From nobody Sun Feb 8 23:03:46 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 F073231062E; Fri, 17 Oct 2025 06:11:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760681493; cv=none; b=EezTcz3p1C+ivryLe7Q0VqmnWtI0wO09nkdbjTzNoFLzm3JF7q65YtVoleO870CnbRegZw5zfxroRjXjLHjrU9iBzUGbC0ckatlniM+7Vq16HjwHFu1bxBte9TpD3bfXoM3zbIJ+6CIaqnm9RDxmoxxIl8yv4ezKdxBJCvv5HXk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760681493; c=relaxed/simple; bh=jUVEbKS16TGx2Muh86hLCxq0Nm8NYW02YAqm3vPLILw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=WTj+0RnXgk1rHrN4Mf22Sx3AJzRN0fDbxvywR2R6ate7XvzVSvzELqXYUUeCTkVTCfniunlr5rNbWoiEKNXttGMOI31NSimjCCJtDOO6CGDxu2oelu2NQA6fgM3E8T250lsainNcE6X/i1ywDyM6jAQ7vM3ogom2GHfGwdQVPrM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Hdq6QNi0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Hdq6QNi0" Received: by smtp.kernel.org (Postfix) with ESMTPS id 8A94CC113D0; Fri, 17 Oct 2025 06:11:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760681492; bh=jUVEbKS16TGx2Muh86hLCxq0Nm8NYW02YAqm3vPLILw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=Hdq6QNi0xde8h8eGHVLeFv9S18G5Mc4wflqLl+kHkPfaA4MY/i5Qhjb8lcWe39+fY cLzn3N44f9H3XpLhdSCrpd0sWzwHGmzb71E4rvF2F6zyNr9Mq6B2uxMXEBjuZ7i14t KSafTrPnmCtCcaNydDh84KM7UCgA1bh98qU/Eok3f73k3Y85C+EFxMuZNX32JVbpSG dwKB8YntQgOrlRjLvhCwlCux7PnyzQRVj9xskMWtoN7sZdPMcsMu4Rmgheod9ev0jj HETreLUPAPc3f8ut1rypKviEXaangQOJ8NB2dF3f3YjXC3Vz3Hilmzgusv4zrh/BiY dcISyS+tbxFeQ== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8232FCCD184; Fri, 17 Oct 2025 06:11:32 +0000 (UTC) From: Rohan G Thomas via B4 Relay Date: Fri, 17 Oct 2025 14:11:19 +0800 Subject: [PATCH net v3 1/3] net: stmmac: vlan: Disable 802.1AD tag insertion offload Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20251017-qbv-fixes-v3-1-d3a42e32646a@altera.com> References: <20251017-qbv-fixes-v3-0-d3a42e32646a@altera.com> In-Reply-To: <20251017-qbv-fixes-v3-0-d3a42e32646a@altera.com> To: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Alexandre Torgue , Jose Abreu , Rohan G Thomas , Boon Khai Ng Cc: netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Rohan G Thomas X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1760681491; l=4281; i=rohan.g.thomas@altera.com; s=20250815; h=from:subject:message-id; bh=0616UyoDlligJPpSZE/pfPD+6seIJyoif/vrOJ0b/GI=; b=EfsGbkXO7Y+nZ9tKoxqEDUGS3y+G6JMMb82kXSkJw56OqgcgzvPRgBxj9WPiwoDnEM3YysNx+ enrELze0XAeAjo0y+v30qGo5cUty7Vu7oldF9z6nwCvsRYmiUMuLdYN X-Developer-Key: i=rohan.g.thomas@altera.com; a=ed25519; pk=5yZXkXswhfUILKAQwoIn7m6uSblwgV5oppxqde4g4TY= X-Endpoint-Received: by B4 Relay for rohan.g.thomas@altera.com/20250815 with auth_id=494 X-Original-From: Rohan G Thomas Reply-To: rohan.g.thomas@altera.com From: Rohan G Thomas The DWMAC IP's VLAN tag insertion offload does not support inserting STAG (802.1AD) and CTAG (802.1Q) types in bytes 13 and 14 using the same MAC_VLAN_Incl and MAC_VLAN_Inner_Incl register configurations. Currently, MAC_VLAN_Incl is configured to offload only STAG type insertion. However, the DWMAC IP inserts a CTAG type when the inner VLAN ID field of the descriptor is not configured, and a STAG type when it is configured. This behavior is not documented and leads to inconsistent double VLAN tagging. Additionally, an unexpected CTAG with VLAN ID 0 is inserted, resulting in frames like: Frame 1: 110 bytes on wire (880 bits), 110 bytes captured (880 bits) Ethernet II, Src: (), Dst: () IEEE 802.1ad, ID: 100 802.1Q Virtual LAN, PRI: 0, DEI: 0, ID: 0 (unexpected) 802.1Q Virtual LAN, PRI: 0, DEI: 0, ID: 200 Internet Protocol Version 4, Src: 192.168.4.10, Dst: 192.168.4.11 Internet Control Message Protocol To avoid this undocumented and incorrect behavior, disable 802.1AD tag insertion offload. Also, don't set CSVL bit. As per the data book, when this bit is set, S-VLAN type (0x88A8) is inserted in the 13th and 14th bytes of transmitted packets and when this bit is reset, C-VLAN type (0x8100) is inserted in the 13th and 14th bytes of transmitted packets. Fixes: 30d932279dc2 ("net: stmmac: Add support for VLAN Insertion Offload") Fixes: e94e3f3b51ce ("net: stmmac: Add support for VLAN Insertion Offload i= n GMAC4+") Fixes: 1d2c7a5fee31 ("net: stmmac: Refactor VLAN implementation") Signed-off-by: Rohan G Thomas Reviewed-by: Boon Khai Ng --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 19 +++++-------------- drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c | 2 +- 2 files changed, 6 insertions(+), 15 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/ne= t/ethernet/stmicro/stmmac/stmmac_main.c index 650d75b73e0b0ecd02d35dd5d6a8742d45188c47..dedaaef3208bfadc105961029f7= 9d0d26c3289d8 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4089,18 +4089,11 @@ static int stmmac_release(struct net_device *dev) static bool stmmac_vlan_insert(struct stmmac_priv *priv, struct sk_buff *s= kb, struct stmmac_tx_queue *tx_q) { - u16 tag =3D 0x0, inner_tag =3D 0x0; - u32 inner_type =3D 0x0; + u16 tag =3D 0x0; struct dma_desc *p; =20 - if (!priv->dma_cap.vlins) + if (!priv->dma_cap.vlins || !skb_vlan_tag_present(skb)) return false; - if (!skb_vlan_tag_present(skb)) - return false; - if (skb->vlan_proto =3D=3D htons(ETH_P_8021AD)) { - inner_tag =3D skb_vlan_tag_get(skb); - inner_type =3D STMMAC_VLAN_INSERT; - } =20 tag =3D skb_vlan_tag_get(skb); =20 @@ -4109,7 +4102,7 @@ static bool stmmac_vlan_insert(struct stmmac_priv *pr= iv, struct sk_buff *skb, else p =3D &tx_q->dma_tx[tx_q->cur_tx]; =20 - if (stmmac_set_desc_vlan_tag(priv, p, tag, inner_tag, inner_type)) + if (stmmac_set_desc_vlan_tag(priv, p, tag, 0x0, 0x0)) return false; =20 stmmac_set_tx_owner(priv, p); @@ -7573,11 +7566,9 @@ int stmmac_dvr_probe(struct device *device, ndev->features |=3D NETIF_F_HW_VLAN_CTAG_FILTER; ndev->features |=3D NETIF_F_HW_VLAN_STAG_FILTER; } - if (priv->dma_cap.vlins) { + if (priv->dma_cap.vlins) ndev->features |=3D NETIF_F_HW_VLAN_CTAG_TX; - if (priv->dma_cap.dvlan) - ndev->features |=3D NETIF_F_HW_VLAN_STAG_TX; - } + #endif priv->msg_enable =3D netif_msg_init(debug, default_msg_level); =20 diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c b/drivers/ne= t/ethernet/stmicro/stmmac/stmmac_vlan.c index 0b6f6228ae35db3d855d8d386c3806a007a9d176..ff02a79c00d4f52a458edde1bcc= 08a0895b2c1c1 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_vlan.c @@ -212,7 +212,7 @@ static void vlan_enable(struct mac_device_info *hw, u32= type) =20 value =3D readl(ioaddr + VLAN_INCL); value |=3D VLAN_VLTI; - value |=3D VLAN_CSVL; /* Only use SVLAN */ + value &=3D ~VLAN_CSVL; /* Only use CVLAN */ value &=3D ~VLAN_VLC; value |=3D (type << VLAN_VLC_SHIFT) & VLAN_VLC; writel(value, ioaddr + VLAN_INCL); --=20 2.43.7