+ mr->destructor = memory_region_destructor_ram;
+ mr->dirty_log_mask = tcg_enabled() ? (1 << DIRTY_MEMORY_CODE) : 0;
+ /* qemu_ram_alloc_from_ptr cannot fail with ptr != NULL. */
+ assert(ptr != NULL);
+ mr->ram_block = qemu_ram_alloc_from_ptr(size, ptr, mr, &error_fatal);