Rafael J. Wysocki wrote:
On Wed, Apr 20, 2022 at 3:44 PM Ville Syrjala
<ville.syrjala@xxxxxxxxxxxxxxx> wrote:
From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Cc: Woody Suwalski <wsuwalski@xxxxxxxxx>
Cc: Mario Limonciello <mario.limonciello@xxxxxxx>
Cc: Richard Gong <richard.gong@xxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Fixes: d6b88ce2eb9d ("ACPI: processor idle: Allow playing dead in C3 state")
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/acpi/processor_idle.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 4556c86c3465..54f0a1915025 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -793,10 +793,10 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr)
state->flags = 0;
if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 ||
- cx->type == ACPI_STATE_C3) {
+ cx->type == ACPI_STATE_C3)
state->enter_dead = acpi_idle_play_dead;
+ if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2)
drv->safe_state_index = count;
- }
/*
* Halt-induced C1 is not good for ->enter_s2idle, because it
* re-enables interrupts on exit. Moreover, C1 is generally not
--
Good catch, but I would prefer doing the below which should be
equivalent (modulo GMail-induced white space breakage):
---
drivers/acpi/processor_idle.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
Index: linux-pm/drivers/acpi/processor_idle.c
===================================================================
--- linux-pm.orig/drivers/acpi/processor_idle.c
+++ linux-pm/drivers/acpi/processor_idle.c
@@ -795,7 +795,8 @@ static int acpi_processor_setup_cstates(
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
I have tested both solutions from Ville and Rafael, and both work OK on T40.
Clearly, since Ville has duped the issue on a non-T40 machine, the
processor_power_dmi_table[] solution is incorrect.
Rafael's solution seems simpler - so I also like it more :-)
Thanks, Woody
