From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (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 83FE85221DC; Wed, 30 Sep 2026 21:51:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.84.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790805097; cv=none; b=CvbEPT6yN6r7hEiAmAaMCP1LCk6FkDIjp38CfE1/7qgdYOyXJ8+Wbum/2C+rhsA1M021OUNe5YR9x01HeH3zWsjV0mzo6v4nZzyyA/wv64j0b03wgPz9bNrjO+EI3tMQIbi1RhXB96NyTSJSx64H8HVhUqATblCX2/TVIv3UhZc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790805097; c=relaxed/simple; bh=exmeiMuuq+vo1S+JtVvCfGPRaAN3bi+jqUDLwbtc2NU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NTePOPYCoNovbbkkYkybfaztS09iqhhAiOOl0IxLfcmrYofzLIVS7WS2dwmIWLGeMkJjfpzmbueDFZO8TaJYpB7fyDkZ5PT/XTGJYYzWDJljXGdOdscyr5Dz20SehQt7P9XtqrULi066g+l2TlUcwofkq9Okq9HAnOLgkODmHIo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=WYNB4EVj; arc=none smtp.client-ip=185.246.84.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="WYNB4EVj" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id A16441A1088; Wed, 30 Sep 2026 21:51:30 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 6248160749; Wed, 30 Sep 2026 21:51:30 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 0101A103298BA; Wed, 30 Sep 2026 23:51:23 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1790805089; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=vzOGn7kFlOHjQR1OKolnS+9aTa51YUymd+DOFjdZtfU=; b=WYNB4EVjUV26HzXoImOdERlNMCi/1F9FbbLdz0J/n2iIQHFWJkLmVhws7pZFdkoirpeMeE WHtF1qJ5uvZFz1Kd/bEIUbw2wsw1ccZIe6g9UfGBMwSW6L4T4Caj1jEyHxUWd8Oc02Mrqh NGa//iMhbHpvs0aMbrwvmBMrfjKsO/fDcFmdBI8dhYo54rNcY3NoZbl9Nt3zfFzwONIW7f ESdHMirkK90aVAJo+ssgPAb+VNSYYyNjIbgc3KGTKRwT+4ixZiflaXi0UXzGo2IzgiSMW2 Cms65QhZENJcWqxNEz61EDnq/Wlzlcdv18z9/Th+haP4PFQyB9eb7ZH0FL9XAQ== Message-ID: Date: Wed, 30 Sep 2026 23:51:22 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net v6 5/5] net: stmmac: Disable S-Tag processing on dwmac4 To: Ovidiu Panait , recv.jo@gmail.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@kernel.org, kuba@kernel.org, pabeni@redhat.com, mcoquelin.stm32@gmail.com, alexandre.torgue@foss.st.com, joabreu@synopsys.com, jun.ann.lai@intel.com, yi.fang.gan@intel.com Cc: netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20260928203441.34876-1-ovidiu.panait.rb@renesas.com> <20260928203441.34876-6-ovidiu.panait.rb@renesas.com> Content-Language: en-US From: Maxime Chevallier In-Reply-To: <20260928203441.34876-6-ovidiu.panait.rb@renesas.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 Hi, On 9/28/26 22:34, Ovidiu Panait wrote: > Currently, hardware VLAN stripping is broken for 802.1ad tags. vlan_rx_hw() > hardcodes ETH_P_8021Q when putting the hardware tag into the skb, rather > than using the actual protocol from the packet. Because of this, packets > that contain a 802.1ad outer tag are incorrectly passed up the stack as > having an 802.1Q tag. This causes QinQ ping between two hosts to fail. > > vlan_rx_hw() is shared by dwxgmac2 and dwmac4: on dwxgmac2 the tag type > is available in the RDES3 write-back descriptor (the ET_LT field), so the > outer tag type can be determined based on that info. However, dwmac4 > doesn't seem to provide the tag type. The Length/Type field in RDES3 only > indicates whether the packet is single or double-tagged, not which tag > type was stripped. > > Since dwmac4 cannot report the stripped tag type, it cannot support > hardware S-Tag stripping correctly. Therefore, restrict the > NETIF_F_HW_VLAN_STAG_RX and NETIF_F_HW_VLAN_STAG_FILTER advertisement > to dwxgmac2 only. > > With this, 802.1ad tags are left in place and handled by the software > VLAN path. > > Fixes: 750011e239a5 ("net: stmmac: Add support for HW-accelerated VLAN stripping") > Signed-off-by: Ovidiu Panait > Reviewed-by: Maxime Chevallier I ran your proposed QinQ selftests on stm32mp157a (dwmac4), and it correctly fixes the problem on that core. Tested-by: Maxime Chevallier Maxime > --- > v6 changes: None. > > v5 changes: > - Rebased on top of latest changes. > - Added Reviewed-by tag from Maxime. > > v4 changes: > - Dropped all "double VLAN" references from the commit title/message. > - Rebased on top of the S-VLAN rework. > > drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > index b007ff120471..5af245fd9ba0 100644 > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > @@ -6211,7 +6211,7 @@ static netdev_features_t stmmac_fix_features(struct net_device *dev, > if (priv->plat->bugged_jumbo && (dev->mtu > ETH_DATA_LEN)) > features &= ~NETIF_F_CSUM_MASK; > > - if (dwmac_is_xmac(priv->plat->core_type)) { > + if (priv->plat->core_type == DWMAC_CORE_XGMAC) { > if (features & NETIF_F_HW_VLAN_CTAG_RX) > features |= NETIF_F_HW_VLAN_STAG_RX; > else > @@ -7990,14 +7990,18 @@ static int __stmmac_dvr_probe(struct device *device, > ndev->watchdog_timeo = msecs_to_jiffies(watchdog); > #ifdef STMMAC_VLAN_TAG_USED > /* Both mac100 and gmac support receive VLAN tag detection */ > - ndev->features |= NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_STAG_RX; > + ndev->features |= NETIF_F_HW_VLAN_CTAG_RX; > + if (priv->plat->core_type == DWMAC_CORE_XGMAC) > + ndev->features |= NETIF_F_HW_VLAN_STAG_RX; > + > if (dwmac_is_xmac(priv->plat->core_type)) { > ndev->hw_features |= NETIF_F_HW_VLAN_CTAG_RX; > priv->hw->hw_vlan_en = true; > } > if (priv->dma_cap.vlhash) { > ndev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; > - ndev->features |= NETIF_F_HW_VLAN_STAG_FILTER; > + if (priv->plat->core_type == DWMAC_CORE_XGMAC) > + ndev->features |= NETIF_F_HW_VLAN_STAG_FILTER; > } > if (priv->dma_cap.vlins) > ndev->features |= NETIF_F_HW_VLAN_CTAG_TX;