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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?wY5NrCssh7UsFtjT4HKjdx3ofwbrFfB/B6YEz6DW7jqmyOIutQosjfHHeuc4?= =?us-ascii?Q?FO2vsWMpghgQvFsz+M5heJmk6LX3fi41HilRZLlOCbt5fPS035eG0qOW1gi4?= =?us-ascii?Q?V8jeSbycaXpEGN7u0YjiEvzHQfoW1CW8P4ClpjNINF3kFTRCA8nuEyOPVYGi?= =?us-ascii?Q?3KNjs6Sa+7sZwiR8bQeMZrIuYuP/76vJa2bZ7H32hGhh7ycAQuWa7Nz5goHK?= =?us-ascii?Q?NG5wDCOlnq77MoscOampoL2UtLWRmFrH6JmtrX9ij/tMF66HAoK4zcr5Mq8/?= =?us-ascii?Q?Kd9OXuk6RY/c4UpnVHbLHy12epg0MUU3Ufq79G8yPgAR8IWnUBr7Fn69aeuB?= =?us-ascii?Q?qwiTNUb1fx6/zxc7PRAkyJnGZLXCrPu0C7A6/THpdgghCobCZqTYafygvThy?= =?us-ascii?Q?OF0Fhaxn1epFTbmnkCvB7ZcIjEpDAO3+ut/4I9/MZjapRdELV6MycgIGZwlz?= =?us-ascii?Q?mHTus36y67VOewa9bvAQIK3JuprD3/8f1ER20xvjOlYGt888hRtG2WFZqRMO?= =?us-ascii?Q?uqCokWRlRMJ7XIvKngmEL6IOOPA0Dk6ozEbGv7RK7jSKnwHS4UqcJZpahShZ?= =?us-ascii?Q?+PdUwXfGAxWwxOsqLQhdInNU7IM0rhdXnOex70J8aKai+WfhS/JQXrh7wcHX?= =?us-ascii?Q?xURplpQsiJrWJvcg0RFnDZlLLwp2ieMfbUngtgYEW904wejPAKuuGWUfQvXb?= =?us-ascii?Q?OV3BdO/oQxqUUMSwhpTh4da25yjxo9wgxB7Xhbb2Kip7+SZq52zno3j9oeEs?= =?us-ascii?Q?NLWW9qLxU0RhuBIcRZWP5GuTHYi1kQoCk0GxaK1FT6+KmeLbG6/pi55IVl+E?= =?us-ascii?Q?zRcUURKRYuCXujrc+csMwBGZQ7DiSnfNgopacOpU1CWR+6f7WX1Llz9yRxNr?= =?us-ascii?Q?WcR+rIaQqas+OodKfwMm0Ey+s7agFen+HJT/zHAmuPKaj/IqNlHONZFN3cBV?= =?us-ascii?Q?L/t7ZV/dbtkuiii2L9mHMeXNM1vnm1HfEFet6hqDX3fEgXkVrkr3TWQlBgtH?= =?us-ascii?Q?HxqGZqKdYneIQyKoy7zndCngcodYOEk7OSCNBTxuxa9PKbzdarzXBQNRB4dL?= =?us-ascii?Q?cet2YRBP2E0u60UH9OfDDvKROkTtePgR3y18cFPwoWrYEPE/dPhzXwShahII?= =?us-ascii?Q?2nI+PWKYje2Oku4MHdqQ+Mi08aYHpiy8gJuaB9ORqS7SzU2IME782LXW9zVO?= =?us-ascii?Q?opnD5fCHLzmLnFeK/dIgTz+7gaKhXvAZy1LfyTyr9nIB7gIp7tGEWiIw7Koj?= =?us-ascii?Q?0RcejXpyEk7JPp6ZImSGUfy90N5BOft/dfLwkK+22TzlaNx3hG5n00iAPwIF?= =?us-ascii?Q?6wKsl++kgl+m0V+6F50mVGS3ZnHqm2bfxzu2TyQ2nL6KuLd2oiMCKFMFGq5a?= =?us-ascii?Q?7gZgRoR/1QvTZ2bvFIZ/4YL9P3F7bHk4D9aa1CsdM9g1htcw5CDcQrsDRxmB?= =?us-ascii?Q?D2453DXtxmDaKWdMYiC9II2V1OqUz4JTgPU5jgsbwsbbfFt7lbm7LcjIOSeh?= =?us-ascii?Q?Fg9OFkn0YpsW03GtuGIpHm6PgYoPaOWXRy1RArrrYM116wGSzyeAwqVYsqEL?= =?us-ascii?Q?7A0MzDiduWdQVB6tNhA=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b1a356d3-eee0-44f6-6c6a-08d9efbfed0b X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Feb 2022 13:43:04.6890 (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: aN65iW6lHtXqPiaq+FFoSEU9Bxq/jLZTAbMtvxluDOC6cJsdRfFsfM9KlzsTymgK X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4199 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Mon, Feb 14, 2022 at 02:37:15PM +0100, Greg Kroah-Hartman wrote: > On Mon, Feb 14, 2022 at 09:18:53AM -0400, Jason Gunthorpe wrote: > > On Mon, Feb 14, 2022 at 10:59:50AM +0100, Greg Kroah-Hartman wrote: > > > > > > + if (ret && !drv->no_kernel_api_dma) > > > > + iommu_device_unuse_dma_api(dev); > > > > > > So you are now going to call this for every platform driver _unless_ > > > they set this flag? > > > > Yes, it is necessary because VFIO supports platform devices as well > > and needs to ensure security. Conflicting kernel driver attachements > > must be blocked, just like for PCI. > > A platform device shouldn't be using VFIO, but ugh, oh well, that ship > has sailed :( I don't know why you say that, but yes, this is was set long ago. > And stop it with the "security" mess, do not give people a false sense > of it here please. I'm confused by what you mean. This is all about what we tend to refer to as DMA security - meaning a device's DMA can be controled by a hostile environment and not impact the integrity of the kernel. Jason