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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?I36Fz8HYe4eEu7UNFnsfPYEqe3bCGutf294KyI+qTKk9TEbfwYA3S5J32zdX?= =?us-ascii?Q?ZjkJgYcCZ6BiCi7cApyBpesoq39pGDHQdmQLhGfRlHRy/sgCiC1qP16jsAZG?= =?us-ascii?Q?NXPy4mrPRt6ykwqqMfh0MBeZcYpnDG9KZcRMLJj5sFG3iXphA/drvfIXCtoK?= =?us-ascii?Q?rsQix6BpHAuvsdJWZdjNxTJAFNIf/fjGooElnkMISG/JKYfvKCNvO+zlglmz?= =?us-ascii?Q?w66u8Z1taft1Tnm7N5wj2iJCSo6ymjJeO6aW4haihHedROYal+JDHCTP+TMQ?= =?us-ascii?Q?U/lFXiLGJ5/j9O8rFZ7LE+qJHcMdvtv3gC3LHR2Pjqs317kFLJWO9vNhhDWb?= =?us-ascii?Q?/6vv6YZ6bVVu/eYswUpOykfQb62iLiJR1XlYIY0GwZm+EZB6elf2jDrs/c+V?= =?us-ascii?Q?BxQMeIRMp/qB5aCjjiVV4w9qKPZgw4AQC1W76W+YZzOOj4YBZo841A0q95x7?= =?us-ascii?Q?M/pAOKziufx6JEs6lJFBEb8+t+H8RLPVidjnRgePNbY/kwjKZbvtKOFELQnw?= =?us-ascii?Q?Jwfsx2gDvI0KJt/VchvGrJCGybJHY0SaMV0THhmXb6vepk/zu+6CE8cYHT/7?= =?us-ascii?Q?Aj4o80p2dmQXa7Ua5w+9dFtzkALVtHth6rnns0LlLUVXMW5pzhOzIvF7dQWs?= =?us-ascii?Q?qSlJvpPlG+nEwNKWka2RX3VbHugoIFoaHyDQVbbhhYphDRcDalVDiPRR58Un?= =?us-ascii?Q?+E8Piq/BQ5hoNAoNekUncKhKb/Il9sL9NukBwnxk4ltOl370CAlQteycJf7u?= =?us-ascii?Q?XW21x9XJ5zCwYqEXShfNUGE63b+tcTksjcNA4Y7U76qBsRjdWDRSdtqXn+wS?= =?us-ascii?Q?hHTGAXWQkyuHQjDtULU0elEa+HBwRPzJXyXBK69HEa+gwlrIc3LVva5OgVE7?= =?us-ascii?Q?7iDH/Dz/H/uk/sopqdKs1AbdHLSADjE0CAKLU0YZcH+bA9n7p0sJGrVlLoBU?= =?us-ascii?Q?jjUQUv+tgUWCWzjNJe5kNlpET+sXy804QrQ6u8yUonkiH7hTNu4UCZswECf8?= =?us-ascii?Q?xxonm2NuBJPnkt+INXKlJeT+LkjFxKjwvPBz0600hzIAVKJltP/dy8AX3wM5?= =?us-ascii?Q?9Iy/RV4BTWmd/VfkKSLihNy64DEJxpeLqU/gdEjqtblcnjo1sVHeqnXZ6Qr1?= =?us-ascii?Q?Vp1CvbBTWbw3Ry0siytrWwy37/9tQXI9B3IRkmIoPU1fDYLOidokKI/MolqD?= =?us-ascii?Q?a9WQLDNcVjs+HR1Rw4JEzaxZvOhZo7n1Lcr6Dn52BLE4bS4JrK3inrg8cTJX?= =?us-ascii?Q?+yk8wMxmX/NrxQLbRDWNtLc07C2uHKI5WO5evwb8EAN1eYsX/F4IXtB/jiBs?= =?us-ascii?Q?OgQ8lekJWjK6pVo3TP6iVXwfA8W7m3O8mz0KaGduxVWVKUmy3gGNRnNI7pDZ?= =?us-ascii?Q?6touMj2t+rLp6cPPq11qyn2YLEZgI2EH4YV2e/iy2KrBaDvK5H+Md9zoMBO8?= =?us-ascii?Q?sVrMQpJREdwyN7lSp1fIoh8W+i+PRHgYKbxAlCALsElBazYId2QVH7rUlC6k?= =?us-ascii?Q?brRbQ77CaHr4vb7MSpTvA9qiexvGeCoXa6mITkaWkw4uzgQZ8/QWL8Q2bJgc?= =?us-ascii?Q?xliT4bRrKSbpJLlS/ocMixuCiXf+LJTkOB1weL7azy4wpvL4wRPDWIwdSMNu?= =?us-ascii?Q?eqgBzqneyfvKU095JOf7JMVHRmBqGzhZ3B8jAN6ksD3RTkql6+7TB2yl0JBi?= =?us-ascii?Q?o2PNA7I9dTSH6bb3m/rA1YWS408htkRza/7js3IHQoBirpzxh2dN/8JWOqpb?= =?us-ascii?Q?rguReJzxLQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8a55c408-3242-47b3-ecbe-08deb288c0ba X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 May 2026 13:49:16.1132 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Rq5gaDBh41nFF+H9xp9iZ9fma4RzsNdVXs9gvfyEB1z+qYi2eOHBhGRZJ8GLMvTYssQyj0P4NRW50W/f6zFTiw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPF12042BF6F On Thu, May 14, 2026 at 06:00:13PM +0200, Fernando Fernandez Mancera wrote: > Hi Ido, yes this looks good but I am afraid of using time_after(). Sure, a > temporary address should never be older than 2 ~ 7 days. Yet, we allow > configuring it up to 2147483647 (68~ years). And that might cause problems > in 32-bit systems. > > I think we either limit this configuration on sysctl directly or we need to > support this nonsense.. another option would be to move inet6_ifaddr out of > jiffies which is something that I recently added to my TODO list. But that > is a bigger change I do not want to bundle with this one. > > I noticed that ipv6_add_addr() do: > > list_add(&ifa->tmp_list, &idev->tempaddr_list); > > Doesn't it mean the first address that matches the base prefix is indeed the > most recent one? I tried a bit and it seems we can use just the first match > :) It's very unlikely that jiffies is going to be a problem given that these are temporary addresses. A lifetime of months / years defeats the purpose... I'm OK with relying on the list order, but lets add a comment in ipv6_add_addr() just before the address is added to the list. > In addition, I didn't check with Sashiko but it is likely going to complain > about a race condition for a RA arriving right after we have spawned an > address but it has not been added to the tempaddr list. Therefore we would > have two addresses.. anyway, that race is quite unlikely. I also have > planned work on that are to reduce the multiple race windows, currently > there are plenty. I suggest to acknowledge such race condition for now and > improve the code base for the reported scenario. One possible solution is to encode the regeneration state in the regeneration counter of temporary addresses. Currently it's essentially a boolean. We can have: 0 - Pre-regeneration. 1 - Regeneration in progress. 2 - Regeneration done (might have failed). And only reset the state if regeneration was already done. > I propose this small change to your proposed diff, I acknowledge that it is > a bit fragile tho (maybe a comment at ipv6_add_addr() is worth to avoid > breaking this accidentally): Yes, comments where we add to the list and where we derive the newest address based on the order should make this clear.