From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B5D1376BCD for ; Wed, 1 Apr 2026 07:21:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775028108; cv=none; b=aVgmnHl9udMByur+6UbNxB7DP5f4fY3JTq8DVtlzb+s2iSnne8q9wX1Gyusp4hgccSoYjTVflbcCiTYPkregQAtu2CZWvVLOfU1PmDJIpHV7vuAE9KmC4cr11o2bAMQGd4F79BBHnLuU9mmE9sCdrGActNCvHB+oxL/8D7f/mco= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775028108; c=relaxed/simple; bh=gxLvRjxkG6rrI0xx5WKcTzsXmfNu+NFI4OdCaaMr5XU=; h=In-Reply-To:References:From:To:Cc:Subject:MIME-Version: Content-Disposition:Content-Type:Message-Id:Date; b=d9RUYVBE6lATM78GS5MsT91+a8lr3QB074PM3CywYSEYwR2C+vCXn8/En4nFcBu2Wmv97xpAZl6YZuCzoNv+Y6pJxtYPdXXdfGwBY7Gfp7M/+MkT6QAgEeOcHmGFBtXpZecFCBcutvrq9EJDBOFls0pL17NuYkUurOUSGB9oZXs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=R41ryk/5; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="R41ryk/5" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=yRM4MS7lMXrkCnlS5Wb2LjAcWP2fmJloN6RcG6v0ddU=; b=R41ryk/50ww9uiCE+0QbzGMg3w pf0RroFFHdyxgyDsoIHxiKoRxaK03owUMqaMcxoAmqmip9RUvA6FvgMy7rIWTL+bL9DKttO/qQvW0 jpkpBw7pqiGLk5qQqnTHiq0kh4YxA9hKSxzl/UO6VV9dD+rMidgvhTDmvQ6pOTbHhKlWZP+FCVgkm W2C6Y6/HdiRoAikzD1VWw5tO/izSj9yLk+xLiCQfHxrZhZXX4rrQaRjZ2GaTbgfNToj55Q2of8c7k TS1O9MkuwGwEASKs1Ywlrzx8+7KMXOe9BXpLtT8V2QwC9uHdDdAUMobVDrpTldk8zoiGDLNq1b11s 3IBCHWGQ==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:35434 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1w7ptR-000000002ge-09rs; Wed, 01 Apr 2026 08:21:37 +0100 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1w7ptO-0000000EatC-39il; Wed, 01 Apr 2026 08:21:34 +0100 In-Reply-To: References: From: "Russell King (Oracle)" To: Andrew Lunn Cc: Alexandre Torgue , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , linux-arm-kernel@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, netdev@vger.kernel.org, Ong Boon Leong , Paolo Abeni Subject: [PATCH net-next v2 05/14] net: stmmac: add TSO check for header length Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="utf-8" Message-Id: Sender: Russell King Date: Wed, 01 Apr 2026 08:21:34 +0100 According to the STM32MP151 documentation which covers dwmac v4.2, the hardware TSO feature can handle header lengths up to a maximum of 1023 bytes. Add a .ndo_features_check() method implementation to check the header length meets these requirements, otherwise fall back to software GSO. Signed-off-by: Russell King (Oracle) --- .../net/ethernet/stmicro/stmmac/stmmac_main.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 2b5bccc727a5..031ffb78f40d 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4385,6 +4385,20 @@ static size_t stmmac_tso_header_size(struct sk_buff *skb) return size; } +/* STM32MP151 (dwmac v4.2) and STM32MP25xx (dwmac v5.3) states for TDES2 normal + * (read format) descriptor that the maximum header length supported for the + * TSO feature is 1023 bytes. + * + * While IPv4 is limited to MAC+VLAN+IPv4+ext+TCP+ext = 138 bytes, the IPv6 + * extension headers aren't similarly limited. + */ +static bool stmmac_tso_valid_packet(struct sk_buff *skb) +{ + size_t header_len = stmmac_tso_header_size(skb); + + return header_len <= 1023; +} + /** * stmmac_tso_xmit - Tx entry point of the driver for oversized frames (TSO) * @skb : the socket buffer @@ -4945,7 +4959,8 @@ static netdev_features_t stmmac_features_check(struct sk_buff *skb, if (skb_is_gso(skb)) { queue = skb_get_queue_mapping(skb); - if (!stmmac_tso_channel_permitted(netdev_priv(dev), queue)) + if (!stmmac_tso_channel_permitted(netdev_priv(dev), queue) || + !stmmac_tso_valid_packet(skb)) features &= ~NETIF_F_GSO_MASK; } -- 2.47.3