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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C53CC4361A for ; Fri, 4 Dec 2020 21:57:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 308CB22CE3 for ; Fri, 4 Dec 2020 21:57:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729470AbgLDV4u (ORCPT ); Fri, 4 Dec 2020 16:56:50 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:43825 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729268AbgLDV4u (ORCPT ); Fri, 4 Dec 2020 16:56:50 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1607118985; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=I5SlKBv0SkNfskI9GrrnMZNG4079rgC/Hn+iDRemQhI=; b=d6cu0LVJMx6YgVSApQYgvtpXinUvWXmZhBWYr5DB1RWJeFNpEt7wQF0d5k3RSruQOAMOBEr8 LUWE2YxEfW1HRbAMUdzR4IQqlGvndrcj+B94BZq/HYuBQNJuFLuxbh9BmISVoEKneh27EZst E5bt0ls4y156F/hyynuFjxTp560= X-Mailgun-Sending-Ip: 69.72.43.15 X-Mailgun-Sid: WyJiZjI2MiIsICJuZXRkZXZAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-west-2.postgun.com with SMTP id 5fcab08708086a3dc7e9f268 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 04 Dec 2020 21:56:23 GMT Sender: subashab=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 27BEAC43462; Fri, 4 Dec 2020 21:56:23 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: subashab) by smtp.codeaurora.org (Postfix) with ESMTPSA id 6C33CC433CA; Fri, 4 Dec 2020 21:56:22 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 04 Dec 2020 14:56:22 -0700 From: subashab@codeaurora.org To: Loic Poulain Cc: stranche@codeaurora.org, netdev@vger.kernel.org, kuba@kernel.org Subject: Re: [PATCH] net: rmnet: Adjust virtual device MTU on real device capability In-Reply-To: <1607017240-10582-1-git-send-email-loic.poulain@linaro.org> References: <1607017240-10582-1-git-send-email-loic.poulain@linaro.org> Message-ID: <3a2ca2c269911de71df6dca2e981f7fe@codeaurora.org> X-Sender: subashab@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2020-12-03 10:40, Loic Poulain wrote: > A submitted qmap/rmnet packet size can not be larger than the linked > interface (real_dev) MTU. This patch ensures that the rmnet virtual > iface MTU is configured according real device capability. > > Signed-off-by: Loic Poulain > --- > drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > index d58b51d..d1d7328 100644 > --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_vnd.c > @@ -60,9 +60,14 @@ static netdev_tx_t rmnet_vnd_start_xmit(struct > sk_buff > *skb, > > static int rmnet_vnd_change_mtu(struct net_device *rmnet_dev, int > new_mtu) > { > + struct rmnet_priv *priv = netdev_priv(rmnet_dev); > + > if (new_mtu < 0 || new_mtu > RMNET_MAX_PACKET_SIZE) > return -EINVAL; > > + if (priv->real_dev && (new_mtu + RMNET_NEEDED_HEADROOM) > > priv->real_dev->mtu) > + return -EINVAL; > + > rmnet_dev->mtu = new_mtu; > return 0; > } > @@ -242,6 +247,9 @@ int rmnet_vnd_newlink(u8 id, struct net_device > *rmnet_dev, > > priv->real_dev = real_dev; > > + /* Align default MTU with real_dev MTU */ > + rmnet_vnd_change_mtu(rmnet_dev, real_dev->mtu - > RMNET_NEEDED_HEADROOM); > + > rc = register_netdevice(rmnet_dev); > if (!rc) { > ep->egress_dev = rmnet_dev; This would need similar checks in the NETDEV_PRECHANGEMTU netdev notifier.