Without cpu hotplug support, vCPU cannot be removed from a Service VM. Don't expose remove_cpu sysfs when CONFIG_HOTPLUG_CPU disabled. Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Qais Yousef <qais.yousef@arm.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Shuo Liu <shuo.a.liu@intel.com> Link: https://lore.kernel.org/r/20210221134339.57851-2-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>