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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?+ve+2ZcdU1px9uuySyTYmU74EsxcytfuPF6V1VX3YEt/WRD7PuuZs6Uv9v5W?= =?us-ascii?Q?4CQsDXaezYawspgbEiCSmie+xTr32+jmCAnejyoeWG2vTX7o7nHtOEkoP2vm?= =?us-ascii?Q?S42N3RGJroH8FiY5Wv9hZe1TgCsKq+SAfcFTOka3BaoQBaVjddQSKG1r/B8y?= =?us-ascii?Q?P3xthNv/3ZjQpMFspgD+XmuaatOp/uRzIbfoG22ryjEMNGhX/+3rNOYFFFmA?= =?us-ascii?Q?ZXKC6g65cvSqHk6ovg31vMmJ9RQQ4YZul6aM8qtwA3a5uvy16YL3Ksix68Lk?= =?us-ascii?Q?HN+So2f8fTjEtzuastOtTFAGnKeKfJ616KM06TlkYMDBwIuEGWlurEsb3jm7?= =?us-ascii?Q?iw/8R34HoFm4RTRlF0vCzw+ASdnY6S3YbUZYez8kF3jAzRWQjr60iNT48jXW?= =?us-ascii?Q?ZOd8lXgoW6BkhM6VXyCt2XRcv41jntBapwZZuLPjh7GAYFSTNt1apw/Nn1bi?= =?us-ascii?Q?5HP7hAQeh8OpAcvvUpfm73InmgVMl9PT+1AFhjmMrihNJrJQrasOmdPdNW69?= =?us-ascii?Q?uqgcFZLVn6NwlLuDd35AIV4bFWTGY8kQoW4hWrqLwJrMGJJtgGSfIsC3J4Xj?= =?us-ascii?Q?L5Aq2MEKW9IGZB8OoZSu3PSF5jJM0SuyFENAY9dqe/JphU03DZpsv3LX7Fv8?= =?us-ascii?Q?gZHRj43/zhTDvIjsSmmUAQC88yF7/82lvsywNkeBF3BF0uE442LA6Ox38lxl?= =?us-ascii?Q?U1iVOP3NaG8/+ox4rN2/dP06UwghrmTKBAM1a74GXja0Co8LCyJuRSo934Gq?= =?us-ascii?Q?o7OkXNF+dMrk9sSVtNk9yCjh5Ie0KF6HzmsGCSee89VcAXBkrU1ofUsUu34K?= =?us-ascii?Q?uQBojDwjGsCzNzF81exw27dcNWEDJldDlPnGCWNGJD/WU0VC30eU6Y6RthbB?= =?us-ascii?Q?ye/DrZ5+D5bvxe3J3ni4dURLHPNcsAFzBo7DwMTrjOrBuG3kA+MyFodYVHfr?= =?us-ascii?Q?yAfms7G0oIBd7laLZukTeZtpz2cv1wZ/yW4M8cU3QNvcattvR+DDNJtYTWcH?= =?us-ascii?Q?n7s4x0DDwny/zzYoTgwc6zJcWxUu/rAXIeVA4svWckgFdLEfhCwoJoHSy268?= =?us-ascii?Q?ikJRD2RCHSSaZYLntPjPvtQi5EZlN9jc2dze882l535pFtqXneIJd98QtRBJ?= =?us-ascii?Q?U9PsrnzQZMuuw54jNWrmqsquHrw/sBmacBmI2PVKcq04ug2ZsXwo+js5LYV2?= =?us-ascii?Q?c4RplzVz7ou4WWokQxvy8w7561HArYduNKzMjzGwqq6AnL95ycoWdWe9HWNL?= =?us-ascii?Q?BmWBWUhyTsn3ioF3Zm5tLuGJERuJ2b9Wi4z3VGqUjiL/qA+n+wlIiougHgHT?= =?us-ascii?Q?t70tbedlneWNQ6GMvVZatWTKfgVJr0kPlbN0dIrw4a6QbZjKAj5zL3ce4QE1?= =?us-ascii?Q?k7a1zKaPKzD4vzuf89QGHcAQQ1MM5lerxEj7rni5LLZdpeWL2cZAc9+R8JCh?= =?us-ascii?Q?C8QIFDZZgjQjCRM5H7a6fQS2D0hdxZqJefxnzDKjVGgW+ZmybkKt0K0Skcsm?= =?us-ascii?Q?WvsvT8DAYQ7clnRdGYCKyE4S2fio3kyvCmHEnVkYTGRtD3qEnof85UQnGCKc?= =?us-ascii?Q?X7q7DqmkyqtTXmYb1qNVhJ8R9hMWVUFx//k9sH8K?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 17933af4-8dc8-4e5c-d31c-08db2caaf181 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Mar 2023 21:01:31.2343 (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: FAXoWmYwF6qoJ4rYs5RUp19yGZ+Sodatqgn1ewTPsm8i7WjlGLoNQGTFNSEYvImJ X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4343 On Thu, Oct 27, 2022 at 10:59:04AM -0300, Jason Gunthorpe wrote: > I'm seeing this at every boot, on v6.1-rc2 > > I've just realized it means lockdep is turned off for the actual > testing I want to do. Very annoying > > Lu, is there a solution yet? I saw some patches for a different > lockdep splat but not this one. > > [ 0.604492] ====================================================== > [ 0.604838] WARNING: possible circular locking dependency detected > [ 0.605221] 6.1.0-rc2+ #24 Not tainted > [ 0.605432] ------------------------------------------------------ > [ 0.605734] swapper/0/1 is trying to acquire lock: > [ 0.605985] ffff8880069ab8a0 (&md->mutex){+.+.}-{3:3}, at: msi_get_virq+0x99/0x150 > [ 0.606281] > [ 0.606281] but task is already holding lock: > [ 0.606281] ffffffff82676890 (cpu_hotplug_lock){++++}-{0:0}, at: init_vqs+0x6db/0x940 > [ 0.606281] > [ 0.606281] which lock already depends on the new lock. Lu, did you ever figure this out? It still happens. It is because dmar_global_lock is held while calling iommu_device_register() and also held during intel_irq_remapping_alloc() iommu_device_register() eventually obtains the cpu_hotplug_lock to setup the DMA API intel_irq_remapping_alloc() is called by drivers under the cpu_hotplug_lock to setup their interrupts To fix it you cannot use the same lock in both places Jason