From: Lang Yu <Lang.Yu@xxxxxxx> [ 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@xxxxxxx> Signed-off-by: Lang Yu <Lang.Yu@xxxxxxx> Reviewed-by: Christian König <christian.koenig@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 003aa9e47085e..2fa7b68c5966d 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -1352,6 +1352,7 @@ 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); @@ -2061,7 +2062,8 @@ 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(); vm->last_tlb_flush = dma_fence_get_stub(); @@ -2186,7 +2188,7 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm) goto unreserve_bo; 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 */ -- 2.39.2
