In the Linux kernel, the following vulnerability has been resolved: efi/fdt: fix panic when no valid fdt found setup_arch() would invoke efi_init()->efi_get_fdt_params(). If no valid fdt found then initial_boot_params will be null. So we should stop further fdt processing here. I encountered this issue on risc-v.
https://git.kernel.org/stable/c/8a7e8b4e5631a03ea2fee27957857a56612108ca
https://git.kernel.org/stable/c/668a84c1bfb2b3fd5a10847825a854d63fac7baa
https://git.kernel.org/stable/c/5148066edbdc89c6fe5bc419c31a5c22e5f83bdb