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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?SYr2k0bOK4vV/nkZZeMxE5KwOXj+mvUS7ArUOAL8sIWlszlO0jSC5KkJrfJB?= =?us-ascii?Q?rFnl5gnyDqE53r9Wk+oSv3fggEmQbxgcen1NOssr0FjfdwtnwxfxMW+b7Ia0?= =?us-ascii?Q?wtu6aqZnXSFdv15ZXXbm73Agu/FKl4ESIEy2Viw+WUf8hUBkVXzWccqk48Ur?= =?us-ascii?Q?IXZEua0oXMaxFA5y2KKDmWt+Jfyfip7iiykF/uQ9LafmH5XwLVhcWewOZVeQ?= =?us-ascii?Q?eOtoH1ILS91uhoBB1bwONReQHHqHU79A3FX5hVOcZBPGWUIgrw4bafkn7az3?= =?us-ascii?Q?0qFKhLQnvJKEzz1h+aKaYqhZV3oMYVL4gCq+v3gXlFunwkUXsaILMTWCz/LA?= =?us-ascii?Q?ayO3uNmyKnI8nacyHcwXEzATzPYwEfcMcpOYZ164SX/CR169SIotewcEOkO4?= =?us-ascii?Q?flUcVXB4dHF/JOWLVDH4L23gJnlf5pXREdW+MQ0b8eEV8cxdUfPsOux8aTDx?= =?us-ascii?Q?1yC99rE9VcisHrjN93U9LyhwiurAdWwIwo5ybACYVsNrLcKQZ04UAxH2uHzV?= =?us-ascii?Q?aw2nX/PhiMLSdTR504vjwne7C2i3b52+VVtokRRhF0V3/Sqs2JbSJc+wTKoJ?= =?us-ascii?Q?8AB2pmIOngO6JkK+3P4yFlGTk+pHxZQmB0IU8gSS+52vg47x1x9+S+R8h6ec?= =?us-ascii?Q?fuji92+hXQdOgnYkasxkYjc0oXZK1brER/eUXTq6n8W5rzbLjbri5VexwgOv?= =?us-ascii?Q?jd1nEnu/BIujVM2LUGKWwuP9ZrN/wfAIwVpU0+TRzt84vQSFzYzvAY9FzPQZ?= =?us-ascii?Q?SJSBjUjWCVcmQszmhmaTtCkF0fVQq+8etugx129okeI5t3CG/Z1ovylXk9dN?= =?us-ascii?Q?YlUqQ+ucVaSoMNMR+KiSrEv6MCtSaN3uJ0lJ+s1ouDjBMz73oqeAwLzEGdvL?= =?us-ascii?Q?JJla9iHiCA249BC1fPzDFD+DBCBPcIaWaIs7Cu8FCoPLkk27ki9kAeCj1Lq9?= =?us-ascii?Q?UItrBMDzgYNCouMzC1oBnbTgBSALwfvZruOwPD/gE2mH6sDXePGKjq3r9Q7T?= =?us-ascii?Q?oTiUPKuYzChdUIfG2r/JMiLKiXLXS3dlj4XrUA/fjjFGFWol1s53CyUWs5lp?= =?us-ascii?Q?v53qiffrCYdi1iuuhIyusyljNHPAq6N/0pCINMpRtw5nmFU+LLGbjKhU6PWl?= =?us-ascii?Q?oXWNIpErQhHQffzF8p/L9wOAwJkhFe/yff+eefE05ZkP3iVL3w+KYObfaB8r?= =?us-ascii?Q?DyR8VwFAl1a3q2iEghMzevpgg2C59AQBlDCvfpNq6Mn2X0KQxJeC0UK1cELJ?= =?us-ascii?Q?/VJ+D2fM3DUSaXmY6HCoVQJLg1EzdHycAL4b2Yp0GMcizcd0QTrv132JfYvM?= =?us-ascii?Q?/SliUPkQQXJl2VrPN5SPPvFk7PiwNTpApQS8h3ouxpjiRB7rkK4F56YqjBAt?= =?us-ascii?Q?T6TRjCOMI8EvbI4qY1ammkCRfiZ6x554y41KGbpPZYwy7zawDbsL0F8546Hy?= =?us-ascii?Q?1WQsZ6gPvCeDcZ/A7L5FbAgamGLUwN0fJQ43THb0J1E4gAQ+ngYQmZtWP3kS?= =?us-ascii?Q?sih9+oAwzEeY6HM6SxzsG8mwmQdFclNUqSRWDpLFiRgEEeYfAvf9LR/zxcOd?= =?us-ascii?Q?cYYm44SySYX4YKFT+TPPbYo5zjSmok9vqzF1IEjR?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2d97268d-de50-4baf-1beb-08db02c9691f X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Jan 2023 13:53:47.9335 (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: gSePNL5u4o/Nj583jKCA4ozYGP0VV2bbkJ4pwe/+T2jnYb8I2/ojUU9xGPcSgF7r X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR12MB6783 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 30, 2023 at 01:49:20PM +0000, Robin Murphy wrote: > All in all, it's only actually the habanalabs ones that I'm slightly wary > of, since they're effectively (mis)using device_iommu_mapped() to infer the > DMA ops implementation, which could potentially go wrong (or at least *more* > wrong) on POWER with this change. I guess the saving grace is that > although IMHO habana is not using the DMA API abstraction properly. If it doesn't work on some archs is their bugs to deal with - we don't need to complexify the core code to tiptoe around around such an abuse in an obscure driver. Jason