From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 60EBB3B0AD7; Wed, 8 Jul 2026 04:34:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783485260; cv=none; b=d4f/51ud89Z92Lqel21Qv5IE33KYWjeIFWWRvQRm1sK8qWJgnOLxgoU69zqEpNMs40Abg41bdnq5lPMiWOsyW9RuvZL5yUoaZU5q2k59EsbgBm2spGOhUmUPwzJxTSgQXetlrhxBo8FdlxRbAk3GMyaM6m7x2GRRpfalkF+9WeI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783485260; c=relaxed/simple; bh=3Qf77x5UNso8Szde6l9Wn6t4nKVUvU94zkIFBCO0Y2E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Ky7mCDpgRedVQRkg9QuoDkhExZ5C7ULHLM0uVR7KfCAOF2LxDyweTMUbSotIzxQ4y5a89N2xbk8N/OxUUgxg/BNcRlxjGU+sbBHE9XgPDI1/zTgx8qe9aOdu+raGiNm013jbj9z+TnQw4T83KGFEo7hW9TJdYdZaW9+ggUROro8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=A/17wdEM; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="A/17wdEM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FFF91F000E9; Wed, 8 Jul 2026 04:34:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783485259; bh=iUtm5SAe2SeQY6Iq7y1PN0eZx12oV8hhEPW1fl/WPVM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=A/17wdEMrVWCVbFD/bxICv6Rj5UU94gKQRI/BgQDjcBjV7McTmdbOTNmC19e1ZaZV UrbG97uyqtom3gA7r/HnpjiTi2w9hN6buqPpn5CPgVXBTDsw/CJPWBfOxj92h0Vu6T H+YaO7ya0cRKN0Ny7Rl7C94OYNYkihGhcfWqrLrlnhGQx8jP+dM5P2yFS0kC0gUq4y o6pXjkxah579iCz84d3/t08bdZohwM8+1Pf/z+6r2EV88dZo2XkQ+OnB8wz1pCn0Cc xuYX7Xs052v20zXzcQlndSvB2mCTCHPraFh46iP1PrsfuOV4w/LmxavJosGNAxhSPZ YJYoalXZ+KCWQ== From: Tzung-Bi Shih To: Jonathan Corbet , "Rafael J. Wysocki" , Greg Kroah-Hartman , Danilo Krummrich Cc: Shuah Khan , Pavel Machek , Len Brown , tzungbi@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, driver-core@lists.linux.dev, tfiga@chromium.org, senozhatsky@chromium.org, Randy Dunlap Subject: [PATCH v6 2/2] PM: dpm_watchdog: Allow disabling DPM watchdog by default Date: Wed, 8 Jul 2026 04:33:17 +0000 Message-ID: <20260708043317.2980098-3-tzungbi@kernel.org> X-Mailer: git-send-email 2.55.0.795.g602f6c329a-goog In-Reply-To: <20260708043317.2980098-1-tzungbi@kernel.org> References: <20260708043317.2980098-1-tzungbi@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- 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: + 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