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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?qAi9og+pfm6U99LIGNir2YUS+eRGw7ZvAUmFQBdd35a44DskWPXmqDWCYkpJ?= =?us-ascii?Q?mMsqqy2Gjb69dZRbZuoQwoqaKsAPI3qFrHstXgaqHMXymIUFe2GLbqRzuabl?= =?us-ascii?Q?MzymVtjm2ugMbOWW5X/EYTn8TnFSdfvnjPLVYLg0GGSDLkiBNp7pbLAo0DCx?= =?us-ascii?Q?NOG8BqgLsTAWn5E/bfte8ilRtKjOI3g+VV9n1C5aflVoOZALNraRvUHIoOJ+?= =?us-ascii?Q?/429U/EGa7qT9uLbYNm2a42yUlLidaqUUoiY2bfY1hEwfXqqb+DwqZB0eP+W?= =?us-ascii?Q?A+lFN420uR3AAW6ZzSeVg1d+Lr8Sa1lIUFRCES0S+SaefH16o9Wb3ePCJSND?= =?us-ascii?Q?lc0E3afJ/kD988pdAm/cCQUkKx/WkCwSfZW0DGDvw1k0GZnuWg32Ylz3HQJx?= =?us-ascii?Q?MjFCYmDX3N/T+VNebFm/rLoCj05ufqiEod/isd7PqWlXXxmzrCQad7EfDjah?= =?us-ascii?Q?ot6274mekgbi7g0no+VGn5I/v2l9BAwrL147vgkh9zFeLqrhC7lgofcgJWwh?= =?us-ascii?Q?lmoMFd0ChLv7DKM5jDUN9NMAtJoOJBpoXpAGYzXZn4pNiANlAKNN5sCjuJDP?= =?us-ascii?Q?c3hTuNDMgXIZQCfFMOWehwqs2h/NJ1j1ZO3+unPZjxEwH8leeq9KAlHwZWvf?= =?us-ascii?Q?8ks2CvbjvZTdm4oSXHYO8e6CPXTQfhkKL2kdJTC0A40Ov2k1N1NnhopZlEGv?= =?us-ascii?Q?HRKWn2lFGsW8Ejk73ov6BHyy5J7GtBjbku5cjbgK5v/Bb9DKfQTbscXTzn22?= =?us-ascii?Q?CjDl1uV4aVz9cGXxUTVExXJdklqkOlZsR553AJIfV5dExpgixZcXkaahK0Ml?= =?us-ascii?Q?U6wvWe2Z9NxxulGaQDYoLJr2S+6sNgnDFKFJy1g9fGHyOD7lwdeWmEJUOU3V?= =?us-ascii?Q?01sNFIfzZxCic+0evBeQYEEolQtmgiGvC2nX3jDs70xa+V9l1r7C+dBPWhZQ?= =?us-ascii?Q?xXya5IDg+Jv8pwr4+BVd2rbFk1OppdSgqpCCx2Ohw1vCxrxTQ1VkMrHfPXd/?= =?us-ascii?Q?gS3/bVXesbVM3Ekoi7s7qjnvcM7KqNqjqR4u1pancFvx3gbpKuqCRRcyhsHx?= =?us-ascii?Q?1rxi/rzpRyrMj1wGbynSk7eCACPJMnuJLGkczDJ6fBLRiv22h3rAW13pfRib?= =?us-ascii?Q?I2wpGTtx4ni8tUzSZadyN/Rz+z5BzdL1T/fLqfMIN2aFYEJNqWK6p9vmnJS9?= =?us-ascii?Q?WEUXS/o0ngK+Lejaci5+o9Qk3N6DkQl1AMPdPPJIvqm98T+cvQ6fIHQ1rxml?= =?us-ascii?Q?z8mzf57IPKI3sxfpGc/guaAzZJ8OakLJD/ZLkTtkrm0VlxJ/9okqWEeR/P4o?= =?us-ascii?Q?v4coovlVTpmqMGMTqoK5IjuDeN31VrVDteDwzdnqM4SN4ZBVaayxzNGpIOvC?= =?us-ascii?Q?AcFgbYx6KAfQ6tJnEhlAaDjof0ggRN+K38EMClB+CAJvvpSCARBJfd8iM+s8?= =?us-ascii?Q?D4Mx5pqjapWzasByaiqWITbwBco/XK+MWLpGE/WBK5hJIqIF+B+QvNK+TlS8?= =?us-ascii?Q?p1sQLZLUNE54mzOzsH2B2AYkeytLK5BrVnMSH0tJ2NISO2L0EXADZbGYY23F?= =?us-ascii?Q?k73rnKfhJ9NbzfXWQQ8sLdcX4xTdxDfJTyQz3R2NJalxhV8RzCZbsvBxNPpX?= =?us-ascii?Q?H1Ae0Vhb/c/AUc9t0OkO5YhDH+6qQgxk+5Y+60UeCAAmhkn7tUXzvZyRWXWR?= =?us-ascii?Q?iuxYWqTYxKsdt7MNHCsPillvpFBWI/ennqp7j/65lffHEd3L?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 84c63572-8fdd-4133-6c5a-08dedb173f6d X-MS-Exchange-CrossTenant-AuthSource: DS0PR12MB7726.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jul 2026 04:30:02.9457 (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: 2gloE7A8Tz12a3wn+Hpmq8W69x7A42zsovMDKCMjb5KgF86No/tGekGzaAG/ik0zKxBVKm81ofvEQvKY7TeCPg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6780 On 2026-06-30 at 09:30 +1000, Stanislav Kinsburskii wrote... > Commit af69016dab96 ("lib: test_hmm: implement a device release method") > moved the initial dmirror_allocate_chunk() call before cdev_device_add(). > That means the struct cdev has not been added yet, so cdev_add() has not > initialized mdevice->cdevice.dev. > > The coherent-device range selection uses the device minor to choose between > spm_addr_dev0 and spm_addr_dev1. Reading MINOR(mdevice->cdevice.dev) before > cdev_add() therefore always sees an uninitialized dev_t. As a result, both > coherent devices select the same physical range, and adding the second > device fails due to the overlapping dev_pagemap range. > > Use mdevice->device.devt instead. It is initialized in > dmirror_device_init() before dmirror_allocate_chunk() is called and is the > same dev_t later passed to cdev_device_add(). > > Fixes: af69016dab96 ("lib: test_hmm: implement a device release method") > Signed-off-by: Stanislav Kinsburskii > --- > lib/test_hmm.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/lib/test_hmm.c b/lib/test_hmm.c > index 9c59d1ceb5b5..c4adbf98fac7 100644 > --- a/lib/test_hmm.c > +++ b/lib/test_hmm.c > @@ -581,7 +581,7 @@ static int dmirror_allocate_chunk(struct dmirror_device *mdevice, > devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; > break; > case HMM_DMIRROR_MEMORY_DEVICE_COHERENT: > - devmem->pagemap.range.start = (MINOR(mdevice->cdevice.dev) - 2) ? > + devmem->pagemap.range.start = (MINOR(mdevice->device.devt) - 2) ? Makes sense to me. As Andrew mentioned we should cc: stable, but I assume he will add that so: Reviewed-by: Alistair Popple > spm_addr_dev0 : > spm_addr_dev1; > devmem->pagemap.range.end = devmem->pagemap.range.start + > > >