From: Al Stone al.stone@linaro.org
Per the ACPI 5.0 specification, section 5.2.9, none of the power management fields in the FADT are to be used. Short-circuit using any of those fields in acpi_processor_get_power_info_fadt().
Signed-off-by: Al Stone al.stone@linaro.org --- drivers/acpi/processor_idle.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index eac984a..89f0a0f 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -270,6 +270,14 @@ static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) if (!pr->pblk) return -ENODEV;
+ /* + * Using power management information from the FADT is not + * allowed when in HW reduced mode. See ACPI 5.0, section + * 5.2.9. + */ + if (acpi_gbl_reduced_hardware) + return -ENODEV; + /* if info is obtained from pblk/fadt, type equals state */ pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3;