From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.smtp-ext.broadcom.com (lpdvsmtp12.broadcom.com [192.19.144.207]) (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 96D4F4D9F7E; Tue, 22 Sep 2026 22:17:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.19.144.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790115444; cv=none; b=PENhIQGShhcQxDn9N0a4I6nmp9pLf4RWW43AzDhxwOsRBc3FF85gUJSicD+02/MM3r76NC21zJa4B/izqt6O6VmT36v2K4Ew0EOOqBeiyQHMcE3t4tX4Wy2dgqqzOueVD4pcCO7KgdZO5OkAjlnH4yQ+GBWH07/eBUDtZzqAQzI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790115444; c=relaxed/simple; bh=DEd0waVIprXhh5yorRxRzU10ExFfSwXWNXxHuHIukcw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Qk1znXu86wYOohmBLQUuPsUMyYur1/2WnIkLXDDWkyxCB6mvleWCJvJSCfcHOQ7bktVEc4hAia2yTg4Auh6FRYQCZY/UMlpNehRO9Z4AkEq192YxXuF/yiz4Il4AMAV8e5xN7rSCxGV1K63HiA9ANwQH+ET+MXJX0oQJt5WFTVA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=broadcom.com; spf=fail smtp.mailfrom=broadcom.com; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b=eiF+iDAn; arc=none smtp.client-ip=192.19.144.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=broadcom.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=broadcom.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="eiF+iDAn" Received: from mail-acc-it-01.broadcom.com (mail-acc-it-01.acc.broadcom.net [10.35.36.83]) by relay.smtp-ext.broadcom.com (Postfix) with ESMTP id 763D8C0003CC; Tue, 22 Sep 2026 15:17:12 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 relay.smtp-ext.broadcom.com 763D8C0003CC DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=broadcom.com; s=dkimrelay; t=1790115432; bh=DEd0waVIprXhh5yorRxRzU10ExFfSwXWNXxHuHIukcw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eiF+iDAnSiyVA3V28NVeJKQxOG+1QzYqiDU+Tefy/wSOc+eNoGC1l/+epAkUPhKk2 weMIxwiAi+majb/brPxyN17g7/JmL/WDbfB6XUx8p/+iUPlnD9qND/xhk8AolJXDKo NnBIKR6a4GBrbSQhWORnA+Ruis/oGEPRnDa8hnpI= Received: from stbirv-lnx-1.igp.broadcom.net (stbirv-lnx-1.igp.broadcom.net [10.67.48.32]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail-acc-it-01.broadcom.com (Postfix) with ESMTPSA id 659C7AEA3; Tue, 22 Sep 2026 18:17:11 -0400 (EDT) From: Florian Fainelli To: netdev@vger.kernel.org Cc: Florian Fainelli , Doug Berger , Broadcom internal kernel review list , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Zak Kemble , Simon Horman , Ryo Takakura , linux-kernel@vger.kernel.org (open list), Nicolai Buchwitz Subject: [PATCH net 5/6] net: bcmasp: account for offload header in TX short packet padding Date: Tue, 22 Sep 2026 15:16:29 -0700 Message-Id: <20260922221630.3864427-6-florian.fainelli@broadcom.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260922221630.3864427-1-florian.fainelli@broadcom.com> References: <20260922221630.3864427-1-florian.fainelli@broadcom.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit When hardware checksum offload is enabled for an skb, bcmasp_csum_offload() prepends a struct bcmasp_pkt_offload header (20 bytes) to the skb via skb_push(). This increases skb->len and skb_headlen(skb) by sizeof(struct bcmasp_pkt_offload). Because the hardware descriptor processor strips this offload header before transmitting the packet on the wire, the wire packet length is smaller by sizeof(struct bcmasp_pkt_offload). The padding calculation did not account for this extra header, causing short frames to skip padding and be sent on the wire smaller than the minimum Ethernet frame size (ETH_ZLEN + ETH_FCS_LEN). Add sizeof(struct bcmasp_pkt_offload) to the minimum padding threshold when hardware checksum offload is enabled. Fixes: 490cb412007d ("net: bcmasp: Add support for ASP2.0 Ethernet controller") Assisted-by: LLM Signed-off-by: Florian Fainelli --- drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c b/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c index 7a63a592f158..3370cbf1b395 100644 --- a/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c +++ b/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c @@ -236,7 +236,7 @@ static struct sk_buff *bcmasp_csum_offload(struct net_device *dev, static netdev_tx_t bcmasp_xmit(struct sk_buff *skb, struct net_device *dev) { struct bcmasp_intf *intf = netdev_priv(dev); - unsigned int total_bytes, size; + unsigned int total_bytes, size, min_size; int spb_index, nr_frags, i, j; struct bcmasp_tx_cb *txcb; dma_addr_t mapping, valid; @@ -267,8 +267,12 @@ static netdev_tx_t bcmasp_xmit(struct sk_buff *skb, struct net_device *dev) for (i = 0; i <= nr_frags; i++) { if (!i) { size = skb_headlen(skb); - if (!nr_frags && size < (ETH_ZLEN + ETH_FCS_LEN)) { - if (skb_put_padto(skb, ETH_ZLEN + ETH_FCS_LEN)) + min_size = ETH_ZLEN + ETH_FCS_LEN; + if (csum_hw) + min_size += sizeof(struct bcmasp_pkt_offload); + + if (!nr_frags && size < min_size) { + if (skb_put_padto(skb, min_size)) return NETDEV_TX_OK; size = skb->len; } -- 2.34.1