Hi David, your commit 9861908f081f ("MIPS: OCTEON: Enable little endian kernel.") adds the following conditional select to arch/mips/Kconfig: + select SYS_SUPPORTS_HOTPLUG_CPU if CONFIG_CPU_BIG_ENDIAN The problem is the 'CONFIG_' prefix for 'CPU_BIG_ENDIAN'. The item is always off since the prefix does not work as we are in a Kconfig file. Hence, the if-statement never evaluates to true. It can be fixed by simply removing the 'CONFIG_' prefix. I detected this commit with ./scripts/checkkconfigsymbols.py. Commit b1a3f243485f ("checkkconfigsymbols.py: make it Git aware") added support to check (and compare) undefined Kconfig symbols in Git commits. Kind regards, Valentin