From e20a70c572539a486dbd91b225fa6a194a5e2122 Mon Sep 17 00:00:00 2001 From: Wentao Liang Date: Sun, 19 Jan 2025 22:32:05 +0800 Subject: [PATCH 1/3] PM: hibernate: Add error handling for syscore_suspend() In hibernation_platform_enter(), the code did not check the return value of syscore_suspend(), potentially leading to a situation where syscore_resume() would be called even if syscore_suspend() failed. This could cause unpredictable behavior or system instability. Modify the code sequence in question to properly handle errors returned by syscore_suspend(). If an error occurs in the suspend path, the code now jumps to label 'Enable_irqs' skipping the syscore_resume() call and only enabling interrupts after setting the system state to SYSTEM_RUNNING. Fixes: 40dc166cb5dd ("PM / Core: Introduce struct syscore_ops for core subsystems PM") Signed-off-by: Wentao Liang Link: https://patch.msgid.link/20250119143205.2103-1-vulab@iscas.ac.cn [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 1f87aa01ba44..10a01af63a80 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -608,7 +608,11 @@ int hibernation_platform_enter(void) local_irq_disable(); system_state = SYSTEM_SUSPEND; - syscore_suspend(); + + error = syscore_suspend(); + if (error) + goto Enable_irqs; + if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; @@ -620,6 +624,7 @@ int hibernation_platform_enter(void) Power_up: syscore_resume(); + Enable_irqs: system_state = SYSTEM_RUNNING; local_irq_enable(); From 4891cd3eba62ac611a7929948cf5588a1abed909 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 16 Jan 2025 17:43:29 +0200 Subject: [PATCH 2/3] PM: Revert "Add EXPORT macros for exporting PM functions" Revert commit 41a337b40e98 ("Add EXPORT macros for exporting PM functions") because the macros added by it are still unused almost two years after they had been introduced. Reported-by: Adrian Hunter Signed-off-by: Andy Shevchenko Link: https://patch.msgid.link/20250116154354.149297-1-andriy.shevchenko@linux.intel.com [ rjw: New changelog ] Signed-off-by: Rafael J. Wysocki --- include/linux/pm.h | 4 ---- 1 file changed, 4 deletions(-) diff --git a/include/linux/pm.h b/include/linux/pm.h index e7f0260f15ad..0627a795892b 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -384,12 +384,8 @@ const struct dev_pm_ops name = { \ #ifdef CONFIG_PM #define _EXPORT_DEV_PM_OPS(name, license, ns) _EXPORT_PM_OPS(name, license, ns) -#define EXPORT_PM_FN_GPL(name) EXPORT_SYMBOL_GPL(name) -#define EXPORT_PM_FN_NS_GPL(name, ns) EXPORT_SYMBOL_NS_GPL(name, "ns") #else #define _EXPORT_DEV_PM_OPS(name, license, ns) _DISCARD_PM_OPS(name, license, ns) -#define EXPORT_PM_FN_GPL(name) -#define EXPORT_PM_FN_NS_GPL(name, ns) #endif #ifdef CONFIG_PM_SLEEP From 3775fc538f535a7c5adaf11990c7932a0bd1f9eb Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 28 Jan 2025 20:24:41 +0100 Subject: [PATCH 3/3] PM: sleep: core: Synchronize runtime PM status of parents and children Commit 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase") overlooked the case in which the parent of a device with DPM_FLAG_SMART_SUSPEND set did not use that flag and could be runtime- suspended before a transition into a system-wide sleep state. In that case, if the child is resumed during the subsequent transition from that state into the working state, its runtime PM status will be set to RPM_ACTIVE, but the runtime PM status of the parent will not be updated accordingly, even though the parent will be resumed too, because of the dev_pm_skip_suspend() check in device_resume_noirq(). Address this problem by tracking the need to set the runtime PM status to RPM_ACTIVE during system-wide resume transitions for devices with DPM_FLAG_SMART_SUSPEND set and all of the devices depended on by them. Fixes: 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase") Closes: https://lore.kernel.org/linux-pm/Z30p2Etwf3F2AUvD@hovoldconsulting.com/ Reported-by: Johan Hovold Tested-by: Manivannan Sadhasivam Signed-off-by: Rafael J. Wysocki Reviewed-by: Johan Hovold Tested-by: Johan Hovold Link: https://patch.msgid.link/12619233.O9o76ZdvQC@rjwysocki.net --- drivers/base/power/main.c | 29 ++++++++++++++++++++--------- include/linux/pm.h | 1 + 2 files changed, 21 insertions(+), 9 deletions(-) diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index cbc9a7a75def..d497d448e4b2 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -656,13 +656,15 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy * so change its status accordingly. * * Otherwise, the device is going to be resumed, so set its PM-runtime - * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set - * to avoid confusing drivers that don't use it. + * status to "active" unless its power.set_active flag is clear, in + * which case it is not necessary to update its PM-runtime status. */ - if (skip_resume) + if (skip_resume) { pm_runtime_set_suspended(dev); - else if (dev_pm_skip_suspend(dev)) + } else if (dev->power.set_active) { pm_runtime_set_active(dev); + dev->power.set_active = false; + } if (dev->pm_domain) { info = "noirq power domain "; @@ -1189,18 +1191,24 @@ static pm_message_t resume_event(pm_message_t sleep_state) return PMSG_ON; } -static void dpm_superior_set_must_resume(struct device *dev) +static void dpm_superior_set_must_resume(struct device *dev, bool set_active) { struct device_link *link; int idx; - if (dev->parent) + if (dev->parent) { dev->parent->power.must_resume = true; + if (set_active) + dev->parent->power.set_active = true; + } idx = device_links_read_lock(); - list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) { link->supplier->power.must_resume = true; + if (set_active) + link->supplier->power.set_active = true; + } device_links_read_unlock(idx); } @@ -1278,8 +1286,11 @@ Skip: dev->power.may_skip_resume)) dev->power.must_resume = true; - if (dev->power.must_resume) - dpm_superior_set_must_resume(dev); + if (dev->power.must_resume) { + dev->power.set_active = dev->power.set_active || + dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND); + dpm_superior_set_must_resume(dev, dev->power.set_active); + } Complete: complete_all(&dev->power.completion); diff --git a/include/linux/pm.h b/include/linux/pm.h index 0627a795892b..0d2597a76dfc 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -679,6 +679,7 @@ struct dev_pm_info { bool no_pm_callbacks:1; /* Owned by the PM core */ bool async_in_progress:1; /* Owned by the PM core */ bool must_resume:1; /* Owned by the PM core */ + bool set_active:1; /* Owned by the PM core */ bool may_skip_resume:1; /* Set by subsystems */ #else bool should_wakeup:1;