The `initialize_identity_maps` function is defined in the [arch/x86/boot/compressed/kaslr_64.c](https://github.com/torvalds/linux/blob/v4.16/arch/x86/boot/compressed/kaslr_64.c) source code file. This function starts by initialising an instance of the `x86_mapping_info` structure called `mapping_info`:
The `initialize_identity_maps` function is defined in the [arch/x86/boot/compressed/kaslr_64.c](https://github.com/torvalds/linux/blob/master/arch/x86/boot/compressed/kaslr_64.c) source code file. This function starts by initialising an instance of the `x86_mapping_info` structure called `mapping_info`: