kernel/git/stable/linux.git/drivers/base/power, branch linux-5.16.y

rtc: Check return value from mc146818_get_time()

2022-04-13T18:03:12+00:00

[ Upstream commit 0dd8d6cb9eddfe637bcd821bbfd40ebd5a0737b9 ] There are 4 users of mc146818_get_time() and none of them was checking the return value from this function. Change this. Print the appropriate warnings in callers of mc146818_get_time() instead of in the function mc146818_get_time() itself, in order not to add strings to rtc-mc146818-lib.c, which is kind of a library. The callers of alpha_rtc_read_time() and cmos_read_time() may use the contents of (struct rtc_time *) even when the functions return a failure code. Therefore, set the contents of (struct rtc_time *) to 0x00, which looks more sensible then 0xff and aligns with the (possibly stale?) comment in cmos_read_time: /* * If pm_trace abused the RTC for storage, set the timespec to 0, * which tells the caller that this RTC value is unusable. */ For consistency, do this in mc146818_get_time(). Note: hpet_rtc_interrupt() may call mc146818_get_time() many times a second. It is very unlikely, though, that the RTC suddenly stops working and mc146818_get_time() would consistently fail. Only compile-tested on alpha. Signed-off-by: Mateusz Jończyk Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: Dave Hansen Cc: Alessandro Zummo Cc: Alexandre Belloni Cc: linux-alpha@vger.kernel.org Cc: x86@kernel.org Signed-off-by: Alexandre Belloni Link: https://lore.kernel.org/r/20211210200131.153887-4-mat.jonczyk@o2.pl Signed-off-by: Sasha Levin

PM: core: keep irq flags in device_pm_check_callbacks()

2022-04-08T12:06:34+00:00

[ Upstream commit 524bb1da785a7ae43dd413cd392b5071c6c367f8 ] 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 Signed-off-by: Sasha Levin

PM: domains: Fix sleep-in-atomic bug caused by genpd_debug_remove()

2022-04-08T12:05:33+00:00

commit f6bfe8b5b2c2a5ac8bd2fc7bca3706e6c3fc26d8 upstream. When a genpd with GENPD_FLAG_IRQ_SAFE gets removed, the following sleep-in-atomic bug will be seen, as genpd_debug_remove() will be called with a spinlock being held. [ 0.029183] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1460 [ 0.029204] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 1, name: swapper/0 [ 0.029219] preempt_count: 1, expected: 0 [ 0.029230] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.17.0-rc4+ #489 [ 0.029245] Hardware name: Thundercomm TurboX CM2290 (DT) [ 0.029256] Call trace: [ 0.029265] dump_backtrace.part.0+0xbc/0xd0 [ 0.029285] show_stack+0x3c/0xa0 [ 0.029298] dump_stack_lvl+0x7c/0xa0 [ 0.029311] dump_stack+0x18/0x34 [ 0.029323] __might_resched+0x10c/0x13c [ 0.029338] __might_sleep+0x4c/0x80 [ 0.029351] down_read+0x24/0xd0 [ 0.029363] lookup_one_len_unlocked+0x9c/0xcc [ 0.029379] lookup_positive_unlocked+0x10/0x50 [ 0.029392] debugfs_lookup+0x68/0xac [ 0.029406] genpd_remove.part.0+0x12c/0x1b4 [ 0.029419] of_genpd_remove_last+0xa8/0xd4 [ 0.029434] psci_cpuidle_domain_probe+0x174/0x53c [ 0.029449] platform_probe+0x68/0xe0 [ 0.029462] really_probe+0x190/0x430 [ 0.029473] __driver_probe_device+0x90/0x18c [ 0.029485] driver_probe_device+0x40/0xe0 [ 0.029497] __driver_attach+0xf4/0x1d0 [ 0.029508] bus_for_each_dev+0x70/0xd0 [ 0.029523] driver_attach+0x24/0x30 [ 0.029534] bus_add_driver+0x164/0x22c [ 0.029545] driver_register+0x78/0x130 [ 0.029556] __platform_driver_register+0x28/0x34 [ 0.029569] psci_idle_init_domains+0x1c/0x28 [ 0.029583] do_one_initcall+0x50/0x1b0 [ 0.029595] kernel_init_freeable+0x214/0x280 [ 0.029609] kernel_init+0x2c/0x13c [ 0.029622] ret_from_fork+0x10/0x20 It doesn't seem necessary to call genpd_debug_remove() with the lock, so move it out from locking to fix the problem. Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains") Signed-off-by: Shawn Guo Reviewed-by: Ulf Hansson Cc: 5.11+ # 5.11+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM: s2idle: ACPI: Fix wakeup interrupts handling

2022-02-16T11:58:24+00:00

commit cb1f65c1e1424a4b5e4a86da8aa3b8fd8459c8ec upstream. After commit e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE") wakeup interrupts occurring immediately after the one discarded by acpi_s2idle_wake() may be missed. Moreover, if the SCI triggers again immediately after the rearming in acpi_s2idle_wake(), that wakeup may be missed too. The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup() when pm_wakeup_irq is 0, but that's not the case any more after the interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is cleared by the pm_wakeup_clear() call in s2idle_loop(). However, there may be wakeup interrupts occurring in that time frame and if that happens, they will be missed. To address that issue first move the clearing of pm_wakeup_irq to the point at which it is known that the interrupt causing acpi_s2idle_wake() to tun will be discarded, before rearming the SCI for wakeup. Moreover, because that only reduces the size of the time window in which the issue may manifest itself, allow pm_system_irq_wakeup() to register two second wakeup interrupts in a row and, when discarding the first one, replace it with the second one. [Of course, this assumes that only one wakeup interrupt can be discarded in one go, but currently that is the case and I am not aware of any plans to change that.] Fixes: e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE") Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM: runtime: Add safety net to supplier device release

2022-01-27T11:02:25+00:00

[ Upstream commit d1579e61192e0e686faa4208500ef4c3b529b16c ] Because refcount_dec_not_one() returns true if the target refcount becomes saturated, it is generally unsafe to use its return value as a loop termination condition, but that is what happens when a device link's supplier device is released during runtime PM suspend operations and on device link removal. To address this, introduce pm_runtime_release_supplier() to be used in the above cases which will check the supplier device's runtime PM usage counter in addition to the refcount_dec_not_one() return value, so the loop can be terminated in case the rpm_active refcount value becomes invalid, and update the code in question to use it as appropriate. This change is not expected to have any visible functional impact. Reported-by: Peter Zijlstra Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Acked-by: Peter Zijlstra (Intel) Signed-off-by: Sasha Levin

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

PM: sleep: Avoid calling put_device() under dpm_list_mtx

2021-11-05T15:10:11+00:00

It is generally unsafe to call put_device() with dpm_list_mtx held, because the given device's release routine may carry out an action depending on that lock which then may deadlock, so modify the system-wide suspend and resume of devices to always drop dpm_list_mtx before calling put_device() (and adjust white space somewhat while at it). For instance, this prevents the following splat from showing up in the kernel log after a system resume in certain configurations: [ 3290.969514] ====================================================== [ 3290.969517] WARNING: possible circular locking dependency detected [ 3290.969519] 5.15.0+ #2420 Tainted: G S [ 3290.969523] ------------------------------------------------------ [ 3290.969525] systemd-sleep/4553 is trying to acquire lock: [ 3290.969529] ffff888117ab1138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: flush_workqueue+0x87/0x4a0 [ 3290.969554] but task is already holding lock: [ 3290.969556] ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0 [ 3290.969571] which lock already depends on the new lock. [ 3290.969573] the existing dependency chain (in reverse order) is: [ 3290.969575] -> #3 (dpm_list_mtx){+.+.}-{3:3}: [ 3290.969583] __mutex_lock+0x9d/0xa30 [ 3290.969591] device_pm_add+0x2e/0xe0 [ 3290.969597] device_add+0x4d5/0x8f0 [ 3290.969605] hci_conn_add_sysfs+0x43/0xb0 [bluetooth] [ 3290.969689] hci_conn_complete_evt.isra.71+0x124/0x750 [bluetooth] [ 3290.969747] hci_event_packet+0xd6c/0x28a0 [bluetooth] [ 3290.969798] hci_rx_work+0x213/0x640 [bluetooth] [ 3290.969842] process_one_work+0x2aa/0x650 [ 3290.969851] worker_thread+0x39/0x400 [ 3290.969859] kthread+0x142/0x170 [ 3290.969865] ret_from_fork+0x22/0x30 [ 3290.969872] -> #2 (&hdev->lock){+.+.}-{3:3}: [ 3290.969881] __mutex_lock+0x9d/0xa30 [ 3290.969887] hci_event_packet+0xba/0x28a0 [bluetooth] [ 3290.969935] hci_rx_work+0x213/0x640 [bluetooth] [ 3290.969978] process_one_work+0x2aa/0x650 [ 3290.969985] worker_thread+0x39/0x400 [ 3290.969993] kthread+0x142/0x170 [ 3290.969999] ret_from_fork+0x22/0x30 [ 3290.970004] -> #1 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}: [ 3290.970013] process_one_work+0x27d/0x650 [ 3290.970020] worker_thread+0x39/0x400 [ 3290.970028] kthread+0x142/0x170 [ 3290.970033] ret_from_fork+0x22/0x30 [ 3290.970038] -> #0 ((wq_completion)hci0#2){+.+.}-{0:0}: [ 3290.970047] __lock_acquire+0x15cb/0x1b50 [ 3290.970054] lock_acquire+0x26c/0x300 [ 3290.970059] flush_workqueue+0xae/0x4a0 [ 3290.970066] drain_workqueue+0xa1/0x130 [ 3290.970073] destroy_workqueue+0x34/0x1f0 [ 3290.970081] hci_release_dev+0x49/0x180 [bluetooth] [ 3290.970130] bt_host_release+0x1d/0x30 [bluetooth] [ 3290.970195] device_release+0x33/0x90 [ 3290.970201] kobject_release+0x63/0x160 [ 3290.970211] dpm_resume+0x164/0x3e0 [ 3290.970215] dpm_resume_end+0xd/0x20 [ 3290.970220] suspend_devices_and_enter+0x1a4/0xba0 [ 3290.970229] pm_suspend+0x26b/0x310 [ 3290.970236] state_store+0x42/0x90 [ 3290.970243] kernfs_fop_write_iter+0x135/0x1b0 [ 3290.970251] new_sync_write+0x125/0x1c0 [ 3290.970257] vfs_write+0x360/0x3c0 [ 3290.970263] ksys_write+0xa7/0xe0 [ 3290.970269] do_syscall_64+0x3a/0x80 [ 3290.970276] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 3290.970284] other info that might help us debug this: [ 3290.970285] Chain exists of: (wq_completion)hci0#2 --> &hdev->lock --> dpm_list_mtx [ 3290.970297] Possible unsafe locking scenario: [ 3290.970299] CPU0 CPU1 [ 3290.970300] ---- ---- [ 3290.970302] lock(dpm_list_mtx); [ 3290.970306] lock(&hdev->lock); [ 3290.970310] lock(dpm_list_mtx); [ 3290.970314] lock((wq_completion)hci0#2); [ 3290.970319] *** DEADLOCK *** [ 3290.970321] 7 locks held by systemd-sleep/4553: [ 3290.970325] #0: ffff888103bcd448 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xa7/0xe0 [ 3290.970341] #1: ffff888115a14488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x103/0x1b0 [ 3290.970355] #2: ffff888100f719e0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x10c/0x1b0 [ 3290.970369] #3: ffffffff82661048 (autosleep_lock){+.+.}-{3:3}, at: state_store+0x12/0x90 [ 3290.970384] #4: ffffffff82658ac8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x9f/0x310 [ 3290.970399] #5: ffffffff827f2a48 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x4c/0x80 [ 3290.970416] #6: ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0 [ 3290.970428] stack backtrace: [ 3290.970431] CPU: 3 PID: 4553 Comm: systemd-sleep Tainted: G S 5.15.0+ #2420 [ 3290.970438] Hardware name: Dell Inc. XPS 13 9380/0RYJWW, BIOS 1.5.0 06/03/2019 [ 3290.970441] Call Trace: [ 3290.970446] dump_stack_lvl+0x44/0x57 [ 3290.970454] check_noncircular+0x105/0x120 [ 3290.970468] ? __lock_acquire+0x15cb/0x1b50 [ 3290.970474] __lock_acquire+0x15cb/0x1b50 [ 3290.970487] lock_acquire+0x26c/0x300 [ 3290.970493] ? flush_workqueue+0x87/0x4a0 [ 3290.970503] ? __raw_spin_lock_init+0x3b/0x60 [ 3290.970510] ? lockdep_init_map_type+0x58/0x240 [ 3290.970519] flush_workqueue+0xae/0x4a0 [ 3290.970526] ? flush_workqueue+0x87/0x4a0 [ 3290.970544] ? drain_workqueue+0xa1/0x130 [ 3290.970552] drain_workqueue+0xa1/0x130 [ 3290.970561] destroy_workqueue+0x34/0x1f0 [ 3290.970572] hci_release_dev+0x49/0x180 [bluetooth] [ 3290.970624] bt_host_release+0x1d/0x30 [bluetooth] [ 3290.970687] device_release+0x33/0x90 [ 3290.970695] kobject_release+0x63/0x160 [ 3290.970705] dpm_resume+0x164/0x3e0 [ 3290.970710] ? dpm_resume_early+0x251/0x3b0 [ 3290.970718] dpm_resume_end+0xd/0x20 [ 3290.970723] suspend_devices_and_enter+0x1a4/0xba0 [ 3290.970737] pm_suspend+0x26b/0x310 [ 3290.970746] state_store+0x42/0x90 [ 3290.970755] kernfs_fop_write_iter+0x135/0x1b0 [ 3290.970764] new_sync_write+0x125/0x1c0 [ 3290.970777] vfs_write+0x360/0x3c0 [ 3290.970785] ksys_write+0xa7/0xe0 [ 3290.970794] do_syscall_64+0x3a/0x80 [ 3290.970803] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 3290.970811] RIP: 0033:0x7f41b1328164 [ 3290.970819] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 4a d2 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83 [ 3290.970824] RSP: 002b:00007ffe6ae21b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 3290.970831] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f41b1328164 [ 3290.970836] RDX: 0000000000000004 RSI: 000055965e651070 RDI: 0000000000000004 [ 3290.970839] RBP: 000055965e651070 R08: 000055965e64f390 R09: 00007f41b1e3d1c0 [ 3290.970843] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000004 [ 3290.970846] R13: 0000000000000001 R14: 000055965e64f2b0 R15: 0000000000000004 Cc: All applicable Signed-off-by: Rafael J. Wysocki

PM: sleep: Fix runtime PM based cpuidle support

2021-11-04T18:45:38+00:00

In the cpuidle-psci case, runtime PM in combination with the generic PM domain (genpd), may be used when entering/exiting a shared idlestate. More precisely, genpd relies on runtime PM to be enabled for the attached device (in this case it belongs to a CPU), to properly manage the reference counting of its PM domain. This works fine most of the time, but during system suspend in dpm_suspend_late(), the PM core disables runtime PM for all devices. Beyond this point, calls to pm_runtime_get_sync() to runtime resume a device may fail and therefore it could also mess up the reference counting in genpd. To fix this problem, let's call wake_up_all_idle_cpus() in dpm_suspend_late(), prior to disabling runtime PM. In this way a device that belongs to a CPU, becomes runtime resumed through cpuidle-psci and stays like that, because the runtime PM usage count has been bumped in device_prepare(). Diagnosed-by: Maulik Shah Suggested-by: Rafael J. Wysocki Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-sleep'

2021-11-02T18:11:49+00:00

Merge updates related to system sleep for 5.16-rc1: - Clean up hib_wait_io() (Falla Coulibaly). - Fix sparse warnings in hibernation-related code (Anders Roxell). - Use vzalloc() and kzalloc() instead of their open-coded equivalents in hibernation-related code (Cai Huoqing). - Prevent user space from crashing the kernel by attempting to restore the system state from a swap partition in use (Ye Bin). - Do not let "syscore" devices runtime-suspend during system PM transitions (Rafael Wysocki). - Do not pause cpuidle in the suspend-to-idle path (Rafael Wysocki). - Pause cpuidle later and resume it earlier during system PM transitions (Rafael Wysocki). - Make system suspend code use valid_state() consistently (Rafael Wysocki). - Add support for enabling wakeup IRQs after invoking the ->runtime_suspend() callback and make two drivers use it (Chunfeng Yun). * pm-sleep: usb: mtu3: enable wake-up interrupt after runtime_suspend called usb: xhci-mtk: enable wake-up interrupt after runtime_suspend called PM / wakeirq: support enabling wake-up irq after runtime_suspend called PM: suspend: Use valid_state() consistently PM: sleep: Pause cpuidle later and resume it earlier during system transitions PM: suspend: Do not pause cpuidle in the suspend-to-idle path PM: sleep: Do not let "syscore" devices runtime-suspend during system transitions PM: hibernate: Get block device exclusively in swsusp_check() PM: hibernate: swap: Use vzalloc() and kzalloc() PM: hibernate: fix sparse warnings Revert "PM: sleep: Do not assume that "mem" is always present" PM: hibernate: Remove blk_status_to_errno in hib_wait_io PM: sleep: Do not assume that "mem" is always present

PM / wakeirq: support enabling wake-up irq after runtime_suspend called

2021-10-27T18:49:32+00:00

When the dedicated wake IRQ is level trigger, and it uses the device's low-power status as the wakeup source, that means if the device is not in low-power state, the wake IRQ will be triggered if enabled; For this case, need enable the wake IRQ after running the device's ->runtime_suspend() which make it enter low-power state. e.g. Assume the wake IRQ is a low level trigger type, and the wakeup signal comes from the low-power status of the device. The wakeup signal is low level at running time (0), and becomes high level when the device enters low-power state (runtime_suspend (1) is called), a wakeup event at (2) make the device exit low-power state, then the wakeup signal also becomes low level. ------------------ | ^ ^| ---------------- | | -------------- |<---(0)--->|<--(1)--| (3) (2) (4) if enable the wake IRQ before running runtime_suspend during (0), a wake IRQ will arise, it causes resume immediately; it works if enable wake IRQ ( e.g. at (3) or (4)) after running ->runtime_suspend(). This patch introduces a new status WAKE_IRQ_DEDICATED_REVERSE to optionally support enabling wake IRQ after running ->runtime_suspend(). Suggested-by: Rafael J. Wysocki Signed-off-by: Chunfeng Yun Signed-off-by: Rafael J. Wysocki