Am 2021-09-20 um 5:55 p.m. schrieb Philip Yang:
> Don't use devm_request_free_mem_region to alloc VRAM region for pgmap,
devm_... refers to a device manager that automatically releases
device-specific resources when a driver disconnects from a device. So
maybe that just means, our devm_memunmap_pages and
devm_release_mem_region calls in svm_migrate_fini are redundant, and the
best solution is to remove those calls.
See Documentation/driver-api/driver-model/devres.rst
Regards,
Felix
> because driver__detach releases all device resource region, then calls
> amdgpu_device_fini_sw, which calls devm_memunmap_pages generating below
> warning trace:
>
> WARNING: CPU: 1 PID: 3646 at drivers/base/devres.c:795
> devm_release_action+0x51/0x60
> Call Trace:
> ? memunmap_pages+0x360/0x360
> svm_migrate_fini+0x2d/0x60 [amdgpu]
> kgd2kfd_device_exit+0x23/0xa0 [amdgpu]
> amdgpu_amdkfd_device_fini_sw+0x1d/0x30 [amdgpu]
> amdgpu_device_fini_sw+0x45/0x290 [amdgpu]
> amdgpu_driver_release_kms+0x12/0x30 [amdgpu]
> drm_dev_release+0x20/0x40 [drm]
> release_nodes+0x196/0x1e0
> device_release_driver_internal+0x104/0x1d0
> driver_detach+0x47/0x90
> bus_remove_driver+0x7a/0xd0
> pci_unregister_driver+0x3d/0x90
> amdgpu_exit+0x11/0x20 [amdgpu]
> Trying to free nonexistent resource <000007fc00000000-000007fdffffffff>
>
> Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 13 ++++++-------
> 1 file changed, 6 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
> index 21f745e0b86c..aa96767920a9 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
> @@ -880,7 +880,7 @@ int svm_migrate_init(struct amdgpu_device *adev)
> * should remove reserved size
> */
> size = ALIGN(adev->gmc.real_vram_size, 2ULL << 20);
> - res = devm_request_free_mem_region(adev->dev, &iomem_resource, size);
> + res = request_free_mem_region(&iomem_resource, size, "amdgpu_vram");
> if (IS_ERR(res))
> return -ENOMEM;
>
> @@ -891,14 +891,13 @@ int svm_migrate_init(struct amdgpu_device *adev)
> pgmap->ops = &svm_migrate_pgmap_ops;
> pgmap->owner = SVM_ADEV_PGMAP_OWNER(adev);
> pgmap->flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE;
> - r = devm_memremap_pages(adev->dev, pgmap);
> + r = memremap_pages(pgmap, dev_to_node(adev->dev));
> if (IS_ERR(r)) {
> pr_err("failed to register HMM device memory\n");
>
> /* Disable SVM support capability */
> pgmap->type = 0;
> - devm_release_mem_region(adev->dev, res->start,
> - res->end - res->start + 1);
> + release_mem_region(res->start, res->end - res->start + 1);
> return PTR_ERR(r);
> }
>
> @@ -919,7 +918,7 @@ void svm_migrate_fini(struct amdgpu_device *adev)
> if (!KFD_IS_SVM_API_SUPPORTED(adev->kfd.dev))
> return;
>
> - devm_memunmap_pages(adev->dev, pgmap);
> - devm_release_mem_region(adev->dev, pgmap->range.start,
> - pgmap->range.end - pgmap->range.start + 1);
> + memunmap_pages(pgmap);
> + release_mem_region(pgmap->range.start,
> + pgmap->range.end - pgmap->range.start + 1);
> }
