kernel/linux.git/drivers/base/power/main.c, branch v6.6.131

PM: sleep: core: Clear power.must_resume in noirq suspend error path

2025-10-15T09:57:51+00:00

[ Upstream commit be82483d1b60baf6747884bd74cb7de484deaf76 ] If system suspend is aborted in the "noirq" phase (for instance, due to an error returned by one of the device callbacks), power.is_noirq_suspended will not be set for some devices and device_resume_noirq() will return early for them. Consequently, noirq resume callbacks will not run for them at all because the noirq suspend callbacks have not run for them yet. If any of them has power.must_resume set and late suspend has been skipped for it (due to power.smart_suspend), early resume should be skipped for it either, or its state may become inconsistent (for instance, if the early resume assumes that it will always follow noirq resume). Make that happen by clearing power.must_resume in device_resume_noirq() for devices with power.is_noirq_suspended clear that have been left in suspend by device_suspend_late(), which will subsequently cause device_resume_early() to leave the device in suspend and avoid changing its state. Fixes: 0d4b54c6fee8 ("PM / core: Add LEAVE_SUSPENDED driver flag") Link: https://lore.kernel.org/linux-pm/5d692b81-6f58-4e86-9cb0-ede69a09d799@rowland.harvard.edu/ Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Link: https://patch.msgid.link/3381776.aeNJFYEL58@rafael.j.wysocki Signed-off-by: Sasha Levin

PM: sleep: Fix power.is_suspended cleanup for direct-complete devices

2025-06-19T13:28:34+00:00

[ Upstream commit d46c4c839c20a599a0eb8d73708ce401f9c7d06d ] Commit 03f1444016b7 ("PM: sleep: Fix handling devices with direct_complete set on errors") caused power.is_suspended to be set for devices with power.direct_complete set, but it forgot to ensure the clearing of that flag for them in device_resume(), so power.is_suspended is still set for them during the next system suspend-resume cycle. If that cycle is aborted in dpm_suspend(), the subsequent invocation of dpm_resume() will trigger a device_resume() call for every device and because power.is_suspended is set for the devices in question, they will not be skipped by device_resume() as expected which causes scary error messages to be logged (as appropriate). To address this issue, move the clearing of power.is_suspended in device_resume() immediately after the power.is_suspended check so it will be always cleared for all devices processed by that function. Fixes: 03f1444016b7 ("PM: sleep: Fix handling devices with direct_complete set on errors") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4280 Reported-and-tested-by: Chris Bainbridge Signed-off-by: Rafael J. Wysocki Reviewed-by: Mario Limonciello Link: https://patch.msgid.link/4990586.GXAFRqVoOG@rjwysocki.net Signed-off-by: Sasha Levin

PM: sleep: Fix handling devices with direct_complete set on errors

2025-04-10T12:37:26+00:00

[ Upstream commit 03f1444016b71feffa1dfb8a51f15ba592f94b13 ] When dpm_suspend() fails, some devices with power.direct_complete set may not have been handled by device_suspend() yet, so runtime PM has not been disabled for them yet even though power.direct_complete is set. Since device_resume() expects that runtime PM has been disabled for all devices with power.direct_complete set, it will attempt to reenable runtime PM for the devices that have not been processed by device_suspend() which does not make sense. Had those devices had runtime PM disabled before device_suspend() had run, device_resume() would have inadvertently enable runtime PM for them, but this is not expected to happen because it would require ->prepare() callbacks to return positive values for devices with runtime PM disabled, which would be invalid. In practice, this issue is most likely benign because pm_runtime_enable() will not allow the "disable depth" counter to underflow, but it causes a warning message to be printed for each affected device. To allow device_resume() to distinguish the "direct complete" devices that have been processed by device_suspend() from those which have not been handled by it, make device_suspend() set power.is_suspended for "direct complete" devices. Next, move the power.is_suspended check in device_resume() before the power.direct_complete check in it to make it skip the "direct complete" devices that have not been handled by device_suspend(). This change is based on a preliminary patch from Saravana Kannan. Fixes: aae4518b3124 ("PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily") Link: https://lore.kernel.org/linux-pm/20241114220921.2529905-2-saravanak@google.com/ Reported-by: Saravana Kannan Signed-off-by: Rafael J. Wysocki Reviewed-by: Saravana Kannan Link: https://patch.msgid.link/12627587.O9o76ZdvQC@rjwysocki.net Signed-off-by: Sasha Levin

PM: sleep: Adjust check before setting power.must_resume

2025-04-10T12:37:26+00:00

[ Upstream commit eeb87d17aceab7803a5a5bcb6cf2817b745157cf ] The check before setting power.must_resume in device_suspend_noirq() does not take power.child_count into account, but it should do that, so use pm_runtime_need_not_resume() in it for this purpose and adjust the comment next to it accordingly. Fixes: 107d47b2b95e ("PM: sleep: core: Simplify the SMART_SUSPEND flag handling") Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Link: https://patch.msgid.link/3353728.44csPzL39Z@rjwysocki.net Signed-off-by: Sasha Levin

PM: sleep: Fix possible deadlocks in core system-wide PM code

2024-02-01T00:18:49+00:00

commit 7839d0078e0d5e6cc2fa0b0dfbee71de74f1e557 upstream. It is reported that in low-memory situations the system-wide resume core code deadlocks, because async_schedule_dev() executes its argument function synchronously if it cannot allocate memory (and not only in that case) and that function attempts to acquire a mutex that is already held. Executing the argument function synchronously from within dpm_async_fn() may also be problematic for ordering reasons (it may cause a consumer device's resume callback to be invoked before a requisite supplier device's one, for example). Address this by changing the code in question to use async_schedule_dev_nocall() for scheduling the asynchronous execution of device suspend and resume functions and to directly run them synchronously if async_schedule_dev_nocall() returns false. Link: https://lore.kernel.org/linux-pm/ZYvjiqX6EsL15moe@perf/ Reported-by: Youngmin Nam Signed-off-by: Rafael J. Wysocki Reviewed-by: Stanislaw Gruszka Tested-by: Youngmin Nam Reviewed-by: Ulf Hansson Cc: 5.7+ # 5.7+: 6aa09a5bccd8 async: Split async_schedule_node_domain() Cc: 5.7+ # 5.7+: 7d4b5d7a37bd async: Introduce async_schedule_dev_nocall() Cc: 5.7+ # 5.7+ Signed-off-by: Greg Kroah-Hartman

PM: core: Remove unnecessary (void *) conversions

2023-04-07T11:27:13+00:00

Assignments from pointer variables of type (void *) do not require explicit type casts, so remove such type cases from the code in drivers/base/power/main.c where applicable. Signed-off-by: Li zeming [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki

Merge branches 'pm-sleep', 'pm-domains' and 'pm-docs'

2022-03-18T17:29:21+00:00

Merge changes related to system sleep, PM domains changes and power management documentation changes for 5.18-rc1: - Fix load_image_and_restore() error path (Ye Bin). - Fix typos in comments in the system wakeup hadling code (Tom Rix). - Clean up non-kernel-doc comments in hibernation code (Jiapeng Chong). - Fix __setup handler error handling in system-wide suspend and hibernation core code (Randy Dunlap). - Add device name to suspend_report_result() (Youngjin Jang). - Make virtual guests honour ACPI S4 hardware signature by default (David Woodhouse). - Block power off of a parent PM domain unless child is in deepest state (Ulf Hansson). - Use dev_err_probe() to simplify error handling for generic PM domains (Ahmad Fatoum). - Fix sleep-in-atomic bug caused by genpd_debug_remove() (Shawn Guo). - Document Intel uncore frequency scaling (Srinivas Pandruvada). * pm-sleep: PM: hibernate: Honour ACPI hardware signature by default for virtual guests PM: sleep: Add device name to suspend_report_result() PM: suspend: fix return value of __setup handler PM: hibernate: fix __setup handler error handling PM: hibernate: Clean up non-kernel-doc comments PM: sleep: wakeup: Fix typos in comments PM: hibernate: fix load_image_and_restore() error path * pm-domains: PM: domains: Fix sleep-in-atomic bug caused by genpd_debug_remove() PM: domains: use dev_err_probe() to simplify error handling PM: domains: Prevent power off for parent unless child is in deepest state * pm-docs: Documentation: admin-guide: pm: Document uncore frequency scaling

PM: core: keep irq flags in device_pm_check_callbacks()

2022-03-10T18:40:15+00:00

The function device_pm_check_callbacks() can be called under the spin lock (in the reported case it happens from genpd_add_device() -> dev_pm_domain_set(), when the genpd uses spinlocks rather than mutexes. However this function uncoditionally uses spin_lock_irq() / spin_unlock_irq(), thus not preserving the CPU flags. Use the irqsave/irqrestore instead. The backtrace for the reference: [ 2.752010] ------------[ cut here ]------------ [ 2.756769] raw_local_irq_restore() called with IRQs enabled [ 2.762596] WARNING: CPU: 4 PID: 1 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x34/0x50 [ 2.772338] Modules linked in: [ 2.775487] CPU: 4 PID: 1 Comm: swapper/0 Tainted: G S 5.17.0-rc6-00384-ge330d0d82eff-dirty #684 [ 2.781384] Freeing initrd memory: 46024K [ 2.785839] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.785841] pc : warn_bogus_irq_restore+0x34/0x50 [ 2.785844] lr : warn_bogus_irq_restore+0x34/0x50 [ 2.785846] sp : ffff80000805b7d0 [ 2.785847] x29: ffff80000805b7d0 x28: 0000000000000000 x27: 0000000000000002 [ 2.785850] x26: ffffd40e80930b18 x25: ffff7ee2329192b8 x24: ffff7edfc9f60800 [ 2.785853] x23: ffffd40e80930b18 x22: ffffd40e80930d30 x21: ffff7edfc0dffa00 [ 2.785856] x20: ffff7edfc09e3768 x19: 0000000000000000 x18: ffffffffffffffff [ 2.845775] x17: 6572206f74206465 x16: 6c696166203a3030 x15: ffff80008805b4f7 [ 2.853108] x14: 0000000000000000 x13: ffffd40e809550b0 x12: 00000000000003d8 [ 2.860441] x11: 0000000000000148 x10: ffffd40e809550b0 x9 : ffffd40e809550b0 [ 2.867774] x8 : 00000000ffffefff x7 : ffffd40e809ad0b0 x6 : ffffd40e809ad0b0 [ 2.875107] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000 [ 2.882440] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff7edfc03a8000 [ 2.889774] Call trace: [ 2.892290] warn_bogus_irq_restore+0x34/0x50 [ 2.896770] _raw_spin_unlock_irqrestore+0x94/0xa0 [ 2.901690] genpd_unlock_spin+0x20/0x30 [ 2.905724] genpd_add_device+0x100/0x2d0 [ 2.909850] __genpd_dev_pm_attach+0xa8/0x23c [ 2.914329] genpd_dev_pm_attach_by_id+0xc4/0x190 [ 2.919167] genpd_dev_pm_attach_by_name+0x3c/0xd0 [ 2.924086] dev_pm_domain_attach_by_name+0x24/0x30 [ 2.929102] psci_dt_attach_cpu+0x24/0x90 [ 2.933230] psci_cpuidle_probe+0x2d4/0x46c [ 2.937534] platform_probe+0x68/0xe0 [ 2.941304] really_probe.part.0+0x9c/0x2fc [ 2.945605] __driver_probe_device+0x98/0x144 [ 2.950085] driver_probe_device+0x44/0x15c [ 2.954385] __device_attach_driver+0xb8/0x120 [ 2.958950] bus_for_each_drv+0x78/0xd0 [ 2.962896] __device_attach+0xd8/0x180 [ 2.966843] device_initial_probe+0x14/0x20 [ 2.971144] bus_probe_device+0x9c/0xa4 [ 2.975092] device_add+0x380/0x88c [ 2.978679] platform_device_add+0x114/0x234 [ 2.983067] platform_device_register_full+0x100/0x190 [ 2.988344] psci_idle_init+0x6c/0xb0 [ 2.992113] do_one_initcall+0x74/0x3a0 [ 2.996060] kernel_init_freeable+0x2fc/0x384 [ 3.000543] kernel_init+0x28/0x130 [ 3.004132] ret_from_fork+0x10/0x20 [ 3.007817] irq event stamp: 319826 [ 3.011404] hardirqs last enabled at (319825): [] __up_console_sem+0x78/0x84 [ 3.020332] hardirqs last disabled at (319826): [] el1_dbg+0x24/0x8c [ 3.028458] softirqs last enabled at (318312): [] _stext+0x410/0x588 [ 3.036678] softirqs last disabled at (318299): [] __irq_exit_rcu+0x158/0x174 [ 3.045607] ---[ end trace 0000000000000000 ]--- Signed-off-by: Dmitry Baryshkov Signed-off-by: Rafael J. Wysocki

PM: sleep: Add device name to suspend_report_result()

2022-03-08T18:57:01+00:00

Currently, suspend_report_result() prints only function information. If any driver uses a common PM function, nobody knows who exactly called the failing function. A device pinter is needed to recognize the failing device. For example: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0 PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0 become after the change: serial 00:05: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0 pci 0000:00:01.3: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0 Signed-off-by: Youngjin Jang [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki

PM: sleep: Fix error handling in dpm_prepare()

2021-12-17T17:36:08+00:00

Commit 2aa36604e824 ("PM: sleep: Avoid calling put_device() under dpm_list_mtx") forgot to update the while () loop termination condition to also break the loop if error is nonzero, which causes the loop to become infinite if device_prepare() returns an error for one device. Add the missing !error check. Fixes: 2aa36604e824 ("PM: sleep: Avoid calling put_device() under dpm_list_mtx") Signed-off-by: Rafael J. Wysocki Reported-by: Thomas Hellström Reviewed-by: Thomas Hellström Reviewed-by: Ulf Hansson Cc: All applicable