+ mtx_init(&shim_device.mem_lock, mtx_plain);
+
+ shim_device.mem_fd = memfd_create("shim mem", MFD_CLOEXEC);
+ assert(shim_device.mem_fd != -1);
+
+ ASSERTED int ret = ftruncate(shim_device.mem_fd, SHIM_MEM_SIZE);
+ assert(ret == 0);
+
+ util_vma_heap_init(&shim_device.mem_heap, 4096, SHIM_MEM_SIZE - 4096);
+