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Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Matthias Brugger , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com, rocco.yue@gmail.com References: <7087f518-f86e-58fb-6f32-a7cda77fb065@gmail.com> <20210602031502.31600-1-rocco.yue@mediatek.com> From: David Ahern Message-ID: <05efe271-72f8-bc77-8869-ae4685af5ea4@gmail.com> Date: Tue, 1 Jun 2021 22:20:03 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.10.2 MIME-Version: 1.0 In-Reply-To: <20210602031502.31600-1-rocco.yue@mediatek.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 6/1/21 9:15 PM, Rocco Yue wrote: > On Tue, 2021-06-01 at 18:38 -0600, David Ahern wrote: > On 6/1/21 3:16 AM, Rocco Yue wrote: >>> For this patch set, if RA message carries the mtu option, >>> "proc/sys/net/ipv6/conf//ra_mtu" will be updated to the >>> mtu value carried in the last RA message received, and ra_mtu >>> is an independent proc file, which is not affected by the update >>> of interface mtu value. >> >> I am not a fan of more /proc/sys files. >> >> You are adding it to devconf which is good. You can add another link >> attribute, e.g., IFLA_RA_MTU, and have it returned on link queries. >> >> Make sure the attribute can not be sent in a NEWLINK or SETLINK request; >> it should be read-only for GETLINK. > > Thanks for your review and advice. > Do you mean that I should keep the ra_mtu proc and add an another extra netlink msg? > Or only use netlink msg instead of ra_mtu proc? > I will do it. > I meant DEVCONF and notification to userspace was good, but using an IFLA attribute and no proc/sys file is better.