A quick-and-dirty fix is reloading the kernel module "acpi_cpufreq": $ modprobe -rv acpi_cpufreq $ modprobe -v acpi_cpufreq
A quick-and-dirty fix is reloading the kernel module "acpi_cpufreq":
$ modprobe -rv acpi_cpufreq
$ modprobe -v acpi_cpufreq