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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 37C8FC7618A for ; Tue, 14 Mar 2023 17:50:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230250AbjCNRuP (ORCPT ); Tue, 14 Mar 2023 13:50:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229692AbjCNRt7 (ORCPT ); Tue, 14 Mar 2023 13:49:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEA15A7284 for ; Tue, 14 Mar 2023 10:49:57 -0700 (PDT) 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 939C0B81AC7 for ; Tue, 14 Mar 2023 17:49:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53B15C4339C; Tue, 14 Mar 2023 17:49:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678816195; bh=uSHOaJ+YRmaKOcG3VWebM3h4V5yaz47cOLlSn9MAqOo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Iuoyx8EYZG+IJ6RqUh+OTzr8z/hi2/gp3S4nsJb/8iHTnyzsCwPgvpRcVOOszpoDq tKs1DO+rA8kQ5SV8FYumJB49GTg7C3nWipyKFnpmyKZplwyrObqqIA8+YGyGvH5DVA WeL1A/+6e8UKQsKBQkr02iOKwbasgyVB/2emcKPxzsQl0bBpj6fGZNxsHXD03qYsBh kaZMmU56t0Fb8MfIV7tFplHPwilSlfZIe/L0wP56N+McgkD5Q6YjipK7ckXf+2AW54 PJ/bU9V/BFrE/Qyq7OVKVTSkqXmd3mQBgcgYIwfWWtJ0aweP/+aKfhYChBKmGJclfs HRUjDnedftG9A== From: Saeed Mahameed To: "David S. Miller" , Jakub Kicinski , Paolo Abeni , Eric Dumazet Cc: Saeed Mahameed , netdev@vger.kernel.org, Tariq Toukan , Adham Faris Subject: [net 10/14] net/mlx5e: Lower maximum allowed MTU in XSK to match XDP prerequisites Date: Tue, 14 Mar 2023 10:49:36 -0700 Message-Id: <20230314174940.62221-11-saeed@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230314174940.62221-1-saeed@kernel.org> References: <20230314174940.62221-1-saeed@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Adham Faris XSK redirecting XDP programs require linearity, hence applies restrictions on the MTU. For PAGE_SIZE=4K, MTU shouldn't exceed 3498. Features that contradict with XDP such HW-LRO and HW-GRO are enforced by the driver in advance, during XSK params validation, except for MTU, which was not enforced before this patch. This has been spotted during test scenario described below: Attaching xdpsock program (PAGE_SIZE=4K), with MTU < 3498, detaching XDP program, changing the MTU to arbitrary value in the range [3499, 3754], attaching XDP program again, which ended up with failure since MTU is > 3498. This commit lowers the XSK MTU limitation to be aligned with XDP MTU limitation, since XSK socket is meaningless without XDP program. Signed-off-by: Adham Faris Reviewed-by: Tariq Toukan Signed-off-by: Saeed Mahameed --- drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c index 56fc2aebb9ee..a7f2ab22cc40 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c @@ -4169,13 +4169,17 @@ static bool mlx5e_xsk_validate_mtu(struct net_device *netdev, struct xsk_buff_pool *xsk_pool = mlx5e_xsk_get_pool(&chs->params, chs->params.xsk, ix); struct mlx5e_xsk_param xsk; + int max_xdp_mtu; if (!xsk_pool) continue; mlx5e_build_xsk_param(xsk_pool, &xsk); + max_xdp_mtu = mlx5e_xdp_max_mtu(new_params, &xsk); - if (!mlx5e_validate_xsk_param(new_params, &xsk, mdev)) { + /* Validate XSK params and XDP MTU in advance */ + if (!mlx5e_validate_xsk_param(new_params, &xsk, mdev) || + new_params->sw_mtu > max_xdp_mtu) { u32 hr = mlx5e_get_linear_rq_headroom(new_params, &xsk); int max_mtu_frame, max_mtu_page, max_mtu; @@ -4185,9 +4189,9 @@ static bool mlx5e_xsk_validate_mtu(struct net_device *netdev, */ max_mtu_frame = MLX5E_HW2SW_MTU(new_params, xsk.chunk_size - hr); max_mtu_page = MLX5E_HW2SW_MTU(new_params, SKB_MAX_HEAD(0)); - max_mtu = min(max_mtu_frame, max_mtu_page); + max_mtu = min3(max_mtu_frame, max_mtu_page, max_xdp_mtu); - netdev_err(netdev, "MTU %d is too big for an XSK running on channel %u. Try MTU <= %d\n", + netdev_err(netdev, "MTU %d is too big for an XSK running on channel %u or its redirection XDP program. Try MTU <= %d\n", new_params->sw_mtu, ix, max_mtu); return false; } -- 2.39.2