diff options
| author | Felix Kuehling <Felix.Kuehling@amd.com> | 2019-08-30 00:10:34 -0400 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2019-09-13 17:49:38 -0500 |
| commit | cd05c865108e089c4be99c0f939c72437fba2207 (patch) | |
| tree | 2ef6e7d817f94b11093471f69176c5b93173bcda /drivers | |
| parent | 811bc15b49fe2dde87b9109b5eeea8ebe6420c79 (diff) | |
| download | linux-cd05c865108e089c4be99c0f939c72437fba2207.tar.bz2 | |
drm/amdgpu: Disable page faults while reading user wptrs
These wptrs must be pinned and GPU accessible when this is called
from hqd_load functions. So they should never fault. This resolves
a circular lock dependency issue involving four locks including the
DQM lock and mmap_sem.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Oak Zeng <Oak.Zeng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h index 1af8f83f7e02..c003d9275837 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h @@ -179,10 +179,17 @@ uint64_t amdgpu_amdkfd_get_mmio_remap_phys_addr(struct kgd_dev *kgd); uint32_t amdgpu_amdkfd_get_num_gws(struct kgd_dev *kgd); uint8_t amdgpu_amdkfd_get_xgmi_hops_count(struct kgd_dev *dst, struct kgd_dev *src); +/* Read user wptr from a specified user address space with page fault + * disabled. The memory must be pinned and mapped to the hardware when + * this is called in hqd_load functions, so it should never fault in + * the first place. This resolves a circular lock dependency involving + * four locks, including the DQM lock and mmap_sem. + */ #define read_user_wptr(mmptr, wptr, dst) \ ({ \ bool valid = false; \ if ((mmptr) && (wptr)) { \ + pagefault_disable(); \ if ((mmptr) == current->mm) { \ valid = !get_user((dst), (wptr)); \ } else if (current->mm == NULL) { \ @@ -190,6 +197,7 @@ uint8_t amdgpu_amdkfd_get_xgmi_hops_count(struct kgd_dev *dst, struct kgd_dev *s valid = !get_user((dst), (wptr)); \ unuse_mm(mmptr); \ } \ + pagefault_enable(); \ } \ valid; \ }) |