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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?tLdAKHqYr9HegDKQdNloxHGBFi+FDGLL2GD9Ts6ZGjC/S4yTfnsSul+6cg2f?= =?us-ascii?Q?ncIyTpdSmAOkd1GEDfng57HpkJkxcuipJ71VNWBY0qSluXLg7e7iP7whVCfj?= =?us-ascii?Q?5CDOjwdj3LRj744tAy8eT0f7d5L3KcZQf/I3YmMsr/tVfsqBezyntgH6unmJ?= =?us-ascii?Q?fyFcIOgA8+5qT9Oi73PQ3XCIFVLv5hJbu41ajWUP+krU91Mz1iOB4Tse2V44?= =?us-ascii?Q?DzQ7XUcrJ8/f21j0fxe9LdmWBXhmZEbSDkH+FmCD1eBvoe2jKrmBXwVoEKfA?= =?us-ascii?Q?9g8BriIGXg+uu776hbD4W3QkoHddQHjudbcl3b8Hvn48NcfK12Yy7n2kfkLn?= =?us-ascii?Q?HIIzs1wg8t6fpeyQW4kfGFzysLIst7t+9vzcuAcGfMXUCrOXodQD6lodf7aM?= =?us-ascii?Q?cy2YcxZBbV/H3i2nU6G3w6fdGoPKN+N5DRKRx8m3mXkvB7FIGtM3St/Rx1Kw?= =?us-ascii?Q?iAsKMVt5zW+t2amV305oKwRBCXASi6qVSgIeKqKcuPbx1aE61XHDdFUQmlYk?= =?us-ascii?Q?MSIl8rv01GlByDYkCFQLWc1U9yakVFb1kcDt9V6sVSdnIXuo5XDIUCUPOMFE?= =?us-ascii?Q?M7utD2fvbaeVk3aM2Rj8DK+YufKdkCdfQUl0kgOTxnh/GM4iQ+4yf9BTiKRy?= =?us-ascii?Q?c69Ym0cpka6Fa9X+9jTrUNAAwg9dko02qSx0jJVdxMzB3BWko+7lg7+S83Lg?= =?us-ascii?Q?BiMcT5q8Har8rYdki5p6UA7tmZtUxT2ZMG8DhfC8z92kAdxx2udGo1QFKze6?= =?us-ascii?Q?zygxuj063k82Qtc0qiG2nCx8M2uDUljtmMetZwDRejCaQeWg87Rk+TEaY1Vp?= =?us-ascii?Q?jFsQ+vVIn6inZ5J/yUOKzSP1qtQkEP8veDQ8MdRGYGmwIILQK26fueHyoqaA?= =?us-ascii?Q?CkWmgzTWxc0qjy6z03vizpFqH3lwqZi/vi6q9ztxoYlQVmNISpKFYTTCll/N?= =?us-ascii?Q?nOngxeEepWgO9PXuyEoxaagG6xMt4zosHLWAhf9wHWX1UIrRrQIPmbM01/HZ?= =?us-ascii?Q?57MaDNA9ZDy4wWEUk5QNCezMD6HcXDUfwTqjvBRI5pZuIYYW2B1Q7P+McUP8?= =?us-ascii?Q?+bEBnOj23Yp1JW3Nj4YQq4U083Hg/3fbcbW2VwRumVKNg+p893EH/3wyEr0J?= =?us-ascii?Q?qryCfXbTwm45GUztR1xUJlASwemYontafKHyh2A2hnc1+Xs8bzfXthnw1y7n?= =?us-ascii?Q?LIjpzGCc3azmR5hF/Rbb10g0zfBJMqwkF05EGsp0UnzflsjBGJ2VHBwo31b9?= =?us-ascii?Q?l1Ctt0Qvo2/AXKjuKldqF1AwuBTOvL9Rj9rPA6+0/TAsRr88biQvsv69uibr?= =?us-ascii?Q?N68lYSnkAxNPnGzTqXtip9iCxdXyrzsPQlNlksdknMzjA1uhs/urutS7lpiz?= =?us-ascii?Q?orVTawtR0Zs9v/NNyyfFRNsvil5h/6ULcXCCsRybtBBE+Fg/lZiUdEsdwM6f?= =?us-ascii?Q?UOwmVikegY3cltuL0Zw1BcFSP0GsX2U1EKLq5hz87cem2M1zedCCKKJOz62V?= =?us-ascii?Q?3g3TyWs7mUI2BEi8az4TgeyngRoQLZP+lN35Uo+EDY2zySx1n6XwZzfisGy1?= =?us-ascii?Q?gzNh9Tf0lqhSnx5gP2gs6Xo2Zqaq494RFjfb1NHa?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9b1be188-cb03-44af-0400-08dd4513486f X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Feb 2025 11:58:48.1498 (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: 8dOX9XdF/2bgLjnUlfkKCujQ7nlCWhPaLveprNTCnTZ6TLI8I9GE8wxgn4tkhGTmakp8LWrXLFpsbT0s0Ux7vA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB7418 On Mon, Feb 03, 2025 at 09:17:08PM +0200, Yong Wang wrote: > > On Wed, 20 Nov 2024 09:08:32 -0800 > Stephen Hemminger wrote: > > > >On Tue, 19 Nov 2024 19:23:53 -0800 > >Jakub Kicinski wrote: > > > >> On Tue, 19 Nov 2024 15:37:03 -0800 Stephen Hemminger wrote: > >> > It looks like loopback and other software devices never get the operstate > >> > set correctly. Not a serious problem, but it is incorrect. > >> > > >> > For example: > >> > $ ip -br link > >> > lo UNKNOWN 00:00:00:00:00:00 > >> > > >> > tap0 UNKNOWN ca:ff:ed:bf:96:a0 > >> > tap1 UNKNOWN 36:f5:16:d1:4c:15 > >> > > >> > For wireless and ethernet devices kernel reports UP and DOWN correctly. > >> > > >> > Looks like some missing bits in dev_open but not sure exactly where. > >> > >> I thought it means the driver doesn't have any notion of the carrier, > >> IOW the carrier will never go down. Basically those drivers don't > >> call netif_carrier_{on,off}() at all, and rely on carrier being on > >> by default at netdev registration. > > > >Tap device does have concept of pseudo carrier. If application has file descriptor > >open it reports carrier, if the device is present but application has not opened > >it then carrier is reported down. > > > > The UNKNOWN operstate sometimes is misleading, for loopback device, the fix seems > simple, we can just set 'dev->operstate = IF_OPER_UP' in its initialization function This comes from the VRF driver which is the only driver I found that does that: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b87ab6b8e517563be372b69bdabd96c672458547 > or add ndo_open handler to call netif_carrier_no, as discussed in thread at > https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=754987#89. I don't see a lot of value in changing this ancient behavior, but I don't think the loopback device should be singled out either. Otherwise, some time from now someone will complain about a different device.