kernel/linux.git/drivers/base/power, branch v5.4.239

PM: runtime: Do not call __rpm_callback() from rpm_idle()

2023-01-18T10:40:57+00:00

[ Upstream commit bc80c2e438dcbfcf748452ec0f7ad5b79ff3ad88 ] Calling __rpm_callback() from rpm_idle() after adding device links support to the former is a clear mistake. Not only it causes rpm_idle() to carry out unnecessary actions, but it is also against the assumption regarding the stability of PM-runtime status across __rpm_callback() invocations, because rpm_suspend() and rpm_resume() may run in parallel with __rpm_callback() when it is called by rpm_idle() and the device's PM-runtime status can be updated by any of them. Fixes: 21d5c57b3726 ("PM / runtime: Use device links") Link: https://lore.kernel.org/linux-pm/36aed941-a73e-d937-2721-4f0decd61ce0@quicinc.com Signed-off-by: Rafael J. Wysocki Reviewed-by: Adrian Hunter Signed-off-by: Sasha Levin

PM: runtime: Improve path in rpm_idle() when no callback

2023-01-18T10:40:57+00:00

[ Upstream commit 5a2bd1b1c64e1ac5627db3767ac465f18606315c ] When pm_runtime_no_callbacks() has been called for a struct device to set the dev->power.no_callbacks flag for it, it enables rpm_idle() to take a slightly quicker path by assuming that a ->runtime_idle() callback would have returned 0 to indicate success. A device that does not have the dev->power.no_callbacks flag set for it, may still be missing a corresponding ->runtime_idle() callback, in which case the slower path in rpm_idle() is taken. Let's improve the behaviour for this case, by aligning code to the quicker path. Signed-off-by: Ulf Hansson Acked-by: Alan Stern Signed-off-by: Rafael J. Wysocki Stable-dep-of: bc80c2e438dc ("PM: runtime: Do not call __rpm_callback() from rpm_idle()") Signed-off-by: Sasha Levin

PM: domains: Fix handling of unavailable/disabled idle states

2022-11-03T14:56:56+00:00

[ Upstream commit e0c57a5c70c13317238cb19a7ded0eab4a5f7de5 ] Platforms can provide the information about the availability of each idle states via status flag. Platforms may have to disable one or more idle states for various reasons like broken firmware or other unmet dependencies. Fix handling of such unavailable/disabled idle states by ignoring them while parsing the states. Fixes: a3381e3a65cb ("PM / domains: Fix up domain-idle-states OF parsing") Signed-off-by: Sudeep Holla Reviewed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

PM: core: keep irq flags in device_pm_check_callbacks()

2022-04-15T12:18:23+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: s2idle: ACPI: Fix wakeup interrupts handling

2022-02-16T11:52:50+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

drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions

2022-01-16T08:15:38+00:00

commit aa838896d87af561a33ecefea1caa4c15a68bc47 upstream. Convert the various sprintf fmaily calls in sysfs device show functions to sysfs_emit and sysfs_emit_at for PAGE_SIZE buffer safety. Done with: $ spatch -sp-file sysfs_emit_dev.cocci --in-place --max-width=80 . And cocci script: $ cat sysfs_emit_dev.cocci @@ identifier d_show; identifier dev, attr, buf; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... return - sprintf(buf, + sysfs_emit(buf, ...); ...> } @@ identifier d_show; identifier dev, attr, buf; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... return - snprintf(buf, PAGE_SIZE, + sysfs_emit(buf, ...); ...> } @@ identifier d_show; identifier dev, attr, buf; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... return - scnprintf(buf, PAGE_SIZE, + sysfs_emit(buf, ...); ...> } @@ identifier d_show; identifier dev, attr, buf; expression chr; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... return - strcpy(buf, chr); + sysfs_emit(buf, chr); ...> } @@ identifier d_show; identifier dev, attr, buf; identifier len; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... len = - sprintf(buf, + sysfs_emit(buf, ...); ...> return len; } @@ identifier d_show; identifier dev, attr, buf; identifier len; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... len = - snprintf(buf, PAGE_SIZE, + sysfs_emit(buf, ...); ...> return len; } @@ identifier d_show; identifier dev, attr, buf; identifier len; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... len = - scnprintf(buf, PAGE_SIZE, + sysfs_emit(buf, ...); ...> return len; } @@ identifier d_show; identifier dev, attr, buf; identifier len; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { <... - len += scnprintf(buf + len, PAGE_SIZE - len, + len += sysfs_emit_at(buf, len, ...); ...> return len; } @@ identifier d_show; identifier dev, attr, buf; expression chr; @@ ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf) { ... - strcpy(buf, chr); - return strlen(buf); + return sysfs_emit(buf, chr); } Signed-off-by: Joe Perches Link: https://lore.kernel.org/r/3d033c33056d88bbe34d4ddb62afd05ee166ab9a.1600285923.git.joe@perches.com Cc: Lee Jones Signed-off-by: Greg Kroah-Hartman

PM: base: power: don't try to use non-existing RTC for storing data

2021-09-22T10:26:39+00:00

commit 0560204b360a332c321124dbc5cdfd3364533a74 upstream. If there is no legacy RTC device, don't try to use it for storing trace data across suspend/resume. Cc: Signed-off-by: Juergen Gross Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20210903084937.19392-2-jgross@suse.com Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman

PM: runtime: Fix unpaired parent child_count for force_resume

2021-05-19T08:08:20+00:00

commit c745253e2a691a40c66790defe85c104a887e14a upstream. As pm_runtime_need_not_resume() relies also on usage_count, it can return a different value in pm_runtime_force_suspend() compared to when called in pm_runtime_force_resume(). Different return values can happen if anything calls PM runtime functions in between, and causes the parent child_count to increase on every resume. So far I've seen the issue only for omapdrm that does complicated things with PM runtime calls during system suspend for legacy reasons: omap_atomic_commit_tail() for omapdrm.0 dispc_runtime_get() wakes up 58000000.dss as it's the dispc parent dispc_runtime_resume() rpm_resume() increases parent child_count dispc_runtime_put() won't idle, PM runtime suspend blocked pm_runtime_force_suspend() for 58000000.dss, !pm_runtime_need_not_resume() __update_runtime_status() system suspended pm_runtime_force_resume() for 58000000.dss, pm_runtime_need_not_resume() pm_runtime_enable() only called because of pm_runtime_need_not_resume() omap_atomic_commit_tail() for omapdrm.0 dispc_runtime_get() wakes up 58000000.dss as it's the dispc parent dispc_runtime_resume() rpm_resume() increases parent child_count dispc_runtime_put() won't idle, PM runtime suspend blocked ... rpm_suspend for 58000000.dss but parent child_count is now unbalanced Let's fix the issue by adding a flag for needs_force_resume and use it in pm_runtime_force_resume() instead of pm_runtime_need_not_resume(). Additionally omapdrm system suspend could be simplified later on to avoid lots of unnecessary PM runtime calls and the complexity it adds. The driver can just use internal functions that are shared between the PM runtime and system suspend related functions. Fixes: 4918e1f87c5f ("PM / runtime: Rework pm_runtime_force_suspend/resume()") Signed-off-by: Tony Lindgren Reviewed-by: Ulf Hansson Tested-by: Tomi Valkeinen Cc: 4.16+ # 4.16+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM: runtime: Fix ordering in pm_runtime_get_suppliers()

2021-04-07T12:47:42+00:00

commit c0c33442f7203704aef345647e14c2fb86071001 upstream. rpm_active indicates how many times the supplier usage_count has been incremented. Consequently it must be updated after pm_runtime_get_sync() of the supplier, not before. Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Signed-off-by: Adrian Hunter Cc: 5.1+ # 5.1+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM: runtime: Fix race getting/putting suppliers at probe

2021-04-07T12:47:42+00:00

commit 9dfacc54a8661bc8be6e08cffee59596ec59f263 upstream. pm_runtime_put_suppliers() must not decrement rpm_active unless the consumer is suspended. That is because, otherwise, it could suspend suppliers for an active consumer. That can happen as follows: static int driver_probe_device(struct device_driver *drv, struct device *dev) { int ret = 0; if (!device_is_registered(dev)) return -ENODEV; dev->can_match = true; pr_debug("bus: '%s': %s: matched device %s with driver %s\n", drv->bus->name, __func__, dev_name(dev), drv->name); pm_runtime_get_suppliers(dev); if (dev->parent) pm_runtime_get_sync(dev->parent); At this point, dev can runtime suspend so rpm_put_suppliers() can run, rpm_active becomes 1 (the lowest value). pm_runtime_barrier(dev); if (initcall_debug) ret = really_probe_debug(dev, drv); else ret = really_probe(dev, drv); Probe callback can have runtime resumed dev, and then runtime put so dev is awaiting autosuspend, but rpm_active is 2. pm_request_idle(dev); if (dev->parent) pm_runtime_put(dev->parent); pm_runtime_put_suppliers(dev); Now pm_runtime_put_suppliers() will put the supplier i.e. rpm_active 2 -> 1, but consumer can still be active. return ret; } Fix by checking the runtime status. For any status other than RPM_SUSPENDED, rpm_active can be considered to be "owned" by rpm_[get/put]_suppliers() and pm_runtime_put_suppliers() need do nothing. Reported-by: Asutosh Das Fixes: 4c06c4e6cf63 ("driver core: Fix possible supplier PM-usage counter imbalance") Signed-off-by: Adrian Hunter Cc: 5.1+ # 5.1+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman