[PATCH v1 0/2] ACPI: PM: Fix up turning off unused power resources

[PATCH v1 0/2] ACPI: PM: Fix up turning off unused power resources

[Rafael J. Wysocki]

Hi,

This series fixes a regression introduced during the 5.14 cycle and related to
turning off unused ACPI power resources (patch [1/2]) and causes the states of
all power resources to be checked during initialization (patch [2/2]).

Please refer to the patch changelogs for details.

Thanks!

[PATCH v1 1/2] ACPI: PM: Do not turn off power resources in unknown state

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Commit 6381195ad7d0 ("ACPI: power: Rework turning off unused power
resources") caused power resources in unknown state with reference
counters equal to zero to be turned off too, but that caused issues
to appear in the field, so modify the code to only turn off power
resources that are known to be "on".

Link: https://lore.kernel.org/linux-acpi/6faf4b92-78d5-47a4-63df-cc2bab7769d0@molgen.mpg.de/
Fixes: 6381195ad7d0 ("ACPI: power: Rework turning off unused power resources")
Reported-by: Andreas K. Huettel <andreas.huettel@ur.de>
Tested-by: Andreas K. Huettel <andreas.huettel@ur.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 5.14+ <stable@vger.kernel.org> # 5.14+
---
 drivers/acpi/power.c |    7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

Index: linux-pm/drivers/acpi/power.c
===================================================================
--- linux-pm.orig/drivers/acpi/power.c
+++ linux-pm/drivers/acpi/power.c
@@ -1015,13 +1015,8 @@ void acpi_turn_off_unused_power_resource
 	list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
 		mutex_lock(&resource->resource_lock);
 
-		/*
-		 * Turn off power resources in an unknown state too, because the
-		 * platform firmware on some system expects the OS to turn off
-		 * power resources without any users unconditionally.
-		 */
 		if (!resource->ref_count &&
-		    resource->state != ACPI_POWER_RESOURCE_STATE_OFF) {
+		    resource->state == ACPI_POWER_RESOURCE_STATE_ON) {
 			acpi_handle_debug(resource->device.handle, "Turning OFF\n");
 			__acpi_power_off(resource);
 		}

[PATCH v1 2/2][RFT] ACPI: PM: Check states of power resources during initialization

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

To avoid situations in which the actual states of certain ACPI power
resources are not known just because they have never been referenced
by any device configuration objects, check the initial states of all
power resources as soon as they are found in the ACPI namespace (and
fall back to turning them on if the state check fails).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

Andreas, please test this patch (on top of the [1/2]) and let me know
if it works for you.

Thanks!

---
 drivers/acpi/power.c |   30 +++++++++++++-----------------
 1 file changed, 13 insertions(+), 17 deletions(-)

Index: linux-pm/drivers/acpi/power.c
===================================================================
--- linux-pm.orig/drivers/acpi/power.c
+++ linux-pm/drivers/acpi/power.c
@@ -923,6 +919,7 @@ struct acpi_device *acpi_add_power_resou
 	union acpi_object acpi_object;
 	struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
 	acpi_status status;
+	u8 state_dummy;
 	int result;
 
 	acpi_bus_get_device(handle, &device);
@@ -951,6 +948,10 @@ struct acpi_device *acpi_add_power_resou
 	resource->order = acpi_object.power_resource.resource_order;
 	resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
 
+	/* Get the initial state or just flip it on if that fails. */
+	if (acpi_power_get_state(resource, &state_dummy))
+		__acpi_power_on(resource);
+
 	pr_info("%s [%s]\n", acpi_device_name(device), acpi_device_bid(device));
 
 	device->flags.match_driver = true;

Re: [EXT] [PATCH v1 2/2][RFT] ACPI: PM: Check states of power resources during initialization

[Andreas K. Huettel]

[-- Attachment #1: Type: text/plain, Size: 1205 bytes --]

Am Freitag, 15. Oktober 2021, 19:14:10 CEST schrieb Rafael J. Wysocki:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> To avoid situations in which the actual states of certain ACPI power
> resources are not known just because they have never been referenced
> by any device configuration objects, check the initial states of all
> power resources as soon as they are found in the ACPI namespace (and
> fall back to turning them on if the state check fails).
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
> 
> Andreas, please test this patch (on top of the [1/2]) and let me know
> if it works for you.
> 

I see no negative impact (actually, no impact at all) of the second
additional patch. The network card is again working fine now.

Boot logs (unpatched, with one patch, with both patches) at
https://dev.gentoo.org/~dilfridge/igb/  (the 5.14.12* files).

Best,
Andreas

-- 
PD Dr. Andreas K. Huettel
Institute for Experimental and Applied Physics
University of Regensburg
93040 Regensburg
Germany

tel. +49 151 241 67748 (mobile)
tel. +49 941 943 1618 (office)
e-mail andreas.huettel@ur.de
http://www.akhuettel.de/
http://www.physik.uni-r.de/forschung/huettel/

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Re: [EXT] [PATCH v1 2/2][RFT] ACPI: PM: Check states of power resources during initialization

[Rafael J. Wysocki]

On Mon, Oct 18, 2021 at 12:41 PM Andreas K. Huettel
<andreas.huettel@ur.de> wrote:
>
> Am Freitag, 15. Oktober 2021, 19:14:10 CEST schrieb Rafael J. Wysocki:
> > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> >
> > To avoid situations in which the actual states of certain ACPI power
> > resources are not known just because they have never been referenced
> > by any device configuration objects, check the initial states of all
> > power resources as soon as they are found in the ACPI namespace (and
> > fall back to turning them on if the state check fails).
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > ---
> >
> > Andreas, please test this patch (on top of the [1/2]) and let me know
> > if it works for you.
> >
>
> I see no negative impact (actually, no impact at all) of the second
> additional patch. The network card is again working fine now.
>
> Boot logs (unpatched, with one patch, with both patches) at
> https://dev.gentoo.org/~dilfridge/igb/  (the 5.14.12* files).

Thanks!