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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?cPnHWoQ9ZQrupUEiW83+UorYTwrqjdt7HCe0c1avxCqhj/jgnJiBp+Y/+efU?= =?us-ascii?Q?dc/aNCAr1ZyEGqyAXEdAg48wB8PP7CCRe3rIZsHOohMYBV5CfqQ1jAPLq0zj?= =?us-ascii?Q?0hCG+ihtuVvmMvmR/5wboJZRt9z7r3JXOgl9AM0MM2P+UbfAY4aGWZqSG9Vx?= =?us-ascii?Q?fZfGYbXxsbbW2/JQMlcUpAcY8PzFFin74lGxThhlhKpnw1Jskcs4BM2nSSdP?= =?us-ascii?Q?x/3cGCAkuLgp9xEg3a7AomuUUNI7xys+X0WuPDH5H6nKCfx49k+Q9X9N6phm?= =?us-ascii?Q?qfQrGBiuw23teFBKgOe1o735cI+PHyqKXe45vvorXkp0DCz2jq7hZA1C/fif?= =?us-ascii?Q?dc8/Us6fBy+5PRD7qnWG3GWCo5bBo8AYt8rgwiSInExO8lT7m0bxSGPgtzbD?= =?us-ascii?Q?ELrPz/0NYyoD41TsF3sXNFWfgfszC3YaT2PtPWk5HnLSR7PVUg7wm7HnM7FY?= =?us-ascii?Q?bNE6cFTYO6q+/Oqqz5lypYj8ETajUy5nR4R/mofF//tk4qDsppEDRzFrXxI3?= =?us-ascii?Q?WkTfAcYU6yxGXA0IIjxkMclLdXbtdPBuqY2I5IOLSV2Yk3yFZrJ9A8K65EO5?= =?us-ascii?Q?3SzO2Bu4S0Kt9NKny1Ag/feRGAvxpFkhEgL6ztWiuGbbVt2oFqez2zq/rhUW?= =?us-ascii?Q?GXRaEmz9x93+Cho17VYsNnijHo/Ar9PvU4++utUUEoxGkGMsumOuuAux0DtG?= =?us-ascii?Q?M9iCivH9dcrdQUwGYAwmVYd2LWiSL4B6Qll//o4HaHjPcd3U/JPppihEAvCw?= =?us-ascii?Q?qjBK4g/c0XEjXciCk2GyvMBIwbgwkZgP+UJBGQb5Qt0WgdO5sXBIumF2IwkQ?= =?us-ascii?Q?WYmXR3YHh/JVxh7xLt/n+NeHiGkgMCjFDq6z1CUHgMSlHk/2WqzISad0nwiT?= =?us-ascii?Q?uOmyqkQNKbo4GEM5dOOaFSKFcy+s6mOHAjui2PP5SqLyfDYgXVGfMQbWz1fo?= =?us-ascii?Q?VMiAAfQAgy3TYbo/lgEL1f5YB2z/DW8epoGJmiNstVkFD7Elv4omVUJM7Qj9?= =?us-ascii?Q?78Kj6wiXeYKpH84Wce9TG6h0xSTMrdCpT7bByphxx75uRiAowYf4F3jeY+ha?= =?us-ascii?Q?Bjk0Cwo7GW/qb6LT8dwOPvLwKqTmOz5jnM/No+48b/RbliXMfdq/RmKMHmnN?= =?us-ascii?Q?pi6T0weF6H2qh9M8wMcOi4Y9/Q/DOGMmRZQANtCGw+4x9g+knTyPdssnfuMT?= =?us-ascii?Q?4927uL3IVu/hmTI736ld2VE2vjnkoTp/X4qFl3NMmt/Lkuha1omNo9I3IUZu?= =?us-ascii?Q?Dp5mO5x/ptxz9HMcm+EGPzJ5YBfQtn3Uf8nOoFRleslHv5xxQP7UQghLlP1b?= =?us-ascii?Q?jnb/a3RMDwh024JAJGvd1xdyD73QGgNSMGX5KVp4pOlzSQLW9zY4VykqB4AH?= =?us-ascii?Q?g2+AZSZOea6j5yShAt75QCA9wM2y0tBexuevqixyYtm40npWPf7+qGdwG9wP?= =?us-ascii?Q?S9bNOIdda8I4Crq3/cx6OAYXbWVp1uekWJNMyYYkAtDnGWqPgGOVbAtZDTyM?= =?us-ascii?Q?S+pZkScbbL6ry5EDVVmKpeqzPDMicpfwLY4V9AFQ1c2tDq2OUskGgndYW9+q?= =?us-ascii?Q?Qf22g8fVNQH527Rx01zlY4jPb+wqIYJvmfkoyf9r?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a851e3d8-ad4f-41eb-fd0a-08de01015e1c X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Oct 2025 15:44:12.1811 (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: G3cGS/AfcDTuzm1XeIbFD2/BXvxrsLwz4TiMgjFlCtiM3UfVX7KaG5UyyYoky7oY X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB6896 On Wed, Oct 01, 2025 at 09:03:37AM +0300, Sakari Ailus wrote: > Hi Hans, Jason, > > On Mon, Sep 29, 2025 at 03:30:22PM +0200, Hans Verkuil wrote: > > On 29/09/2025 15:02, Jason Gunthorpe wrote: > > > On Mon, Sep 29, 2025 at 02:18:50PM +0200, Hans Verkuil wrote: > > >> On 29/09/2025 14:07, Jason Gunthorpe wrote: > > >>> On Mon, Sep 29, 2025 at 10:23:47AM +0200, Hans Verkuil wrote: > > >>> > > >>>> Since I am unfamiliar with the iommu core code, I am uncertain whether I am > > >>>> just papering over a bug elsewhere, or whether this is really the correct solution. > > >>> > > >>> It is papering over something, group->domain is not supposed to be > > >>> NULL at this point.. That probably means the iommu driver has not been > > >> > > >> It's group->blocking_domain that's NULL, not group->domain. > > > > > > Er, I thought you were hitting a false positive on this: > > > > > > group->domain != group->blocking_domain > > > > > > ie NULL != NULL > > > > > > But I suppose the whole expression is checking for group->domain > > > already. > > > > > > All your patch does is entirely disable the safetly logic :\ > > > > > > What is isp_attach_iommu() trying to accomplish? It does > > > arm_iommu_detach_device() and then arm_iommu_attach_device() ? > > > > > > Why? > > > > > > Is this trying to force a non-identity translation for ISP? > > The omap3isp driver expects to use its own virtual address space for the > ISP: the video buffers are mapped there as virtually contiguous (physically > they can be whatever). Sure, but where does it do the mapping? I didn't see an iommu_map or any other iommu_* call in this driver. I think it is using dma_map_* to do it - probably dma_map_sg though I could not find it? This is why I gave my remarks, if it is relying on the DMA API for mapping then it should just rely on the DMA API to establish a paging domain and not try to open code something like that. Jason