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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KRNVnf3E3nPzfTSpGK668WYEXxn0CgclMmQbo1DRn9xH3+vNm+KzZTLhix49?= =?us-ascii?Q?UR6GqHD9wano7H5J0oEIllbOHA7XDOlderKNwFmKb4pBUCuHTRsCzlWpS7qW?= =?us-ascii?Q?YAlSbquSjlRRB55Q0V5lwi4kTPgaBHmxgICsqM4x86Hv7zf73+5gRPrDpm5S?= =?us-ascii?Q?LU0+qJOlIuwrBNP57Vkltil29gfqRn6GM0NrHto2M69mER9v2KlQCVYodWwj?= =?us-ascii?Q?6XzLOGC3iZG1AwCJ+eS2Or8VRCWmvTD6geNoIkZwfitXfJITIe4/YNpThXCz?= =?us-ascii?Q?fy7OmofMFiacd/mg+lJFmPuTVgeu2Si/lbSLrCBFAkqHoyYY6KfEVZJVT4yW?= =?us-ascii?Q?adIzqF6cU86jAJ/2mbbI13R4WlmZAZ+Td3vjfl+0f2JWcqahG97eZhveIhHq?= =?us-ascii?Q?yjsdbp09u0RZRxB9ZidejeFLjCJJwjepWOvRC5AZz4YN8JgMp/cqrgl6fI/X?= =?us-ascii?Q?IbT/wbjxvCOgppT73fhIfF/H3u3DR025tlSJP+g3oqTqohVUzPuUMATvGegh?= =?us-ascii?Q?lD2awYc50PpuAeJZBmRrjfaAgbO6Mt37Yqk0sRp06IYqPcRAVdgINaV1PPXk?= =?us-ascii?Q?d3fFkD38stsHGwyj5+Z/j3AGZhTX1JmVui3S33ezDlGZ49ZYYsRH+TdBBwuC?= =?us-ascii?Q?133mFy4ZsT9ZqeNZYGgNruv4j9EiH0uZkt/ZbZuwfeRMAw3X15hgkq2HVYYE?= =?us-ascii?Q?A71u8Dxz78LIl39IlZlN/oAD2m2g1JM7zRt3UwrfRBa6ePHaxzkCp5tIv4f5?= =?us-ascii?Q?eyuE4Wr08e2lroyNS6Ygf6pPifcw8yvpySfRszDWXgxavSBRDN2A1a5Ea4jv?= =?us-ascii?Q?EI63Xk2nIu9nOo6r0YLBDYn2eh7G4evv9mlG12/n+CkA0wuNUid/h9jjvDbK?= =?us-ascii?Q?Uopsd54s/EyGIuEGthPQ1w+AvSiwDhv1MM0v4CbtOUWDYXD6Z6sbtmdUwKOP?= =?us-ascii?Q?O7/hL7JarFeJ7nyyxGSQqif5SCBBAyVCRDgZt9RORkl6eN6LoJxrZZbJQIZ4?= =?us-ascii?Q?sVRIqfNupeiwUkQ1e/30mUhkBx2Uf0rsoFPSAZKxStNOpS0hCA+UANAKFUbr?= =?us-ascii?Q?WuuFPwZg1ElvS8dEXIxPkWtSaNRSG/J2yk9ChNleEhS/IibRx41vi2lrlFRo?= =?us-ascii?Q?FbSxzs8R6Oxokd02sF2tzXX0eGAOC6/jUZMuTDa/pkWgygt5HIX5KpH9JI+G?= =?us-ascii?Q?YUL6DKkSVNHHVt+z0i9lRBTL+LblPPEo8I8psAxqCzAyiAMgSCbt27IliWRj?= =?us-ascii?Q?8XT7AWAk/8PiM43CXyF72lKpILBgTrVJxqBoxZhJCL4PD3HfdgMuF99JQNhZ?= =?us-ascii?Q?TQvTJv2O80xTm9Vfd57gF+IB1NgEjfON0dY3uHkPeAORTf4Jy6klZEY93a63?= =?us-ascii?Q?pwXn/5KBYmqhiQaMB+YY6BuN3/18kP0TQv001JzIRS5tR0E1anoxU5797Q/X?= =?us-ascii?Q?UgNb05yXCpbnxLgT6N8BYixqgoTAAMRr2/CDQAS1pApzO5n+MkAGVnpr0hhU?= =?us-ascii?Q?1xMoBdlmkvJ+sng7aEWJvKEx8kYicRHsYHcgS5VjlIKydERNugtndZD9Z4he?= =?us-ascii?Q?nwJOXajAQ6SQB4CAVftyerzV5tcG1yhwRhZIacrjp7XtqN1SVWRLN7n83skI?= =?us-ascii?Q?HeMJrr1938TcgoNDMZN592aO3K1vqXaDcj7HV9qj5oKCiXJBzEvv/eaWJios?= =?us-ascii?Q?MJFVQRTeOvIRQn//PPtSwI/Yu+SAsYtmnHMXe1b5zvcre9Lu?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0146c645-e4a5-4d2c-b912-08df2602da7b X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Oct 2026 12:43:00.8390 (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: /syFiWzKHq/jLDbwCR4wPlPvUanvhDyyCOJXdshZq+ZKB0nyscB4f+HoSk6Unan8 X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA4PR12MB9834 On Mon, Oct 05, 2026 at 08:41:32AM +0200, Karl Mehltretter wrote: > static inline struct page *sg_page(struct scatterlist *sg) > { > #ifdef CONFIG_DEBUG_SG > BUG_ON(sg_is_chain(sg)); > #endif > + sg_dmabuf_cpu_access_check(sg); > return (struct page *)((sg)->page_link & ~SG_PAGE_LINK_MASK); > } I'm not sure I understand the overall intention here, I get what this patch does, but no distro could turn this on by default when it touches *everyone* using scatterlist in a performance sensitive spot, and anyone doing testing can use the existing option - so what is the point? I certainly don't like this patch, and I don't like the word "DMABUF" in the scatterlist at all. If we want to add something it should be a general mechanism under DEBUG_SG that allows anyone to 'hide' the CPU list from any future access. Jason