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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?JAp/cLBxMF3eGCTANBuxo3pwIRjMinlOdttteNo+BHFFFPqFijjyghIWEQX3?= =?us-ascii?Q?OGyufYZ07tTO74JmoLiCMZ9KcIuL4yjZDfPb0bqyBvwqX+KxAhlOcI9OJeqh?= =?us-ascii?Q?JdpaFu5fHvXJlrkp8RtlFFpDQH5b/4wbNMxZBcjhIktisq3mZh8ZjjInq7ip?= =?us-ascii?Q?uN34OPqAs1eOXh6sFiyiuJXtKgS1fWQgqt9/XdYg40q8kuVL0NVXpFQ+PTpP?= =?us-ascii?Q?HN55GIyvfFQWks54S/tZudvQT5+tpqY8pTWXQEA6of2fGZsWIsqRbLHiSycC?= =?us-ascii?Q?/CVk8L0rdi0/H9dQnPehSu51+nCKCU48GIJZOYqXx+0ch5/5Z0iQ0QbqcKBc?= =?us-ascii?Q?pfTd1tGxY3JBNWaeoSvyiVmvmWTz/d4dlWNveFl7AdqIN3QVZxMFz6TfbOdj?= =?us-ascii?Q?i1ThSWJmtMnENi0Du2Wp1qq9Y5GFnxq94mwg51L29O2jLwYQWtFW7Uc2kxDR?= =?us-ascii?Q?3VK75rvX/aNhLxhA3Ll3oWswdlLTkCeGF/a/OBiwUhGK9/XWlooUBwx6k6Pg?= =?us-ascii?Q?bLzpUVpHoIucIn+JVVJ4/a+Qb/rjWwHLnA6kSYi99W59WXe3sAcpeZqWZBhI?= =?us-ascii?Q?5Svn/NjSeA7tFw3pwwtMFcpRTrHCjQULq5cAS2NYqEY4/EC08H+Qrk6WH1Jb?= =?us-ascii?Q?HkwZHLF78lNrxbO8ZKlmggmUnA5GT+dq+SnDWLcEugRyfZjVTswQ4/EE2abN?= =?us-ascii?Q?PJANte8FmFgzibkcv3q/JQJQ3D4NV2CDu0B88dwCh/URreBXBRFbWpTEc5zB?= =?us-ascii?Q?AX3F9nRaTrkW0t4qP1+LUNAp90gZVG21vtVtHSBHnw6PkBiW5Nuy/5NGmpLp?= =?us-ascii?Q?joQTWzLYF9t7W2k0qdDZoJXk0s8U+pF4bIodSZsKl/Xk+UF0rj83oXDMZC4f?= =?us-ascii?Q?LL+7w90NR2dDRa23J64AIOOGv5RBQH4qOxhwZ307Qawub3d/TVW0xXM7fyXd?= =?us-ascii?Q?jxwolhBt0kRuWLirg2Yw7jH1qASgSesX5Zi9LikJgN31lIVPBCKB5dtJcw3K?= =?us-ascii?Q?WgK87jWb5H8mkeWeY1PS6/ZGSne3mfzFhmFN1m8+OOHwcOqa42tiTK5uJzP1?= =?us-ascii?Q?D+skafbLBsjF0ZjudgCnpQeXpxG6bMNfEwK7G8G8MR3r37rrdZz3jocxS7ee?= =?us-ascii?Q?70TDXAydA6nwtOahD0L+5dg5xNPVshN7yw3CmdWVDhJKKys7IcG1xMMLH7be?= =?us-ascii?Q?ylM9e6bJhcz+ChKIDpFPb0Wpvmw0bo3h9qVqO8uiEbnQTUbD7NUm/M4CRK/j?= =?us-ascii?Q?JIvKULXrKFVmLRrbgHFlD2plx8ylbXkfuSmnrnaq0BNr/Hh8Ca8VoEVyX5WN?= =?us-ascii?Q?LuLtXiQ0434+ayMgDySOLGRz2oBC6DQzx0tAWvEZF157E8JQzDHrvX1OpHMx?= =?us-ascii?Q?RVTvpDKk5gDQybiObaXfs1sOg+vPArOy5I90QhmQ8MPHgpjy/tsru1PnIFf2?= =?us-ascii?Q?Q5lEz2/JbP3az3ysVQma3hz6ED646KYo2rmxNEbn1fOtw+G+zHyrjRKb9k6K?= =?us-ascii?Q?FZuro+8oJbIdw0Ow9WMflXZm0+80aXLoI6XExt4/lZfTEcPI/qt9UEYcFeNM?= =?us-ascii?Q?Kq2R+IL95pthnwY/yO4=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 31b0f1f5-ddd0-4ed7-193d-08de115f97a9 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Oct 2025 11:39:00.2985 (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: AwVvZjaUxHfam7TjsvxTg8wT8OApxG23hlxOU7s69X5Z6j8su1yaRymRsM12q/cJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN6PR12MB8491 On Wed, Oct 22, 2025 at 12:08:48AM -0700, Christoph Hellwig wrote: > On Mon, Oct 20, 2025 at 10:08:55AM -0300, Jason Gunthorpe wrote: > > Sure, but this should be handled by the P2P subsystem and PCI quirks, > > IMHO. It isn't VFIOs job.. If people complain about broken HW then it > > is easy to add those things. > > I think it is. You now open up behavior generally that previously > had specific drivers in charge. It has always been available in VFIO. This series is fixing it up to not have the lifetime bugs. > > IDK where Intel GPU lands on this, but VFIO has always supported P2P > > How? It uses follow_pfnmap_start()/etc to fish the MMIO PFNs out of a VMA and stick them into the iommu. Jason