From nobody Sun Sep 14 22:31:45 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10EAAC54E76 for ; Tue, 17 Jan 2023 17:35:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233784AbjAQRfe (ORCPT ); Tue, 17 Jan 2023 12:35:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54578 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235755AbjAQRap (ORCPT ); Tue, 17 Jan 2023 12:30:45 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 752C53B0E3; Tue, 17 Jan 2023 09:28:35 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id E3CA3B81974; Tue, 17 Jan 2023 17:28:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96A2AC433EF; Tue, 17 Jan 2023 17:28:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673976512; bh=2LdqyXJpT5P5ecE3clObEutt8QLKp6SjRR2Se4pAym4=; h=From:To:Cc:Subject:Date:From; b=bVn6i/mGFHrv/l+OTMcsK66ZkPjtpUGd55ZD4ZBUs6MkBqwtM/zl1QrLEY5Koj4KV nMXvTJkY7iPFNrf3GG4Gg6nUTM0Xf0cR4up9BDI7HlHs4lU69E5BSw8hMeN0s6FIBf 2MVkbu+xbPlNW6Y+up/Fg82RbNh3sPZckH21iZQtO7URw+IKSSTeaeqo9dl7S9mKXD K3HaxC94lzO/EBMVB7iQ6Z9UBUO/7UHqKtdQUfS+Q9nnMTqqZw3bDZUmjtUqO5ZlML NroP83zqVumB8zadW4CFJJ6aJSWYVWZrAR4KevqFjCHRyj7eanqpmhjUHY9C3XKUYo J5xUTq1d4jK+w== From: Arnd Bergmann To: Saeed Mahameed , Leon Romanovsky Cc: Arnd Bergmann , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Nathan Chancellor , Nick Desaulniers , Tom Rix , Tariq Toukan , Maxim Mikityanskiy , Gal Pressman , Lama Kayal , Moshe Tal , netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev Subject: [PATCH] mlx5: reduce stack usage in mlx5_setup_tc Date: Tue, 17 Jan 2023 18:28:11 +0100 Message-Id: <20230117172825.3170190-1-arnd@kernel.org> X-Mailer: git-send-email 2.39.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Arnd Bergmann Clang warns about excessive stack usage on 32-bit targets: drivers/net/ethernet/mellanox/mlx5/core/en_main.c:3597:12: error: stack fra= me size (1184) exceeds limit (1024) in 'mlx5e_setup_tc' [-Werror,-Wframe-la= rger-than] static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type, It turns out that both the mlx5e_setup_tc_mqprio_dcb() function and the mlx5e_safe_switch_params() function it calls have a copy of 'struct mlx5e_params' on the stack, and this structure is fairly large. Use dynamic allocation for both. Signed-off-by: Arnd Bergmann --- .../net/ethernet/mellanox/mlx5/core/en_main.c | 36 ++++++++++++------- 1 file changed, 23 insertions(+), 13 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/ne= t/ethernet/mellanox/mlx5/core/en_main.c index 6bb0fdaa5efa..e5198c26e383 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -2993,37 +2993,42 @@ static int mlx5e_switch_priv_channels(struct mlx5e_= priv *priv, return err; } =20 -int mlx5e_safe_switch_params(struct mlx5e_priv *priv, +noinline_for_stack int mlx5e_safe_switch_params(struct mlx5e_priv *priv, struct mlx5e_params *params, mlx5e_fp_preactivate preactivate, void *context, bool reset) { - struct mlx5e_channels new_chs =3D {}; + struct mlx5e_channels *new_chs; int err; =20 reset &=3D test_bit(MLX5E_STATE_OPENED, &priv->state); if (!reset) return mlx5e_switch_priv_params(priv, params, preactivate, context); =20 - new_chs.params =3D *params; + new_chs =3D kzalloc(sizeof(*new_chs), GFP_KERNEL); + if (!new_chs) + return -ENOMEM; + new_chs->params =3D *params; =20 - mlx5e_selq_prepare_params(&priv->selq, &new_chs.params); + mlx5e_selq_prepare_params(&priv->selq, &new_chs->params); =20 - err =3D mlx5e_open_channels(priv, &new_chs); + err =3D mlx5e_open_channels(priv, new_chs); if (err) goto err_cancel_selq; =20 - err =3D mlx5e_switch_priv_channels(priv, &new_chs, preactivate, context); + err =3D mlx5e_switch_priv_channels(priv, new_chs, preactivate, context); if (err) goto err_close; =20 + kfree(new_chs); return 0; =20 err_close: - mlx5e_close_channels(&new_chs); + mlx5e_close_channels(new_chs); =20 err_cancel_selq: mlx5e_selq_cancel(&priv->selq); + kfree(new_chs); return err; } =20 @@ -3419,10 +3424,10 @@ static void mlx5e_params_mqprio_reset(struct mlx5e_= params *params) mlx5e_params_mqprio_dcb_set(params, 1); } =20 -static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv *priv, +static noinline_for_stack int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_priv = *priv, struct tc_mqprio_qopt *mqprio) { - struct mlx5e_params new_params; + struct mlx5e_params *new_params; u8 tc =3D mqprio->num_tc; int err; =20 @@ -3431,10 +3436,13 @@ static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_p= riv *priv, if (tc && tc !=3D MLX5E_MAX_NUM_TC) return -EINVAL; =20 - new_params =3D priv->channels.params; - mlx5e_params_mqprio_dcb_set(&new_params, tc ? tc : 1); + new_params =3D kmemdup(&priv->channels.params, + sizeof(priv->channels.params), GFP_KERNEL); + if (!new_params) + return -ENOMEM; + mlx5e_params_mqprio_dcb_set(new_params, tc ? tc : 1); =20 - err =3D mlx5e_safe_switch_params(priv, &new_params, + err =3D mlx5e_safe_switch_params(priv, new_params, mlx5e_num_channels_changed_ctx, NULL, true); =20 if (!err && priv->mqprio_rl) { @@ -3445,6 +3453,8 @@ static int mlx5e_setup_tc_mqprio_dcb(struct mlx5e_pri= v *priv, =20 priv->max_opened_tc =3D max_t(u8, priv->max_opened_tc, mlx5e_get_dcb_num_tc(&priv->channels.params)); + + kfree(new_params); return err; } =20 @@ -3533,7 +3543,7 @@ static struct mlx5e_mqprio_rl *mlx5e_mqprio_rl_create= (struct mlx5_core_dev *mdev return rl; } =20 -static int mlx5e_setup_tc_mqprio_channel(struct mlx5e_priv *priv, +static noinline_for_stack int mlx5e_setup_tc_mqprio_channel(struct mlx5e_p= riv *priv, struct tc_mqprio_qopt_offload *mqprio) { mlx5e_fp_preactivate preactivate; --=20 2.39.0