From 3b8650f2e8810f0baa48608c8dfe4f44120de123 Mon Sep 17 00:00:00 2001 From: Li Jun Date: Thu, 27 Aug 2026 20:32:56 +0800 Subject: [PATCH 1/2] PM: hibernate: docs: update swsusp.txt references to swsusp.rst The swsusp.txt documentation file has been renamed to swsusp.rst. Update the references in the Documentation/power/userland-swsusp.rst comments to use the correct filename. Signed-off-by: Li Jun [ rjw: Subject adjustment ] Link: https://patch.msgid.link/20260827123256.2548946-1-lijun01@kylinos.cn Signed-off-by: Rafael J. Wysocki --- Documentation/power/userland-swsusp.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/power/userland-swsusp.rst b/Documentation/power/userland-swsusp.rst index 1cf62d80a9ca..b00b850148b2 100644 --- a/Documentation/power/userland-swsusp.rst +++ b/Documentation/power/userland-swsusp.rst @@ -4,9 +4,9 @@ Documentation for userland software suspend interface (C) 2006 Rafael J. Wysocki -First, the warnings at the beginning of swsusp.txt still apply. +First, the warnings at the beginning of swsusp.rst still apply. -Second, you should read the FAQ in swsusp.txt _now_ if you have not +Second, you should read the FAQ in swsusp.rst _now_ if you have not done it already. Now, to use the userland interface for software suspend you need special From 33392343c74e417375b87032c66078a3bbc1dc91 Mon Sep 17 00:00:00 2001 From: Mayank Rungta Date: Wed, 9 Sep 2026 15:48:18 -0700 Subject: [PATCH 2/2] PM: sleep: Add DPM watchdog to prepare/late/early/noirq/complete phases Extend the DPM watchdog to wrap device_prepare, device_suspend_late, device_suspend_noirq, device_resume_noirq, device_resume_early, and device_complete callbacks. If a driver hangs during these transitions, the watchdog will fire and dump a stack trace to help identify the offending driver. To prevent false-positive timeouts, the watchdog is set only after waiting for subordinate (during suspend) and superior (during resume) devices. With this change, DPM watchdog coverage is extended across all phases of system sleep transitions. Signed-off-by: Mayank Rungta Reviewed-by: Douglas Anderson Reviewed-by: Tzung-Bi Shih Link: https://patch.msgid.link/20260909224818.2177311-1-mrungta@google.com Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-) diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index e130da428141..4e0d6357a37c 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -802,6 +802,7 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy const char *info = NULL; bool skip_resume; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); TRACE_DEVICE(dev); TRACE_RESUME(0); @@ -827,6 +828,7 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy if (!dpm_wait_for_superior(dev, async)) goto Out; + dpm_watchdog_set(&wd, dev); skip_resume = dev_pm_skip_resume(dev); /* * If the driver callback is skipped below or by the middle layer @@ -871,6 +873,7 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy error = dpm_run_callback(callback, dev, state, info); Skip: + dpm_watchdog_clear(&wd); dev->power.is_noirq_suspended = false; Out: @@ -971,6 +974,7 @@ static void device_resume_early(struct device *dev, pm_message_t state, bool asy pm_callback_t callback = NULL; const char *info = NULL; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); TRACE_DEVICE(dev); TRACE_RESUME(0); @@ -987,6 +991,7 @@ static void device_resume_early(struct device *dev, pm_message_t state, bool asy if (!dpm_wait_for_superior(dev, async)) goto Out; + dpm_watchdog_set(&wd, dev); if (dev->pm_domain) { info = "early power domain "; callback = pm_late_early_op(&dev->pm_domain->ops, state); @@ -1004,7 +1009,7 @@ static void device_resume_early(struct device *dev, pm_message_t state, bool asy goto Run; if (dev_pm_skip_resume(dev)) - goto Skip; + goto End; if (dev->driver && dev->driver->pm) { info = "early driver "; @@ -1014,6 +1019,9 @@ static void device_resume_early(struct device *dev, pm_message_t state, bool asy Run: error = dpm_run_callback(callback, dev, state, info); +End: + dpm_watchdog_clear(&wd); + Skip: dev->power.is_late_suspended = false; pm_runtime_enable(dev); @@ -1281,10 +1289,12 @@ static void device_complete(struct device *dev, pm_message_t state) { void (*callback)(struct device *) = NULL; const char *info = NULL; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); if (dev->power.syscore) goto out; + dpm_watchdog_set(&wd, dev); device_lock(dev); if (dev->pm_domain) { @@ -1312,6 +1322,7 @@ static void device_complete(struct device *dev, pm_message_t state) } device_unlock(dev); + dpm_watchdog_clear(&wd); out: /* If enabling runtime PM for the device is blocked, unblock it. */ @@ -1508,6 +1519,7 @@ static void device_suspend_noirq(struct device *dev, pm_message_t state, bool as pm_callback_t callback = NULL; const char *info = NULL; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); TRACE_DEVICE(dev); TRACE_SUSPEND(0); @@ -1520,6 +1532,7 @@ static void device_suspend_noirq(struct device *dev, pm_message_t state, bool as if (dev->power.syscore || dev->power.direct_complete) goto Complete; + dpm_watchdog_set(&wd, dev); if (dev->pm_domain) { info = "noirq power domain "; callback = pm_noirq_op(&dev->pm_domain->ops, state); @@ -1550,7 +1563,7 @@ static void device_suspend_noirq(struct device *dev, pm_message_t state, bool as WRITE_ONCE(async_error, error); dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async noirq" : " noirq", error); - goto Complete; + goto End; } Skip: @@ -1569,6 +1582,9 @@ static void device_suspend_noirq(struct device *dev, pm_message_t state, bool as if (dev->power.must_resume) dpm_superior_set_must_resume(dev); +End: + dpm_watchdog_clear(&wd); + Complete: complete_all(&dev->power.completion); TRACE_SUSPEND(error); @@ -1703,6 +1719,7 @@ static void device_suspend_late(struct device *dev, pm_message_t state, bool asy pm_callback_t callback = NULL; const char *info = NULL; int error = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); TRACE_DEVICE(dev); TRACE_SUSPEND(0); @@ -1720,6 +1737,8 @@ static void device_suspend_late(struct device *dev, pm_message_t state, bool asy if (dev->power.direct_complete) goto Complete; + dpm_watchdog_set(&wd, dev); + /* * After this point, any runtime PM operations targeting the device * will fail until the corresponding pm_runtime_enable() call in @@ -1761,13 +1780,16 @@ static void device_suspend_late(struct device *dev, pm_message_t state, bool asy dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, async ? " async late" : " late", error); pm_runtime_enable(dev); - goto Complete; + goto End; } dpm_propagate_wakeup_to_parent(dev); Skip: dev->power.is_late_suspended = true; +End: + dpm_watchdog_clear(&wd); + Complete: TRACE_SUSPEND(error); complete_all(&dev->power.completion); @@ -2201,6 +2223,7 @@ static int device_prepare(struct device *dev, pm_message_t state) int (*callback)(struct device *) = NULL; bool smart_suspend; int ret = 0; + DECLARE_DPM_WATCHDOG_ON_STACK(wd); /* * If a device's parent goes into runtime suspend at the wrong time, @@ -2220,6 +2243,7 @@ static int device_prepare(struct device *dev, pm_message_t state) if (dev->power.syscore) return 0; + dpm_watchdog_set(&wd, dev); device_lock(dev); dev->power.wakeup_path = false; @@ -2245,6 +2269,7 @@ static int device_prepare(struct device *dev, pm_message_t state) unlock: device_unlock(dev); + dpm_watchdog_clear(&wd); if (ret < 0) { suspend_report_result(dev, callback, ret);