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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?TgcHaeai42QUU0lFoK00gyY5aSsFfbwox/JarisQxpaFMWiVfYmG55Tr3YGR?= =?us-ascii?Q?3Eaieg9/S6KTv6uddKnZcE4p1upJzk549zX/gkceM/W8YfCTodlBJH5YKpev?= =?us-ascii?Q?l3DH+Dnd8/GsnkaonVXAajjCbIcUPWkMO6A7yDXbnwnVuW0kzLsG3a0r/luZ?= =?us-ascii?Q?SprQuXnBSEFXT+76HAS70ru2faHdWKu5RI/atr4N/7WpJ4A3Ku4DS2WyS4uI?= =?us-ascii?Q?4T5QBFk25oj+KNsz0ulynEU7gWA7qTrhWRtdS6CdgJAKqump70vu/oxFUSgs?= =?us-ascii?Q?GrRwN+juFVii1yhZZ7GW6W6jiAnqYEv0e8eIcUi10BPHtfUNlUviyD+HooVH?= =?us-ascii?Q?noiGFvmMR2mSp1CldMz3taq+kRKwyNiBISWZsNlSiigbaYzI9xWPk2THw0ai?= =?us-ascii?Q?w9zOF3c1phJTcaKwIAg7nsG/xAJug7c/9VcsDK+vZCeJgK1ADNHitoUMyNL4?= =?us-ascii?Q?JPzvd3qc8+1u3vTsqo752Xncn6ivrEQtkrGm35pqPtXkqlm1Zrjd5Vih8WfS?= =?us-ascii?Q?6zFtAA7bjg2NmdvfICT17QgG4BJgcZaVoUxK/BeB9UaRKkSOPjTCwREzfCjj?= =?us-ascii?Q?piBiKNbDgAaEbstjbJSJ4R4ufQkMUWPdy7C1qWpgk1Wm5Wcbkkdeuyyfcoy9?= =?us-ascii?Q?mt3oZEG4oZzt1fA8BkXs67gn+qVS5A7R83+1jRGovDFBgKQD5yozuCbJKhT8?= =?us-ascii?Q?hqnBYFL7fbvggQglmiUjhiKPxkAAeFxkHWNjMjpuq1v/3gbewoyl4+382n5S?= =?us-ascii?Q?aW+3iv0iMdM9EQrdIJkEMmQHyPZbNoVzAoW6txbars2UZBnHc8UA6iOaCXjO?= =?us-ascii?Q?2LdwGV8ShT/BJ3nJzXuFBkHslrwnth89R2LL0OD8sBDRjT+AnYpXiyuUCOZr?= =?us-ascii?Q?LhJPMOlAEMXPVbipzxUGfYGL3S8SqZY4P09jF6Q4q5F4wQcpM5TS+NrtSLO1?= =?us-ascii?Q?ae2KqMr0uX9z2i/qWysLpHXnJMhYCvBO0XxsuM2dT8HwqFCT9daMCddQwE8b?= =?us-ascii?Q?Gh9GfsjN9Yo88oztgHqy7+LdJosx6tn59hMfSq4wLPP8bt1v1tOYSPs86obr?= =?us-ascii?Q?m/9P9W89K1draFFsUfLcgfmit/e8OM9mdB4HN7/CCRHnPUjuH8UHVxCj3fHd?= =?us-ascii?Q?5SjZRsE9sjMv5gm4tERbLJE5oiNMyz9OuK6US6jeQCMh/hRdIBUtYJR7WDe6?= =?us-ascii?Q?83DSBjTrX771KzpaqOa5ZrfEMIghzkv4vmOrUs/TjJgsiM7jij0Fdq4rUzRU?= =?us-ascii?Q?ZLQ+PDpFGFjTBF5/xFQhs90o528oBs9T7g3mo5jfbOAplWXLVU2M2IzDIVcn?= =?us-ascii?Q?rZ8aOjcWxrQydbR+yMTt6inc5N+YcT7DaQIpStuzU0Hb5ocThdwP7eHEfqym?= =?us-ascii?Q?3YB1qECoEDXj/r70X0SPRVJRGQm/8RWG1o/Yo4yXbUVPo4AHIxP4Pbp18ork?= =?us-ascii?Q?CcKJIx1i+vOIEsQQu9WOHYPWJnHhqlIu0pr9dSTFLxWK1n5quUgi8giqi6zW?= =?us-ascii?Q?V2SJh4gISmMIYqKGwA+Wbir+YhFRSuZD8u/vQt+r53hFDWb+o7An7u+7Yzjz?= =?us-ascii?Q?/aSVFXOA/sRFahJoLdU=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1c6af546-08d7-4b01-315b-08dd569a5445 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Feb 2025 19:18:19.6873 (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: rVKoGzLp7kDa5FJLOmS6t/Oxh/ZcuftRupciK4itiSkKP8zfsvPxqIXxBi8FS3gM X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB9519 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250226_111823_675682_025B4A9C X-CRM114-Status: GOOD ( 11.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Feb 26, 2025 at 10:57:00AM -0800, Nicolin Chen wrote: > OK, I see. But we are also changing the behavior for the > !CONFIG_IOMMU_DMA configuration, in which case all other iommu > functions seem to return -ENODEV. And I assume we would need a > justification for such a change? > > Perhaps, this can be explicit, just to keep the consistency: > /* NOP if IOMMU driver reports SW_MSI reserved regions */ > return IS_ENABLED(CONFIG_IOMMU_DMA) ? 0 : -ENODEV; Hurm, I donno, if we don't have a IRQ driver that supports it then it doesn't matter that IOMMU_DMA is off either because there is nothing that would call into IOMMU_DMA in the first place. Success still seems like the right answer on such a weirdo kconfig. Jason