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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, chao.song@mediatek.com, kuohong.wang@mediatek.com, zhuoliang.zhang@mediatek.com References: <3c0e5c52-4204-ae1e-526a-5f3a5c9738c2@gmail.com> <20210701033920.5167-1-rocco.yue@mediatek.com> From: David Ahern Message-ID: <46a9dbf2-9748-330a-963e-57e615a15440@gmail.com> Date: Wed, 30 Jun 2021 22:41:26 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210701033920.5167-1-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 6/30/21 9:39 PM, Rocco Yue wrote: > On Wed, 2021-06-30 at 21:03 -0600, David Ahern wrote: > On 6/30/21 7:59 PM, Rocco Yue wrote: >>> This patch provides an ipv6 proc file named >>> "disable_gen_linklocal_addr", its absolute path is as follows: >>> "/proc/sys/net/ipv6/conf//disable_gen_linklocal_addr". >>> >>> When the "disable_gen_linklocal_addr" value of a device is 1, >>> it means that this device does not need the Linux kernel to >>> automatically generate the ipv6 link-local address no matter >>> which IN6_ADDR_GEN_MODE is used. >>> >> >> doesn't this duplicate addr_gen_mode == 1 == IN6_ADDR_GEN_MODE_NONE? >> > > Hi David, > > Thanks for your review. > > This patch is different with IN6_ADDR_GEN_MODE_NONE. > > When the addr_gen_mode == IN6_ADDR_GEN_MODE_NONE, the Linux kernel > doesn't automatically generate the ipv6 link-local address. > ... > > After this patch, when the "disable_gen_linklocal_addr" value of a device > is 1, no matter in which addr_gen_mode, the Linux kernel will not automatically > generate an ipv6 link-local for this device. > those 2 sentences are saying the same thing to me. for your use case, why is setting addr_gen_mode == 1 for the device not sufficient?