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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Shc1x6YHab21Z4iQyIKqelzAFfyGrC6HUjGvhDGCjnqxl9+7bU+n09wsNpK2?= =?us-ascii?Q?fEInFY6puASxYhtJSX/v2m8DVLRey1u9Rzmn5nFPG532t7/lXOSe755xjGkC?= =?us-ascii?Q?r/UNfudlbbviFzeTlS3bgCdEkzvJSezc7xaxyK+el+ikKg2/zkB9XI9WKduD?= =?us-ascii?Q?g660KwK0UMzGU7kFv6rs5UjAszYNYaNlmv6UlVCOQyUTbPVoUGyCqaJllVJ2?= =?us-ascii?Q?qNElZEZEwIU6tpoViD2XtbFO2JunSBnLhAz23+84fka/XLyRNRMsYYBIGaq5?= =?us-ascii?Q?qycu+zi8aPWnY4/fSB0wgxR51CEVyZuj0pSqFYmLH/Wbg8XUo0GtWyBQCBMR?= =?us-ascii?Q?0UIUwgGk0X15fcq45qWXh/SPy23dHybZXNf8IkQfT5FGNJxZ+ORgYlslldwW?= =?us-ascii?Q?GQf+oFHIQfqG8kQoRjZTJUBU3fNiGnU8wBcbn62tYF4+lvXPckDm28Wl3F/T?= =?us-ascii?Q?YAo44+/jWpO0X+NVB8AwrUGuQO6tDP4/lnRAZ4wfYnjgzDmzWcf6pt3p3jHo?= =?us-ascii?Q?s5a7NUYfEFMB1YwcRI7elVHIWQDhFb0eifHBr8gx6lrYpVZ8P8vrmeE0WPkH?= =?us-ascii?Q?cnZYnxNvjuxvjGhIypgvf14EpZfsNUnG+vPzfGywKfixZw0S6jN7l0BFusAP?= =?us-ascii?Q?swVaomPXwTM1qGFleOePTQ/SL33TI+U7P/lrb9bZuB007qUTVdn141WQ0Y5V?= =?us-ascii?Q?ymSl6RCWXaDfbeCZO9ETGziAjzCuwfum06vbPNdPB4MJrOrvggxBQuTy7Dy1?= =?us-ascii?Q?sR8joqf9GH6MWit5FnAumg9Q/4K7P4SBm4nPd6+rN8EuMwLczSjILmjiaOoj?= =?us-ascii?Q?GGqsNWmB/hbKJzqrRA71vFpYIIfMW5EKUm0iGsRDyEtR3KBlBBvMfG1iJgBO?= =?us-ascii?Q?JqJygPFGCIouJ4+fqMxrqhCIBjn4k+j3l8V2c85XcGcC4AGGNSETOYphyTA8?= =?us-ascii?Q?ps1MjOuEjv76T7vW94DConZ5lkL1UFfyj4QSSCCQMxG5NWDzhewLTWpZP4MF?= =?us-ascii?Q?3hLSqvTS42oXwUrTiCT+vuJInF96agrMZlF8Mrln7ejazWRIO5MUEkuhEj5I?= =?us-ascii?Q?4FHboDFUMWE7atItzHHmt43fyPe4sFmcjypydtVPZ7M2YA5vRNBxurELiurq?= =?us-ascii?Q?EkK7BeoviKyyqhoa2OgboS+XxcBsCeScTHkvUg6+5mJK/2Wu7uc6sVcxod5v?= =?us-ascii?Q?OeyCBtjRCzcRi29hWswlrwwP6H1/K+GjWwgA/xvuaGYoMAPwJbzCIWhwZXm1?= =?us-ascii?Q?VDR4pu2LdNczIZHZG5Mg+GMhyQoVCCBxV/y2r50P+XWWJ/2o8fVPRMRHmma2?= =?us-ascii?Q?1U08ffnNIV+L5HahVzzcAaK3FOPBkZVeN23l6YnA2HOEnQHrUzhQ/buoFHH7?= =?us-ascii?Q?k8fp+23zxpDRsbCzMxrbje3h2tOxh1orX0xYMRK6oxlE3/OiZvYDhv2061fh?= =?us-ascii?Q?J2qW43RE9qD9zrLZrZt3xnsLgkyAfBtvodnPbo+xkC4i0BNaDMzINC8IVHM8?= =?us-ascii?Q?NoUxosIJZMyvTb9OJnRBGK4rhhlLWt0WugqhZcQ9uhScbTt4etT1Bz4gVhYf?= =?us-ascii?Q?ThAmWgfil89qPVfqT6oekZAUrJ2NrE/YQOk9DSWf?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f1c15cb5-9944-4efb-76e9-08dc16264b75 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Jan 2024 00:01:31.1997 (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: b6ttT+3nMoiPZkdv/TsdWykXLaweuwg7vV0Lw+tcQaOZz6K0WsKsIUZjGoKuwWVH X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9234 On Mon, Jan 15, 2024 at 03:23:33PM -0800, Mina Almasry wrote: > > > You did not answer my question that I asked here, and ignoring this > > > question is preventing us from making any forward progress on this > > > discussion. What do you expect or want skb_frag_page() to do when > > > there is no page in the frag? > > > > I would expect it to do nothing. > > I don't understand. skb_frag_page() with an empty implementation just > results in a compiler error as the function needs to return a page > pointer. Do you actually expect skb_frag_page() to unconditionally > cast frag->netmem to a page pointer? That was explained as > unacceptable over and over again by Jason and Christian as it risks > casting devmem to page; completely unacceptable and will get nacked. > Do you have a suggestion of what skb_frag_page() should do that will > not get nacked by mm? WARN_ON and return NULL seems reasonable? Jason