From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E76B0C3ABC0 for ; Tue, 6 May 2025 13:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xoo6sbESeyMu4C1VAqN+/dYdjb4WLdeB4YQBhu0GSeE=; b=n+0/DnpFk3bATuzxCiOByA421u zIlt7nHdibc4WqwhFw8BCJMu2v2wD/psoKvWUNT8b5ptO5XShaZJdQ4HyKLzTXPYZp4KB31pXazt+ 9EOudSkMWUbrpDiz24IFPGhwpEFswYVGvaPX3iRdv4lyhOpaBeFcCwssvF7bVeVFTon53MYkmcsZ5 YJvaDWIXWqJoJWcWWHid0djkaPGs2UU+QKQx7tNZ+rEJQTQdJjCkZcnWSk2fdQxFtpXPZ6GdwSsT4 d2KecJRozlfEic4t/GnhcHeRVQG5fETQPzMiijfQYKXV1PxukJoPk4MFgmPHl98B6bB6+iA4QINyd iT5pkopg==; 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x86_64-pc-linux-gnu) 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250506_040448_964994_75E09BC7 X-CRM114-Status: GOOD ( 27.62 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --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--