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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_GIT autolearn=no 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 EAA43C48BDF for ; Thu, 24 Jun 2021 06:28:15 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 759B160724 for ; Thu, 24 Jun 2021 06:28:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 759B160724 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6La/jP0CiKt0Wld2M2PfcqJgBKP0X+vvzrZzPb1Jkpg=; b=gcE04CwvVsG4hn VTnyAl391NuZwpBsoNIVGXKTJTRFOqth/YrWPXUy3jwJqHV2ZPa4jYSksQ3eP8eIyjN8ZHDhANtc8 9gOGR+40dxaPKFQuScfr8ATNOjCiCqXAorVpp7H2aPdNWZlSMlBLTW3yoFh8YHN3DTd7o+GdNw1TJ +MPiRS1u0EaOMJw6LpViWPvA8mXK261/ouDTGRn71wZ/nUTpT6UEAXhJ5K6LGADwNEfJawLzB2qFy kBj/47X7tPoh0KMbMLwNp/R+yb97/gtsKfuc/DCi7+jedXAQthCWgQ3FYTakGIBWQ/+OQRVpY1dft VQ8THh3c1/YfKEYmC+8w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1lwIqK-00CwU9-RY; Thu, 24 Jun 2021 06:28:04 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1lwIqH-00CwSz-0G; Thu, 24 Jun 2021 06:28:02 +0000 X-UUID: bc36a3e0ed8c4a8e87860d82c89597b2-20210623 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:CC:To:From; bh=+5KQJtVcIC70hhUVRKV5pDZ5YXUoWT9X/ZYYK7FCoyg=; b=ewi2Hlc8OWZJy2w/UqySLMPEjKBakOEMWu3lnOkbWXxtUuIZStDifnAYkL94v+nbp0EVtVFyvP7Wx/dLYQcUi3NOFLKWp47FCASBXjzVWh9f99RtgWE3vugpQQObzvxh0INDhWRBBcCRrNPMB7PueYe57M88+vGGLUR4dBiNdjk=; X-UUID: bc36a3e0ed8c4a8e87860d82c89597b2-20210623 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 168301091; Wed, 23 Jun 2021 23:27:58 -0700 Received: from mtkmbs05n2.mediatek.inc (172.21.101.140) by MTKMBS62N1.mediatek.inc (172.29.193.41) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 23 Jun 2021 23:27:56 -0700 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs05n2.mediatek.inc (172.21.101.140) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 24 Jun 2021 14:27:55 +0800 Received: from localhost.localdomain (10.15.20.246) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 24 Jun 2021 14:27:53 +0800 From: Rocco Yue To: Greg KH , David Ahern CC: "David S . Miller" , Jakub Kicinski , Jonathan Corbet , Hideaki YOSHIFUJI , David Ahern , Matthias Brugger , Felix Fietkau , John Crispin , Sean Wang , Mark Lee , , , , , , , , , , Rocco Yue Subject: Re: [PATCH 1/4] net: if_arp: add ARPHRD_PUREIP type Date: Thu, 24 Jun 2021 14:13:10 +0800 Message-ID: <20210624061310.12315-1-rocco.yue@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: References: MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210623_232801_100515_22556052 X-CRM114-Status: GOOD ( 14.71 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Thu, 2021-06-24 at 07:29 +0200, Greg KH wrote: > > Thanks for the explaination, why is this hardware somehow "special" in > this way that this has never been needed before? > > thanks, > > greg k-h > Before kernel-4.18, RAWIP was the same as PUREIP, neither of them automatically generates an IPv6 link-local address, and the way to generate an IPv6 global address is the same. After kernel-4.18 (include 4.18 version), the behavior of RAWIP had changed due to the following patch: @@ static int ipv6_generate_eui64(u8 *eui, struct net_device *dev) + case ARPHRD_RAWIP: + return addrconf_ifid_rawip(eui, dev); } return -1; } the reason why the kernel doesn't need to generate the link-local address automatically is as follows: In the 3GPP 29.061, here is some description as follows: "in order to avoid any conflict between the link-local address of MS and that of the GGSN, the Interface-Identifier used by the MS to build its link-local address shall be assigned by the GGSN. The GGSN ensures the uniqueness of this Interface-Identifier. Then MT shall then enforce the use of this Interface-Identifier by the TE" In other words, in the cellular network, GGSN determines whether to reply to the Router Solicitation message of UE by identifying the low 64bits of UE interface's ipv6 link-local address. When using a new kernel and RAWIP, kernel will generate an EUI64 format ipv6 link-local address, and if the device uses this address to send RS, GGSN will not reply RA message. Therefore, in that background, we came up with PUREIP to make kernel doesn't generate a ipv6 link-local address in any address generate mode. Thanks, Rocco _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek