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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?pqSdsoMDq6uqUwSvNmJ4Kr3mfdUVK90ZwwZBgrriQcm7DSfIOA2KoEslLPBK?= =?us-ascii?Q?9Wwm2wkbOqfqeLGZSZGaFpkYNKPYYGAcRVspjvvPpkfb/hcxssDK8uz+kGAU?= =?us-ascii?Q?QjJoOIADNsZQp68cnWrwu2quloVFxbowsPHnyzFA3yD2fpLHV/JmEiTqajDR?= =?us-ascii?Q?Fy8LF3+QDUaeyRfK4rb6/zK64t5uo6KH1JouFZfPMWWCA4qhLse8Xj5+YQW7?= =?us-ascii?Q?EVjOZlxfVqaRcfxuRGV9EZBvVEhJirqImKkrx6HyQ95R/jHZzkw+OGQADE8u?= =?us-ascii?Q?mfYOX/AG+PZKdJ0lfrH4IPcrF/UCqlgHkT7zW77m2NgbqZAuRvIWDq7ltWUi?= =?us-ascii?Q?NN2ushkWd/d4FCl2TN4OV9VAfPltCpUBrGGhM4OFmJ0ml0xcjaBXR+RliK0+?= =?us-ascii?Q?78u+4NCptv+1xolQ2CNLcKTu18ve/Bz7HdJhbPEgZ6H5BT6oaEpru4037EDN?= =?us-ascii?Q?rd9Ai44M0Q8v+hqcdgpQdhKORJPBZ3ftW6BXw7dmITQ7V5SsE4CKU8WClIkP?= =?us-ascii?Q?O9PlLEdEk6agnPLI6Sxcxm6H17v5iT2PQJTVj2cVx+nq9IDXw1s6UMlzVVIw?= =?us-ascii?Q?6KdmfpmniDul/NZQChlPEXTiAjxTZJ0mOmvMInriy6FIJbhn17iushmOnokP?= =?us-ascii?Q?+ByDe6qXXAU6w58veDcxpfety/i0JgN8EcoKm2clWxd+AfLS0DHiQKE8V67h?= =?us-ascii?Q?3+0koOG+aHMtF0xU6Pd8cOoEp9ZweUzrOEXh54ulZvRtQWHhv/TxXb+ad7ld?= =?us-ascii?Q?BuFxDPcoMWxe+54ba8jx5Kf2nZ4gDcjvi91IEMfJDGS8hjeXYG7VgDsIgf/R?= =?us-ascii?Q?pzxWlQZmfzGHuCyIb3kARb6Tq7W0aOjuAqKxJuFVuTudoQKgW7TG2MTZPMVj?= =?us-ascii?Q?PAed1osH6CctklYkB5bV3B1QBSBALXgkQzP7vTDHH1mXREq71amhFr+XSkmm?= =?us-ascii?Q?Z0e36FR9Hct9mBRb6/HGO3e+jglQdjgGUuly0GUJ4dMY88dVG3Qufun5y4kN?= =?us-ascii?Q?HuojZRyqU3kro4nL0jDZe6kxLHs3vntq6p6MsZCuUY+/ohv0mKjhQ5p7bUiE?= =?us-ascii?Q?EPl91p8jAoFFGZIrpJ0XgIRKRjlP8jDM0lCqaHTRbQkbH2IQbaYkYRB91p0B?= =?us-ascii?Q?AAM1/DqUe4WB3LdppYJaGoZvbu7+fls8MzIo9/e326sLUr25GISPqx2+4pWP?= =?us-ascii?Q?C2WzraYtrMy39WD0hImabyRono+5u5o4TXS9zyZCT3hONHCDdfMJ7J58y67B?= =?us-ascii?Q?sflnBR44DhhHJSls5F6WS9WdwxQKOK6SsaREvMLjYN1jEi3kbO7UoyDK1wtm?= =?us-ascii?Q?Cq1iFoPYp5lawRJvAtrZyeOUqZquOxTYC1KoMvLhJQ9FCMfl5qWU2C7h5mBc?= =?us-ascii?Q?Tvq1FFe+Oh1sF2Ek5sU6W1/SI2vjwc02b/s/duQNJYB+PfcMnigRXMvWoL3/?= =?us-ascii?Q?8gEtved1HR21q6wDu0288SZ2tdEFNgETMIQ/TIGCwPjEZW5QSHvLDyNkSFO3?= =?us-ascii?Q?t9Q1tkC4jh9JfRHeerv0u70tKymNpOhPe9pH8G7V29OUngxjmffZWuGkS7cv?= =?us-ascii?Q?GRCa93h5uR15dX7aNf8=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0ee31673-81a9-4fc9-1dd4-08de2bae6b48 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Nov 2025 23:08:45.9538 (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: 31ljvTsRRhjsC1BLV7Xdctxc1M+zTzZWDxlqkfTpEXoBkswwgnqOmSCw9pQmNMbl X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR12MB8216 On Mon, Nov 24, 2025 at 02:43:58PM -0800, Nicolin Chen wrote: > On Mon, Nov 24, 2025 at 09:42:55PM +0000, Will Deacon wrote: > > On Sat, Nov 08, 2025 at 12:08:05AM -0800, Nicolin Chen wrote: > > > + /* Put the ids into order for sorted to_merge/to_unref arrays */ > > > + sort_nonatomic(fwspec->ids, fwspec->num_ids, > > > + sizeof(fwspec->ids[0]), arm_smmu_ids_cmp, NULL); > > > + /* ATS case adds num_ids of entries, on top of the base case */ > > > + master->build_invs = arm_smmu_invs_alloc(2 + fwspec->num_ids); > > > > Although I can't point at a specific issue here, I'm nervous about mutating > > the 'fwspec->ids' array from within the driver, The array isn't allocated > > or populated directly by the driver and so I don't think we really have any > > business sorting it. Could we hack iommu_fwspec_add_ids() to keep the array > > ordered instead? > > Yea, I think it makes sense to do it in the core, once we have the > data structure provided by the core as well. I would be more worried about sorting it everywhere for every driver. I feel confident SMMUv3 doesn't use it, but something really old and embedded focused like tegra or omap, IDK. So I wouldn't propose to change iommu_fwspec_add_ids(). If you want to be conservative then the thing to do is sort the master->streams that arm_smmu_insert_master() copies the fwspec into. It just has to be sorted prior to feeding it into the rbtree. Then consistently use master->streams as the sorted list. Jason