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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/zbrU+4alRjT4cVtm8or7xutOZ3MozkLZEfnYP0S4nIsfAk+6uFnbgLkVcVy?= =?us-ascii?Q?NsCMOWYdWzCi4NDpxRnaJB14LNzbv6cs6T6GIYAS80vY26032PEgzw+VMvBI?= =?us-ascii?Q?9lgIQgzBRsV1K8NaJxuqimF26T/CsXjUxSpc3BpEJRrZF7WrGXuL8I7mjOX4?= =?us-ascii?Q?/7H0bF1hzeVfNMOnkFXt1e8U/Vtkk0/K/ObrUJdY64OsKNlVg8BPSjk+K87/?= =?us-ascii?Q?CDQ8LLRyaQGr+iteMjf8DPsvsTqwM6qf5s8UIzuNtImy5/0vx9n7Ztt/2DAT?= =?us-ascii?Q?/UL8LVkdSYjVxZvfEjH98DLV3HMdH36nyyCNuD4S/dGJCiFmYaBaXQidCRNT?= =?us-ascii?Q?8dYeKGiDWbiv/Evov9N9GxWh7d1fVJTIoCnbDuro/OsM0phd/uNOdEbgp/pt?= =?us-ascii?Q?/KTsVwuexE+isZhCgJYY+zqIKdWpDLEOZt/OQsfcGcHxJIjbDMiTAn6bUCD1?= =?us-ascii?Q?U+UiIbojeC+iNmMRXkkcRoVysbNeMw9MLQRB0CT/kWuvHR1Lt5Z3B8wBrDF8?= =?us-ascii?Q?NSPl11dEGiYoOYCXqAAz0Z0HXGeKh5VoAGrKNyB5blkoHT4MqG6hXetzYmIL?= =?us-ascii?Q?SNLdIuH9Xv94X7hUS+liJJkNAz+Hx2ex5u0+eHyAYq/UPkiUqhsyoFwcd2Fe?= =?us-ascii?Q?kuW+w4neF3L0cOGY6cSPqgl4Bfnmrxz37scslhkayCBbF0nAtYtrwC0rroTZ?= =?us-ascii?Q?J/U+lU6x26qeu3LMJzLS6JBjXghNMm4rrqOizJz4dv78ECdc7YvNecmJAjn5?= =?us-ascii?Q?z92tQmnr1DdzCru4D1p4aBZIhV6jRtwm5Iq+xYOVmrFJw5fnFS8VD63crYUa?= =?us-ascii?Q?8mIT8M4NgIuF7lcWIwDJHHbk/cs3aq2PJA8I5l4VIWm/LNquaC4ovaG8Dvag?= =?us-ascii?Q?NI/yOWNkvoJNpBWY3Or00uw765N1MldpzZqTOyReHqc3I+oMrknn0R02B0Yu?= =?us-ascii?Q?mzj8/SgdVXVXjOXkgO2eDbgboRXB2dY++4YloK2MPrn1OfIYHCykgiK71H5+?= =?us-ascii?Q?z33mDOl863R282B9hv+/jl/Mej7WgZbYfty5FdwMpeukATnn6hdOKbRXbnXx?= =?us-ascii?Q?cDsv3vv/R0+oaIlQe7d5PIHIuB1KUgAreRwV51jleQe61gRvrQDAbKM6k0c0?= =?us-ascii?Q?OTvIBRHnPALmpQe3axg0LJrI6J7pmZFdsohriHP2e7jUwIHXxReeZ5h64YHQ?= =?us-ascii?Q?y5bU6r0vDal/28hfk0WhGzsZbLYYpYwlAblaXNefO2219ONhhPpxMuCfmfjz?= =?us-ascii?Q?4yzbUz0nJUr3nbU7fLZFYc3jtjD3sgR0FsWmahCfR18rWmhpOBnCdZ8IN3VE?= =?us-ascii?Q?Fw7njc2O+8nGGv5XIGi5mR5vJzO1qsW6PegL4aGQovSOiH6Dc86erFlYbK+a?= =?us-ascii?Q?2yUaj9ZFAaKbGye0SQ8XCSAIMr0XcbpMAEohP90htM6Zvjkf5uWkcWkPLPl2?= =?us-ascii?Q?0SiVToP6kDNTjSBp4mzvG6PIgsEecYYE9iNxADp99XFVi2CSl85A5pEX61yw?= =?us-ascii?Q?7NnW/ccpoP6eSQCmCgnBD+Ttc2LgQj8+5Anc63yrpeLDKr74qZ84b85xbHI4?= =?us-ascii?Q?R8holnUVUmyO2TvbFNvT80Yq0ORahy0nv+W/mXsSx8bT4m9JNvqrFLtHJlUe?= =?us-ascii?Q?nhGvdZBhhRE8voOMRaArZK175N9Rj8s+RfQUr/bpSl868wI43+I9947iBEOI?= =?us-ascii?Q?KNNEAg=3D=3D?= X-OriginatorOrg: corigine.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6d716d11-dda0-4574-352b-08db207dc646 X-MS-Exchange-CrossTenant-AuthSource: PH0PR13MB4842.namprd13.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Mar 2023 09:07:57.4110 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: fe128f2c-073b-4c20-818e-7246a585940c X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 2nCGkN8wDw0RGZU+tIknqjX5VnT+FgAz2yX/aeDcE06Y9PdqIAmDKUdanPfk4R9AJ9X6LTic7c9MVJulpyQZXFQz1J1eJNJpK/5piVu4HNU= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO3PR13MB5703 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Mar 08, 2023 at 10:45:29PM -0800, Jakub Kicinski wrote: > On Wed, 8 Mar 2023 14:10:59 -0300 Luiz Angelo Daros de Luca wrote: > > > Perhaps I am misreading this, perhaps it was discussed elsewhere (I did > > > look), and perhaps it's not important. But prior to this > > > patch a value of 1536 is used. Whereas with this patch the > > > value, calculated in rtl8365mb_port_change_mtu, is > > > ETH_DATA_LEN + VLAN_ETH_HLEN + ETH_FCS_LEN = 1500 + 18 + 4 = 1522. > > > > That value, as mentioned in the commit message, probably came from > > rtl8366rb driver jumbo frame settings. > > The "rtl8366rb family" has 4 levels of jumbo frame size: > > > > #define RTL8366RB_SGCR_MAX_LENGTH_1522 RTL8366RB_SGCR_MAX_LENGTH(0x0) > > #define RTL8366RB_SGCR_MAX_LENGTH_1536 RTL8366RB_SGCR_MAX_LENGTH(0x1) > > #define RTL8366RB_SGCR_MAX_LENGTH_1552 RTL8366RB_SGCR_MAX_LENGTH(0x2) > > #define RTL8366RB_SGCR_MAX_LENGTH_16000 RTL8366RB_SGCR_MAX_LENGTH(0x3) > > > > The first one might be the sum you did. I don't know what 1536 and > > 1552 are for. However, if those cases increase the MTU as well, the > > code will handle it. > > During my tests, changing those similar values or disabling jumbo > > frames wasn't enough to change the switch behavior. As "rtl8365mb > > family" can control frame size byte by byte, I believe it ignores the > > old jumbo registers. > > > > The 1522 size is already in use by other drivers. If there is > > something that requires more room without increasing the MTU, like > > QinQ, we would need to add that extra length to the > > rtl8365mb_port_change_mtu formula and not the initial value. If not, > > the switch will have different frame limits when the user leaves the > > default 1500 MTU or when it changes and reverts the MTU size. > > Could I trouble you for v5 with some form of this explanation in the > commit message? FWIIW, that would address my concern.