drm/amdgpu: fix potential VM faults

[ Upstream commit 3122051edc7c27cc08534be730f4c7c180919b8a ]

When we allocate new page tables under memory
pressure we should not evict old ones.
Signed-off-by: NChristian König <christian.koenig@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_object.c

@@ -428,7 +428,8 @@ static int amdgpu_bo_do_create(struct amdgpu_device *adev,
 		.interruptible = (bp->type != ttm_bo_type_kernel),
 		.no_wait_gpu = false,
 		.resv = bp->resv,
-		.flags = TTM_OPT_FLAG_ALLOW_RES_EVICT
+		.flags = bp->type != ttm_bo_type_kernel ?
+			TTM_OPT_FLAG_ALLOW_RES_EVICT : 0
 	};
 	struct amdgpu_bo *bo;
 	unsigned long page_align, size = bp->size;