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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: vWvPJIt6ScJUqknLxSQy7R4E4NdWVSRtoTgxj2j3Sy15Bw3kY/rC+dzrKiSFG/b6tgcLcUa8jmgx1DV887lCcqea7I8oahMyxR6eOiQOVjeKXytyLztPFuEFd2vU5GMDyJM147TZcn+1PThX5fS7Wn1LZ7m1hMm25amiIZf9gaLLveXOWu6CXzCGWTJGHwyYkB1zuO2ExgdRb5M8U/zM7lbcBOVTQtWJI7l4jV0H6+SWpiby2oKBTXTURO200BhsJozFOyr1oPCw9RWi/HHV5F/xeyYyueZbYQQ72FUtpq71IRybjfnOGQBqqrGRnSLt2ky0A1L9XKyVpoSoVLQHm6uCMVVrKEWVQu2J1yGXPH04ms1osgHJdr4pftRNxUHEljmpUaf+sY0sMNvrwviR8P2HVC5rOHB3hSR/hRYGLPYiRXWorPduKxfmT9JEQSSq X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Apr 2026 13:33:30.0488 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 09e8c89a-cc4b-4a84-af1a-08dea073bdf7 X-MS-Exchange-CrossTenant-Id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=f34e5979-57d9-4aaa-ad4d-b122a662184d;Ip=[4.158.2.129];Helo=[outbound-uk1.az.dlp.m.darktrace.com] X-MS-Exchange-CrossTenant-AuthSource: DU2PEPF00028D07.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM0PR08MB5410 Hi All, > > On Tue, Apr 21, 2026 at 07:57:43AM +0100, Yeoreum Yun wrote: > > > > [...] > > > > > > > > Also, the FF-A initialization is not driven by a device probe, but rather > > > happens as part of the bus registration itself, > > > so it does not fit well with a device_link or probe deferral based approach. > > > > > > Instead, perhaps we could go with the idea I mentioned previously: > > > either introduce a notifier, or create a pseudo ffa_device > > > once pKVM initialization has completed, and > > > then let the ffa driver perform the additional initialization from there. > > > > > > Am I missing something? > > > > > > > In order to handle/cleanup some ugliness in interrupt management in the > > FF-A driver, we may introduce DT node eventually. But it will take sometime. > > Unfortunately, I think this DT node wouldn't be helpful to solve > this situation for dependency with the kvm misc device... > > IMHO, current situation, the notifier seems to good option. unless > we make the initcall to recongise this dependency. > I think the best approach for now is to introduce a notifier to handle this situation. If there are no further suggestions, I’ll send a v2 based on: - https://lore.kernel.org/all/aeS4rAeVQ0yJIPYw@e129823.arm.com/ Thanks! -- Sincerely, Yeoreum Yun