From: Ville Syrjälä ville.syrjala@linux.intel.com
commit d6b88ce2eb9d ("ACPI: processor idle: Allow playing dead in C3 state") was supposedly just trying to enable C3 when the CPU is offlined, but it also mistakenly enabled C3 usage without setting ARB_DIS=1 in normal idle scenarios.
This results in a machine that won't boot past the point when it first enters C3. Restore the correct behaviour (either demote to C1/C2, or use C3 but also set ARB_DIS=1).
I hit this on a Fujitsu Siemens Lifebook S6010 (P3) machine.
Cc: stable@vger.kernel.org Cc: Woody Suwalski wsuwalski@gmail.com Cc: Mario Limonciello mario.limonciello@amd.com Cc: Richard Gong richard.gong@amd.com Cc: Rafael J. Wysocki rafael.j.wysocki@intel.com Fixes: d6b88ce2eb9d ("ACPI: processor idle: Allow playing dead in C3 state") Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com --- v2: Paint it in a different color (Rafael)
drivers/acpi/processor_idle.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 4556c86c3465..5f296e099bce 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -795,7 +795,8 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr) if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 || cx->type == ACPI_STATE_C3) { state->enter_dead = acpi_idle_play_dead; - drv->safe_state_index = count; + if (cx->type != ACPI_STATE_C3) + drv->safe_state_index = count; } /* * Halt-induced C1 is not good for ->enter_s2idle, because it