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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A5CADC433EF for ; Wed, 13 Apr 2022 22:03:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235031AbiDMWFk (ORCPT ); Wed, 13 Apr 2022 18:05:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233989AbiDMWFj (ORCPT ); Wed, 13 Apr 2022 18:05:39 -0400 Received: from mail-pf1-x436.google.com (mail-pf1-x436.google.com [IPv6:2607:f8b0:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 030EB222B4; Wed, 13 Apr 2022 15:03:17 -0700 (PDT) Received: by mail-pf1-x436.google.com with SMTP id z16so3178973pfh.3; Wed, 13 Apr 2022 15:03:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=dGjtYEXEvkww7m0I6B/FhETocUOCMDPi+l5G5osJj1U=; b=G0kI8IXgqQDJlkctzDjTvJnEEXc47d7pEzg3lDgcff0PfDjwzkf7StTko4K3YvyBgq xHgbOcxhsCQQV5vYkq2jPJvPpYpxEeMxECtt+pdoCFbdsA0zL1uacTEdwekgJEltnctH MzvQBcUEYln5E8qG70s3p6yT9lcZJFzI7zDVrNw/JzRl/ljrLDijwg1tDc5muAbXm/Ut FsXl+q8mFzoTnARo6spGqMz3KcIRmqOveLIlQTSargRih+x6tTyWXkjK6NnC/wJM+kwt IG4mARNhOG/k9Q8FbrA7I8F4YmRBJfJrDryauKLgosclwmEZCGDeXDHbgXBJ/ZaUyvuC 5rHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=dGjtYEXEvkww7m0I6B/FhETocUOCMDPi+l5G5osJj1U=; b=mbJcDZmUvgeIWX9AiIQEHjt0LVj5+zDIdxWUNU41qA7NZifARcG+rsLvoWxarUca2G N6Jx4N1BceHrFrwDnSW46UOLV/IZGYZcD7ZlKEESKPfMFoExQlLkTCrDIzMF9hgHfM3F 2MpgKADFQO29pIEHzo6UaM6ktjWO5DNZ1XFcaRFWikQ487ZgObNcBD58jhjwa/OcKErz xuo9QGUMhkI39SB0tvDq+DiO+W6026rNGKQTZtYGfNzSZmhaHPErMtmqnCTXZw30S6aj HO9Gvc5rydn52YDE64s3pN3Og+LsXKnSBI0Q5KdY6TtFnI8/I7bmvmEWsExoOvuPtiDi biaA== X-Gm-Message-State: AOAM531sedCvgDgWmG2qByf0704/V7eER3monvUtfVJmvbCJS7oxoHZo DQYPoxLs6KQOxax0420jwh0= X-Google-Smtp-Source: ABdhPJwqmcS7b4vgqqMKmO5kvOHNB11CErkFD7m5F/dvNTL1GQXekl8extuLoXJIc5CI4viacjjdaQ== X-Received: by 2002:a63:bd49:0:b0:39d:a2d3:94a2 with SMTP id d9-20020a63bd49000000b0039da2d394a2mr6977027pgp.242.1649887396477; Wed, 13 Apr 2022 15:03:16 -0700 (PDT) Received: from ?IPV6:2620:15c:2c1:200:4cf8:b337:73c1:2c25? ([2620:15c:2c1:200:4cf8:b337:73c1:2c25]) by smtp.gmail.com with ESMTPSA id y7-20020a056a00180700b00506f420e62asm75922pfa.11.2022.04.13.15.03.14 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 Apr 2022 15:03:15 -0700 (PDT) Message-ID: <2b935c82-ea5c-af47-4455-edf3a629e941@gmail.com> Date: Wed, 13 Apr 2022 15:03:13 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH net-next v3] net/ipv6: Introduce accept_unsolicited_na knob to implement router-side changes for RFC9131 Content-Language: en-US To: David Ahern , Arun Ajith S , netdev@vger.kernel.org Cc: davem@davemloft.net, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, yoshfuji@linux-ipv6.org, kuba@kernel.org, pabeni@redhat.com, corbet@lwn.net, prestwoj@gmail.com, gilligan@arista.com, noureddine@arista.com, gk@arista.com References: <20220413143434.527-1-aajith@arista.com> <5a92f5cd-9af4-4228-dc44-b0c363f30e18@gmail.com> <17769a5b-9569-18ee-d1c0-c8971a42c709@kernel.org> From: Eric Dumazet In-Reply-To: <17769a5b-9569-18ee-d1c0-c8971a42c709@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 4/13/22 15:00, David Ahern wrote: > On 4/13/22 3:22 PM, Eric Dumazet wrote: >> On 4/13/22 07:34, Arun Ajith S wrote: >>> Add a new neighbour cache entry in STALE state for routers on receiving >>> an unsolicited (gratuitous) neighbour advertisement with >>> target link-layer-address option specified. >>> This is similar to the arp_accept configuration for IPv4. >>> A new sysctl endpoint is created to turn on this behaviour: >>> /proc/sys/net/ipv6/conf/interface/accept_unsolicited_na. >> >> Do we really need to expose this to /proc/sys, for every interface added >> in the host ? >> >> /proc files creations/deletion cost a lot in environments >> adding/deleting netns very often. > agree with the general intent (along with the increasing memory costs). > I do think this case should be done as a /proc/sys entry for consistency > with both ARP and existing related NA settings. > >> I would prefer using NETLINK attributes, a single recvmsg() syscall can >> fetch/set hundreds of them. > What do you have in mind here? A link attribute managed through `ip link > set`? Yes, something like that, if this is a netdevice/link attribute.