From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx.denx.de (mx.denx.de [89.58.32.78]) (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 9F68B278E49; Tue, 6 May 2025 11:04:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=89.58.32.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746529494; cv=none; b=bzk2rD0sPBVUhzHwwiRVDsYCQagt1PU9EhjQdmF9SqOy6KmvRiVS+o+GLq05fXnyqfFtymQioMczbSJylkvJlFi+R2uP6AYIadk69IXprnP0Z1/kGbuE9z9oGAmwF9a1TJ6vCB6+DqtXqb/QewW2g9j5kV5Bqsk35cMyKMRGwJg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746529494; c=relaxed/simple; bh=pjPSBZN/Mfk5jqUTuqEyMQU0j98SWAtl2iKUPD9duZw=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aGby3zc6+oXRBc84I6v5SFScXIwZYNs3vtZ1ptZ89M0zykPdaek0DmxLQyYnKnpUr02J2KeFEtgB8gjcPdlln1a6IExyJaCUBvlFH0d1cASxOduybZO0Z+xCGhLEtCsgaoJdIXScnsCcQfKU+dLV3VypdWxVXmTfi8JfLU1uMO0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=denx.de; spf=pass smtp.mailfrom=denx.de; dkim=pass (2048-bit key) header.d=denx.de header.i=@denx.de header.b=EAAN14My; arc=none smtp.client-ip=89.58.32.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=denx.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=denx.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=denx.de header.i=@denx.de header.b="EAAN14My" Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id A24331048C2EF; Tue, 6 May 2025 13:04:39 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=mx-20241105; t=1746529483; h=from:subject:date:message-id:to:cc:mime-version:content-type: in-reply-to:references; bh=xoo6sbESeyMu4C1VAqN+/dYdjb4WLdeB4YQBhu0GSeE=; b=EAAN14MyA20btevFZPvu6BMNnnlFaTyQAnW6z0GPRjzZk3Yi2rmN7FPCyS3PA2YvBQj3sl FNhgRG9NVNpLKa+zBxYxtk+GbhVTaeScgVPKvzaRoM8/lYbWfq48kxtIijn92+jzPIPQiw l8Ba8h9SsikRqx7ilXFTkrWNwrxmQkgXJJsTvkqt8iXiBEjUebFgo8lE6dqSf0EmESvUbF cuOoIr0GteTs8hpT8shefM/KbYS8NHPRacoqlZW7Td93crdUK2o4dyjmO/6NJqB3PzqjYJ 3g0flqLo00vwJmk+yY/YB+O00BGgPi1JAIzGH04jBGJF+8NKlC7l/yjPPvkNCA== Date: Tue, 6 May 2025 13:04:38 +0200 From: Lukasz Majewski To: Paolo Abeni Cc: Andrew Lunn , davem@davemloft.net, Eric Dumazet , Jakub Kicinski , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Richard Cochran , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Stefan Wahren , Simon Horman , Andrew Lunn Subject: Re: [net-next v11 4/7] net: mtip: The L2 switch driver for imx287 Message-ID: <20250506130438.149c137e@wsk> In-Reply-To: <61ebe754-d895-47cb-a4b2-bb2650b9ff7b@redhat.com> References: <20250504145538.3881294-1-lukma@denx.de> <20250504145538.3881294-5-lukma@denx.de> <61ebe754-d895-47cb-a4b2-bb2650b9ff7b@redhat.com> Organization: denx.de X-Mailer: Claws Mail 3.19.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/jzWygP56FGIH1XjAZKtG7zv"; protocol="application/pgp-signature"; micalg=pgp-sha512 X-Last-TLS-Session-Version: TLSv1.3 --Sig_/jzWygP56FGIH1XjAZKtG7zv Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Hi Paolo, > On 5/4/25 4:55 PM, Lukasz Majewski wrote: > > + /* This does 16 byte alignment, exactly what we > > need. > > + * The packet length includes FCS, but we don't > > want to > > + * include that when passing upstream as it messes > > up > > + * bridging applications. > > + */ > > + skb =3D netdev_alloc_skb(pndev, pkt_len + > > NET_IP_ALIGN); > > + if (unlikely(!skb)) { > > + dev_dbg(&fep->pdev->dev, > > + "%s: Memory squeeze, dropping > > packet.\n", > > + pndev->name); > > + pndev->stats.rx_dropped++; > > + goto err_mem; > > + } else { > > + skb_reserve(skb, NET_IP_ALIGN); > > + skb_put(skb, pkt_len); /* Make room */ > > + skb_copy_to_linear_data(skb, data, > > pkt_len); > > + skb->protocol =3D eth_type_trans(skb, pndev); > > + napi_gro_receive(&fep->napi, skb); > > + } > > + > > + bdp->cbd_bufaddr =3D dma_map_single(&fep->pdev->dev, > > data, > > + bdp->cbd_datlen, > > + DMA_FROM_DEVICE); > > + if (unlikely(dma_mapping_error(&fep->pdev->dev, > > + bdp->cbd_bufaddr))) > > { > > + dev_err(&fep->pdev->dev, > > + "Failed to map descriptor rx > > buffer\n"); > > + pndev->stats.rx_errors++; > > + pndev->stats.rx_dropped++; > > + dev_kfree_skb_any(skb); > > + goto err_mem; > > + } =20 >=20 > This is doing the mapping and ev. dropping the skb _after_ pushing the > skb up the stack, you must attempt the mapping first. >=20 > > +static void mtip_free_buffers(struct net_device *dev) > > +{ > > + struct mtip_ndev_priv *priv =3D netdev_priv(dev); > > + struct switch_enet_private *fep =3D priv->fep; > > + struct sk_buff *skb; > > + struct cbd_t *bdp; > > + int i; > > + > > + bdp =3D fep->rx_bd_base; > > + for (i =3D 0; i < RX_RING_SIZE; i++) { > > + skb =3D fep->rx_skbuff[i]; > > + > > + if (bdp->cbd_bufaddr) > > + dma_unmap_single(&fep->pdev->dev, > > bdp->cbd_bufaddr, > > + MTIP_SWITCH_RX_FRSIZE, > > + DMA_FROM_DEVICE); > > + if (skb) > > + dev_kfree_skb(skb); =20 >=20 > I suspect that on error paths mtip_free_buffers() can be invoked > multiple consecutive times with any successful allocation in between: > skb will be freed twice. Likely you need to clear fep->rx_skbuff[i] > here. I don't know what I shall say now.... really...=20 >=20 > Side note: this patch is way too big for a proper review: you need to > break it in multiple smaller ones, introducing the basic features > separately. >=20 This code is a basic version of the driver as discussed on March with the community (Andrew). It provides the basic functionality - like separate ports support and then, if required, configures the IP block to perform L2 switching in HW.=20 > Cheers, >=20 > Paolo >=20 Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Erika Unter HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de --Sig_/jzWygP56FGIH1XjAZKtG7zv Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQEzBAEBCgAdFiEEgAyFJ+N6uu6+XupJAR8vZIA0zr0FAmgZ7MYACgkQAR8vZIA0 zr1SGgf/X4lTSbA5wV/GRygSxbZlIT0eA/yxbGzZMIHf7CmhmX20nnuSJN6B51s2 pqBZzQ6lcB8krbIdDTFJ1/W4xeUTeW5SZSI2UCXt6IlimlLwN5NkV3R+QBKEYOuK bjHWjaafO8fSZtmvX67xuiSmBTtKDjLKGY95M0dIp+vahKvru1Fm/mwZL56xHQzR yBrMeVkjFTttMxkIHdbxXTL4LyCefczvGGIiEHMBb/o0UTZzk2bnPeUKVW23/zd+ gUstiifHLosnY9DB/iIhR9kNCwHQGOwpp5VYWKSzG8fdU/ttDgmECQuAqMPncx0T KEKJrQEQUIUNYoZ/4C1nSAM0N6Oh3w== =NnK5 -----END PGP SIGNATURE----- --Sig_/jzWygP56FGIH1XjAZKtG7zv--