2uowiCIdG0CgA W6YfVamEhxWM3i8l0qC+/euCQjfuLXbZbRe7oWP2j0ULU7tJzRCj7ISpiR98KSmHhTLGrd1ZJ SHbDnUB2NzaNUlFSY7uIJOrBqXTmQ8ffxWDCpHz1UTXpUvS98YICElgQ9gLBR4sfZFeteNjM4 2oGtX/scpBfOrcosa7k51tnmosVS8WsjimG33Pg36aBR3gy5A8qGAK7Fe5M+QIE6yC/C1F3Bd g/pFbqlihpLppVwxf/gS6AD7NiqtC3KxcHDhrgsv4zsVat1scbCQfM5yR3aXZEr36PDP3Tvah +fX0kvi+fZ/WAXehyAjIlfI2i069JpiiKKxzhmBlHrZ7NDeYHgTRFJnytN9jFEaGk9dPucbAh /iymthgKeYQIm9rovL+hw1UvJCl9fM7biSzqsT1tkFX/jwyWRbjA31pUyafzRw5zVeosTNovq pyMyqjYkppHLqGPhbljHXbszv59Y9Qh5BWppDXboYv8h1DkZQixbIwywTxKOfaDeuML7fnVhW IWCQH6JBc5owJ/EqUsBXNX+v3MtrllcFPgv9Q7QsE5Ln7NINiz3dAo2U9F4QKFJ1b+qgJHYao UYDTKcOxJxBABebWw3gK2WXhcav2zp05pcknVQ== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org clang inlines the dev_ethtool() more aggressively than gcc does, leading to a larger amount of used stack space: net/core/ethtool.c:2536:24: error: stack frame size of 1216 bytes in function 'dev_ethtool' [-Werror,-Wframe-larger-than=] Marking the sub-functions that require the most stack space as noinline_for_stack gives us reasonable behavior on all compilers. Signed-off-by: Arnd Bergmann --- net/core/ethtool.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/net/core/ethtool.c b/net/core/ethtool.c index d4918ffddda8..fcbed78172a0 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -2319,9 +2319,10 @@ static int ethtool_set_tunable(struct net_device *dev, void __user *useraddr) return ret; } -static int ethtool_get_per_queue_coalesce(struct net_device *dev, - void __user *useraddr, - struct ethtool_per_queue_op *per_queue_opt) +static noinline_for_stack int +ethtool_get_per_queue_coalesce(struct net_device *dev, + void __user *useraddr, + struct ethtool_per_queue_op *per_queue_opt) { u32 bit; int ret; @@ -2349,9 +2350,10 @@ static int ethtool_get_per_queue_coalesce(struct net_device *dev, return 0; } -static int ethtool_set_per_queue_coalesce(struct net_device *dev, - void __user *useraddr, - struct ethtool_per_queue_op *per_queue_opt) +static noinline_for_stack int +ethtool_set_per_queue_coalesce(struct net_device *dev, + void __user *useraddr, + struct ethtool_per_queue_op *per_queue_opt) { u32 bit; int i, ret = 0; @@ -2405,7 +2407,7 @@ static int ethtool_set_per_queue_coalesce(struct net_device *dev, return ret; } -static int ethtool_set_per_queue(struct net_device *dev, +static int noinline_for_stack ethtool_set_per_queue(struct net_device *dev, void __user *useraddr, u32 sub_cmd) { struct ethtool_per_queue_op per_queue_opt; @@ -2533,7 +2535,7 @@ static int ethtool_set_fecparam(struct net_device *dev, void __user *useraddr) /* The main entry point in this file. Called from net/core/dev_ioctl.c */ -int dev_ethtool(struct net *net, struct ifreq *ifr) +int noinline_for_stack dev_ethtool(struct net *net, struct ifreq *ifr) { struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name); void __user *useraddr = ifr->ifr_data; -- 2.20.0