[PATCH] drm/amdgpu: Forbid kfd using cpu to update pt if vm is shared with gfx

[YuBiao Wang]

If a same GPU VM is shared by kfd and graphic operations, we must align
the vm update mode to sdma, or cpu kmap will fail and cause null pointer
issue.

Signed-off-by: YuBiao Wang <YuBiao.Wang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 291977b93b1d..e105ff9e8041 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -2239,6 +2239,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 {
 	bool pte_support_ats = (adev->asic_type == CHIP_RAVEN);
+	struct amdgpu_bo *bo = vm->root.bo;
 	int r;
 
 	r = amdgpu_bo_reserve(vm->root.bo, true);
@@ -2265,6 +2266,10 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 	/* Update VM state */
 	vm->use_cpu_for_update = !!(adev->vm_manager.vm_update_mode &
 				    AMDGPU_VM_USE_CPU_FOR_COMPUTE);
+
+	if (bo && !(bo->flags & AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED))
+		vm->use_cpu_for_update = false;
+
 	DRM_DEBUG_DRIVER("VM update mode is %s\n",
 			 vm->use_cpu_for_update ? "CPU" : "SDMA");
 	WARN_ONCE((vm->use_cpu_for_update &&
-- 
2.34.1