* [PATCH v6 1/2] PM: sleep: Rename module parameters prefix to "pm"
2026-07-08 4:33 [PATCH v6 0/2] PM: dpm_watchdog: Improve DPM watchdog configurability Tzung-Bi Shih
@ 2026-07-08 4:33 ` Tzung-Bi Shih
2026-07-08 4:33 ` [PATCH v6 2/2] PM: dpm_watchdog: Allow disabling DPM watchdog by default Tzung-Bi Shih
1 sibling, 0 replies; 3+ messages in thread
From: Tzung-Bi Shih @ 2026-07-08 4:33 UTC (permalink / raw)
To: Jonathan Corbet, Rafael J. Wysocki, Greg Kroah-Hartman,
Danilo Krummrich
Cc: Shuah Khan, Pavel Machek, Len Brown, tzungbi, linux-doc,
linux-kernel, linux-pm, driver-core, tfiga, senozhatsky,
Randy Dunlap
Currently, the module parameters defined in drivers/base/power/main.c
use the default prefix "main" (derived from the filename). The prefix
is too generic and non-descriptive.
Redefine MODULE_PARAM_PREFIX to "pm." to group the module
parameters under the namespace instead. This makes the parameters more
descriptive.
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
v6:
- Change the prefix "pm_sleep" -> "pm".
v5: https://lore.kernel.org/all/20260701045640.3130090-2-tzungbi@kernel.org
- No changes.
v4: https://lore.kernel.org/all/20260611021219.2093476-2-tzungbi@kernel.org
- "power" -> "pm_sleep".
v3: https://lore.kernel.org/all/20260608021526.1023248-2-tzungbi@kernel.org
- No changes.
v2: https://lore.kernel.org/all/20260604090756.2884671-2-tzungbi@kernel.org
- New to the series.
v1: Doesn't exist.
---
drivers/base/power/main.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index f71467f6ada4..49ea6e2cd735 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -41,6 +41,9 @@
#include "../base.h"
#include "power.h"
+#undef MODULE_PARAM_PREFIX
+#define MODULE_PARAM_PREFIX "pm."
+
typedef int (*pm_callback_t)(struct device *);
/*
--
2.55.0.795.g602f6c329a-goog
^ permalink raw reply related [flat|nested] 3+ messages in thread
* [PATCH v6 2/2] PM: dpm_watchdog: Allow disabling DPM watchdog by default
2026-07-08 4:33 [PATCH v6 0/2] PM: dpm_watchdog: Improve DPM watchdog configurability Tzung-Bi Shih
2026-07-08 4:33 ` [PATCH v6 1/2] PM: sleep: Rename module parameters prefix to "pm" Tzung-Bi Shih
@ 2026-07-08 4:33 ` Tzung-Bi Shih
1 sibling, 0 replies; 3+ messages in thread
From: Tzung-Bi Shih @ 2026-07-08 4:33 UTC (permalink / raw)
To: Jonathan Corbet, Rafael J. Wysocki, Greg Kroah-Hartman,
Danilo Krummrich
Cc: Shuah Khan, Pavel Machek, Len Brown, tzungbi, linux-doc,
linux-kernel, linux-pm, driver-core, tfiga, senozhatsky,
Randy Dunlap
Introduce the "dpm_watchdog_enabled" module parameter to allow the DPM
watchdog to be enabled or disabled at boot time and runtime.
Additionally, introduce the CONFIG_DPM_WATCHDOG_ENABLED Kconfig option
to set the default value of the module parameter at compile time.
The primary motivation for this configurability resolves around Android
GKI (Generic Kernel Image). We want to enable CONFIG_DPM_WATCHDOG in
the GKI so the feature is available. However, because the GKI is shared
across many different devices, we don't want to inadvertently affect
devices that are unaware of this feature. This provides a way to
compile it in, but keep it disabled by default for those devices via the
kernel command line or module parameters.
To maintain backward compatibility, CONFIG_DPM_WATCHDOG_ENABLED relies
on `default y`. Previously, the DPM watchdog was always active if
CONFIG_DPM_WATCHDOG was set. Defaulting this new option to 'y' ensures
that the behavior remains unchanged for existing users and defconfigs
when they upgrade.
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
v6:
- Change the prefix "pm_sleep" -> "pm".
v5: https://lore.kernel.org/all/20260701045640.3130090-3-tzungbi@kernel.org
- No changes.
v4: https://lore.kernel.org/all/20260611021219.2093476-3-tzungbi@kernel.org
- Rewrite the commit message to indicate the module parameter is the
main change in the patch.
- DPM_WATCHDOG_DEFAULT_ENABLED -> DPM_WATCHDOG_ENABLED.
v3: https://lore.kernel.org/all/20260608021526.1023248-3-tzungbi@kernel.org
- Add "PM" tag (was missing).
- Update the format and specify dependencies in kernel-parameters.txt.
- Update the help message in Kconfig to reflect that dpm_watchdog_enabled
can be set at runtime as well.
v2: https://lore.kernel.org/all/20260604090756.2884671-3-tzungbi@kernel.org
- Use module parameter and bool for dpm_watchdog_enabled.
- Use IS_ENABLED().
v1: https://lore.kernel.org/all/20260528103215.505795-1-tzungbi@kernel.org
---
Documentation/admin-guide/kernel-parameters.txt | 7 +++++++
drivers/base/power/main.c | 11 +++++++++++
kernel/power/Kconfig | 10 ++++++++++
3 files changed, 28 insertions(+)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b5493a7f8f22..ea0b70f87472 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -47,6 +47,7 @@
PCI PCI bus support is enabled.
PCIE PCI Express support is enabled.
PCMCIA The PCMCIA subsystem is enabled.
+ PM Power Management support is enabled.
PNP Plug & Play support is enabled.
PPC PowerPC architecture is enabled.
PPT Parallel port support is enabled.
@@ -5354,6 +5355,12 @@ Kernel parameters
pm_debug_messages [SUSPEND,KNL]
Enable suspend/resume debug messages during boot up.
+ pm.dpm_watchdog_enabled=
+ [PM] Enable or disable the DPM watchdog. Requires
+ CONFIG_PM_SLEEP and CONFIG_DPM_WATCHDOG enabled.
+ Format: <bool>
+ Default value is set by CONFIG_DPM_WATCHDOG_ENABLED.
+
pnp.debug=1 [PNP]
Enable PNP debug messages (depends on the
CONFIG_PNP_DEBUG_MESSAGES option). Change at run-time
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 49ea6e2cd735..184dc4b3b938 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -535,6 +535,11 @@ module_param(dpm_watchdog_all_cpu_backtrace, bool, 0644);
MODULE_PARM_DESC(dpm_watchdog_all_cpu_backtrace,
"Backtrace all CPUs on DPM watchdog timeout");
+static bool __read_mostly dpm_watchdog_enabled =
+ IS_ENABLED(CONFIG_DPM_WATCHDOG_ENABLED);
+module_param(dpm_watchdog_enabled, bool, 0644);
+MODULE_PARM_DESC(dpm_watchdog_enabled, "Enable DPM watchdog");
+
static unsigned int __read_mostly dpm_watchdog_timeout = CONFIG_DPM_WATCHDOG_TIMEOUT;
static unsigned int __read_mostly dpm_watchdog_warning_timeout =
CONFIG_DPM_WATCHDOG_WARNING_TIMEOUT;
@@ -630,6 +635,9 @@ static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
{
struct timer_list *timer = &wd->timer;
+ if (!dpm_watchdog_enabled)
+ return;
+
wd->dev = dev;
wd->tsk = current;
wd->fatal = dpm_watchdog_timeout == dpm_watchdog_warning_timeout;
@@ -648,6 +656,9 @@ static void dpm_watchdog_clear(struct dpm_watchdog *wd)
{
struct timer_list *timer = &wd->timer;
+ if (!dpm_watchdog_enabled)
+ return;
+
timer_delete_sync(timer);
timer_destroy_on_stack(timer);
}
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 530c897311d4..71165e7f04f4 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -268,6 +268,16 @@ config DPM_WATCHDOG
captured in pstore device for inspection in subsequent
boot session.
+config DPM_WATCHDOG_ENABLED
+ bool "Enable DPM watchdog by default"
+ depends on DPM_WATCHDOG
+ default y
+ help
+ If you say Y here, the DPM watchdog will be enabled by default.
+ If you say N, it will be compiled in but disabled. It can be
+ enabled at boot time via the "pm.dpm_watchdog_enabled" kernel
+ parameter or at runtime via sysfs.
+
config DPM_WATCHDOG_TIMEOUT
int "Watchdog timeout to panic in seconds"
range 1 120
--
2.55.0.795.g602f6c329a-goog
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