Hi Christian, I don't know much about the background. But according to my experiments, as long as we change the vm size to 64G, ATC memory access on Raven will fall apart. How should deal with that or can you come up with a fix? Regards, Yong On 2017-12-14 03:47 AM, Christian König wrote: > NAK, that really circumvents the intention of the patch to adjust the > number of levels based on the vm_size. > > Christian. > > Am 14.12.2017 um 03:25 schrieb Yong Zhao: >> Change-Id: Id522c1cbadb8c069720f4e64a31cff42cd014733 >> Signed-off-by: Yong Zhao <yong.zhao at amd.com> >> --- >>  drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 2 +- >>  1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> index 709587d..3b9eb1a 100644 >> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c >> @@ -2534,7 +2534,7 @@ void amdgpu_vm_adjust_size(struct amdgpu_device >> *adev, uint32_t vm_size, >>      uint64_t tmp; >>       /* adjust vm size first */ >> -   if (amdgpu_vm_size != -1) { >> +   if (amdgpu_vm_size != -1 && max_level == 1) { >>          unsigned max_size = 1 << (max_bits - 30); >>           vm_size = amdgpu_vm_size; >