From: Lang Yu Lang.Yu@amd.com
[ Upstream commit 187916e6ed9d0c3b3abc27429f7a5f8c936bd1f0 ]
When using cpu to update page tables, vm update fences are unused. Install stub fence into these fence pointers instead of NULL to avoid NULL dereference when calling dma_fence_wait() on them.
Suggested-by: Christian König christian.koenig@amd.com Signed-off-by: Lang Yu Lang.Yu@amd.com Reviewed-by: Christian König christian.koenig@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index 924c6d5f86203..362fd43313552 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -2260,6 +2260,7 @@ struct amdgpu_bo_va *amdgpu_vm_bo_add(struct amdgpu_device *adev, amdgpu_vm_bo_base_init(&bo_va->base, vm, bo);
bo_va->ref_count = 1; + bo_va->last_pt_update = dma_fence_get_stub(); INIT_LIST_HEAD(&bo_va->valids); INIT_LIST_HEAD(&bo_va->invalids);
@@ -2962,7 +2963,8 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm) vm->update_funcs = &amdgpu_vm_cpu_funcs; else vm->update_funcs = &amdgpu_vm_sdma_funcs; - vm->last_update = NULL; + + vm->last_update = dma_fence_get_stub(); vm->last_unlocked = dma_fence_get_stub();
mutex_init(&vm->eviction_lock); @@ -3105,7 +3107,7 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm) vm->update_funcs = &amdgpu_vm_sdma_funcs; } dma_fence_put(vm->last_update); - vm->last_update = NULL; + vm->last_update = dma_fence_get_stub(); vm->is_compute_context = true;
/* Free the shadow bo for compute VM */