From 183edb20e60a73925bf3b60e2f4796898167262f Mon Sep 17 00:00:00 2001 From: Yangtao Li Date: Mon, 3 Feb 2020 15:45:17 +0000 Subject: [PATCH 1/5] cpufreq: Make cpufreq_global_kobject static The cpufreq_global_kobject is only used internally by cpufreq.c after commit 2361be236662 ("cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory"). Make it static. Signed-off-by: Yangtao Li [ rjw: Add empty line after cpufreq_global_kobject definition ] Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq.c | 5 ++--- include/linux/cpufreq.h | 3 --- 2 files changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 4adac3a8c265..cbe6c94bf158 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -105,6 +105,8 @@ bool have_governor_per_policy(void) } EXPORT_SYMBOL_GPL(have_governor_per_policy); +static struct kobject *cpufreq_global_kobject; + struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) { if (have_governor_per_policy()) @@ -2745,9 +2747,6 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver) } EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); -struct kobject *cpufreq_global_kobject; -EXPORT_SYMBOL(cpufreq_global_kobject); - static int __init cpufreq_core_init(void) { if (cpufreq_disabled()) diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index 018dce868de6..0fb561d1b524 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -201,9 +201,6 @@ static inline bool policy_is_shared(struct cpufreq_policy *policy) return cpumask_weight(policy->cpus) > 1; } -/* /sys/devices/system/cpu/cpufreq: entry point for global variables */ -extern struct kobject *cpufreq_global_kobject; - #ifdef CONFIG_CPU_FREQ unsigned int cpufreq_get(unsigned int cpu); unsigned int cpufreq_quick_get(unsigned int cpu); From f0ac20c3f6137910c8a927953e8a92f5b3716166 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 10:07:43 +0100 Subject: [PATCH 2/5] ACPI: EC: Fix flushing of pending work Commit 016b87ca5c8c ("ACPI: EC: Rework flushing of pending work") introduced a subtle bug into the flushing of pending EC work while suspended to idle, which may cause the EC driver to fail to re-enable the EC GPE after handling a non-wakeup event (like a battery status change event, for example). The problem is that the work item flushed by flush_scheduled_work() in __acpi_ec_flush_work() may disable the EC GPE and schedule another work item expected to re-enable it, but that new work item is not flushed, so __acpi_ec_flush_work() returns with the EC GPE disabled and the CPU running it goes into an idle state subsequently. If all of the other CPUs are in idle states at that point, the EC GPE won't be re-enabled until at least one CPU is woken up by another interrupt source, so system wakeup events that would normally come from the EC then don't work. This is reproducible on a Dell XPS13 9360 in my office which sometimes stops reacting to power button and lid events (triggered by the EC on that machine) after switching from AC power to battery power or vice versa while suspended to idle (each of those switches causes the EC GPE to trigger for several times in a row, but they are not system wakeup events). To avoid this problem, it is necessary to drain the workqueue entirely in __acpi_ec_flush_work(), but that cannot be done with respect to system_wq, because work items may be added to it from other places while __acpi_ec_flush_work() is running. For this reason, make the EC driver use a dedicated workqueue for EC events processing (let that workqueue be ordered so that EC events are processed sequentially) and use drain_workqueue() on it in __acpi_ec_flush_work(). Fixes: 016b87ca5c8c ("ACPI: EC: Rework flushing of pending work") Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/ec.c | 44 ++++++++++++++++++++++++++------------------ 1 file changed, 26 insertions(+), 18 deletions(-) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 08bc9751fe66..d1f1cf5d4bf0 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -179,6 +179,7 @@ EXPORT_SYMBOL(first_ec); static struct acpi_ec *boot_ec; static bool boot_ec_is_ecdt = false; +static struct workqueue_struct *ec_wq; static struct workqueue_struct *ec_query_wq; static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ @@ -469,7 +470,7 @@ static void acpi_ec_submit_query(struct acpi_ec *ec) ec_dbg_evt("Command(%s) submitted/blocked", acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); ec->nr_pending_queries++; - schedule_work(&ec->work); + queue_work(ec_wq, &ec->work); } } @@ -535,7 +536,7 @@ static void acpi_ec_enable_event(struct acpi_ec *ec) #ifdef CONFIG_PM_SLEEP static void __acpi_ec_flush_work(void) { - flush_scheduled_work(); /* flush ec->work */ + drain_workqueue(ec_wq); /* flush ec->work */ flush_workqueue(ec_query_wq); /* flush queries */ } @@ -556,8 +557,8 @@ static void acpi_ec_disable_event(struct acpi_ec *ec) void acpi_ec_flush_work(void) { - /* Without ec_query_wq there is nothing to flush. */ - if (!ec_query_wq) + /* Without ec_wq there is nothing to flush. */ + if (!ec_wq) return; __acpi_ec_flush_work(); @@ -2107,25 +2108,33 @@ static struct acpi_driver acpi_ec_driver = { .drv.pm = &acpi_ec_pm, }; -static inline int acpi_ec_query_init(void) +static void acpi_ec_destroy_workqueues(void) { - if (!ec_query_wq) { - ec_query_wq = alloc_workqueue("kec_query", 0, - ec_max_queries); - if (!ec_query_wq) - return -ENODEV; + if (ec_wq) { + destroy_workqueue(ec_wq); + ec_wq = NULL; } - return 0; -} - -static inline void acpi_ec_query_exit(void) -{ if (ec_query_wq) { destroy_workqueue(ec_query_wq); ec_query_wq = NULL; } } +static int acpi_ec_init_workqueues(void) +{ + if (!ec_wq) + ec_wq = alloc_ordered_workqueue("kec", 0); + + if (!ec_query_wq) + ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); + + if (!ec_wq || !ec_query_wq) { + acpi_ec_destroy_workqueues(); + return -ENODEV; + } + return 0; +} + static const struct dmi_system_id acpi_ec_no_wakeup[] = { { .ident = "Thinkpad X1 Carbon 6th", @@ -2156,8 +2165,7 @@ int __init acpi_ec_init(void) int result; int ecdt_fail, dsdt_fail; - /* register workqueue for _Qxx evaluations */ - result = acpi_ec_query_init(); + result = acpi_ec_init_workqueues(); if (result) return result; @@ -2188,6 +2196,6 @@ static void __exit acpi_ec_exit(void) { acpi_bus_unregister_driver(&acpi_ec_driver); - acpi_ec_query_exit(); + acpi_ec_destroy_workqueues(); } #endif /* 0 */ From e3728b50cd9be7d4b1469447cdf1feb93e3b7adb Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 10:11:02 +0100 Subject: [PATCH 3/5] ACPI: PM: s2idle: Avoid possible race related to the EC GPE It is theoretically possible for the ACPI EC GPE to be set after the s2idle_ops->wake() called from s2idle_loop() has returned and before the subsequent pm_wakeup_pending() check is carried out. If that happens, the resulting wakeup event will cause the system to resume even though it may be a spurious one. To avoid that race, first make the ->wake() callback in struct platform_s2idle_ops return a bool value indicating whether or not to let the system resume and rearrange s2idle_loop() to use that value instad of the direct pm_wakeup_pending() call if ->wake() is present. Next, rework acpi_s2idle_wake() to process EC events and check pm_wakeup_pending() before re-arming the SCI for system wakeup to prevent it from triggering prematurely and add comments to that function to explain the rationale for the new code flow. Fixes: 56b991849009 ("PM: sleep: Simplify suspend-to-idle control flow") Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/sleep.c | 44 +++++++++++++++++++++++++++++------------ include/linux/suspend.h | 2 +- kernel/power/suspend.c | 9 +++++---- 3 files changed, 37 insertions(+), 18 deletions(-) diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 439880629839..2c695b196cd2 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -990,21 +990,28 @@ static void acpi_s2idle_sync(void) acpi_os_wait_events_complete(); /* synchronize Notify handling */ } -static void acpi_s2idle_wake(void) +static bool acpi_s2idle_wake(void) { - /* - * If IRQD_WAKEUP_ARMED is set for the SCI at this point, the SCI has - * not triggered while suspended, so bail out. - */ - if (!acpi_sci_irq_valid() || - irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) - return; + if (!acpi_sci_irq_valid()) + return pm_wakeup_pending(); + + while (pm_wakeup_pending()) { + /* + * If IRQD_WAKEUP_ARMED is set for the SCI at this point, the + * SCI has not triggered while suspended, so bail out (the + * wakeup is pending anyway and the SCI is not the source of + * it). + */ + if (irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) + return true; + + /* + * If there are no EC events to process, the wakeup is regarded + * as a genuine one. + */ + if (!acpi_ec_dispatch_gpe()) + return true; - /* - * If there are EC events to process, the wakeup may be a spurious one - * coming from the EC. - */ - if (acpi_ec_dispatch_gpe()) { /* * Cancel the wakeup and process all pending events in case * there are any wakeup ones in there. @@ -1017,8 +1024,19 @@ static void acpi_s2idle_wake(void) acpi_s2idle_sync(); + /* + * The SCI is in the "suspended" state now and it cannot produce + * new wakeup events till the rearming below, so if any of them + * are pending here, they must be resulting from the processing + * of EC events above or coming from somewhere else. + */ + if (pm_wakeup_pending()) + return true; + rearm_wake_irq(acpi_sci_irq); } + + return false; } static void acpi_s2idle_restore_early(void) diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 4a230c2f1c31..2b2055b035ee 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -191,7 +191,7 @@ struct platform_s2idle_ops { int (*begin)(void); int (*prepare)(void); int (*prepare_late)(void); - void (*wake)(void); + bool (*wake)(void); void (*restore_early)(void); void (*restore)(void); void (*end)(void); diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 2c47280fbfc7..8b1bb5ee7e5d 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -131,11 +131,12 @@ static void s2idle_loop(void) * to avoid them upfront. */ for (;;) { - if (s2idle_ops && s2idle_ops->wake) - s2idle_ops->wake(); - - if (pm_wakeup_pending()) + if (s2idle_ops && s2idle_ops->wake) { + if (s2idle_ops->wake()) + break; + } else if (pm_wakeup_pending()) { break; + } pm_wakeup_clear(false); From ea128834dd76f9a72a35d011c651fa96658f06a7 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 17:52:32 +0100 Subject: [PATCH 4/5] ACPICA: Introduce acpi_any_gpe_status_set() Introduce a new helper function, acpi_any_gpe_status_set(), for checking the status bits of all enabled GPEs in one go. It is needed to distinguish spurious SCIs from genuine ones when deciding whether or not to wake up the system from suspend-to-idle. Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/achware.h | 2 + drivers/acpi/acpica/evxfgpe.c | 32 ++++++++++++++++ drivers/acpi/acpica/hwgpe.c | 71 +++++++++++++++++++++++++++++++++++ include/acpi/acpixf.h | 1 + 4 files changed, 106 insertions(+) diff --git a/drivers/acpi/acpica/achware.h b/drivers/acpi/acpica/achware.h index 67f282e9e0af..6ad0517553d5 100644 --- a/drivers/acpi/acpica/achware.h +++ b/drivers/acpi/acpica/achware.h @@ -101,6 +101,8 @@ acpi_status acpi_hw_enable_all_runtime_gpes(void); acpi_status acpi_hw_enable_all_wakeup_gpes(void); +u8 acpi_hw_check_all_gpes(void); + acpi_status acpi_hw_enable_runtime_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info, struct acpi_gpe_block_info *gpe_block, diff --git a/drivers/acpi/acpica/evxfgpe.c b/drivers/acpi/acpica/evxfgpe.c index 2c39ff2a7406..f2de66bfd8a7 100644 --- a/drivers/acpi/acpica/evxfgpe.c +++ b/drivers/acpi/acpica/evxfgpe.c @@ -795,6 +795,38 @@ acpi_status acpi_enable_all_wakeup_gpes(void) ACPI_EXPORT_SYMBOL(acpi_enable_all_wakeup_gpes) +/****************************************************************************** + * + * FUNCTION: acpi_any_gpe_status_set + * + * PARAMETERS: None + * + * RETURN: Whether or not the status bit is set for any GPE + * + * DESCRIPTION: Check the status bits of all enabled GPEs and return TRUE if any + * of them is set or FALSE otherwise. + * + ******************************************************************************/ +u32 acpi_any_gpe_status_set(void) +{ + acpi_status status; + u8 ret; + + ACPI_FUNCTION_TRACE(acpi_any_gpe_status_set); + + status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS); + if (ACPI_FAILURE(status)) { + return (FALSE); + } + + ret = acpi_hw_check_all_gpes(); + (void)acpi_ut_release_mutex(ACPI_MTX_EVENTS); + + return (ret); +} + +ACPI_EXPORT_SYMBOL(acpi_any_gpe_status_set) + /******************************************************************************* * * FUNCTION: acpi_install_gpe_block diff --git a/drivers/acpi/acpica/hwgpe.c b/drivers/acpi/acpica/hwgpe.c index 1b4252bdcd0b..f4c285c2f595 100644 --- a/drivers/acpi/acpica/hwgpe.c +++ b/drivers/acpi/acpica/hwgpe.c @@ -444,6 +444,53 @@ acpi_hw_enable_wakeup_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info, return (AE_OK); } +/****************************************************************************** + * + * FUNCTION: acpi_hw_get_gpe_block_status + * + * PARAMETERS: gpe_xrupt_info - GPE Interrupt info + * gpe_block - Gpe Block info + * + * RETURN: Success + * + * DESCRIPTION: Produce a combined GPE status bits mask for the given block. + * + ******************************************************************************/ + +static acpi_status +acpi_hw_get_gpe_block_status(struct acpi_gpe_xrupt_info *gpe_xrupt_info, + struct acpi_gpe_block_info *gpe_block, + void *ret_ptr) +{ + struct acpi_gpe_register_info *gpe_register_info; + u64 in_enable, in_status; + acpi_status status; + u8 *ret = ret_ptr; + u32 i; + + /* Examine each GPE Register within the block */ + + for (i = 0; i < gpe_block->register_count; i++) { + gpe_register_info = &gpe_block->register_info[i]; + + status = acpi_hw_read(&in_enable, + &gpe_register_info->enable_address); + if (ACPI_FAILURE(status)) { + continue; + } + + status = acpi_hw_read(&in_status, + &gpe_register_info->status_address); + if (ACPI_FAILURE(status)) { + continue; + } + + *ret |= in_enable & in_status; + } + + return (AE_OK); +} + /****************************************************************************** * * FUNCTION: acpi_hw_disable_all_gpes @@ -510,4 +557,28 @@ acpi_status acpi_hw_enable_all_wakeup_gpes(void) return_ACPI_STATUS(status); } +/****************************************************************************** + * + * FUNCTION: acpi_hw_check_all_gpes + * + * PARAMETERS: None + * + * RETURN: Combined status of all GPEs + * + * DESCRIPTION: Check all enabled GPEs in all GPE blocks and return TRUE if the + * status bit is set for at least one of them of FALSE otherwise. + * + ******************************************************************************/ + +u8 acpi_hw_check_all_gpes(void) +{ + u8 ret = 0; + + ACPI_FUNCTION_TRACE(acpi_hw_check_all_gpes); + + (void)acpi_ev_walk_gpe_list(acpi_hw_get_gpe_block_status, &ret); + + return (ret != 0); +} + #endif /* !ACPI_REDUCED_HARDWARE */ diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h index 00994b1b8681..5867777bb7d0 100644 --- a/include/acpi/acpixf.h +++ b/include/acpi/acpixf.h @@ -752,6 +752,7 @@ ACPI_HW_DEPENDENT_RETURN_UINT32(u32 acpi_dispatch_gpe(acpi_handle gpe_device, u3 ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status acpi_disable_all_gpes(void)) ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status acpi_enable_all_runtime_gpes(void)) ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status acpi_enable_all_wakeup_gpes(void)) +ACPI_HW_DEPENDENT_RETURN_UINT32(u32 acpi_any_gpe_status_set(void)) ACPI_HW_DEPENDENT_RETURN_STATUS(acpi_status acpi_get_gpe_device(u32 gpe_index, From fdde0ff8590b4c1c41b3227f5ac4265fccccb96b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 11 Feb 2020 17:53:52 +0100 Subject: [PATCH 5/5] ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system If the platform triggers a spurious SCI even though the status bit is not set for any GPE when the system is suspended to idle, it will be treated as a genuine wakeup, so avoid that by checking if any GPEs are active at all before returning 'true' from acpi_s2idle_wake(). Link: https://bugzilla.kernel.org/show_bug.cgi?id=206413 Fixes: 56b991849009 ("PM: sleep: Simplify suspend-to-idle control flow") Reported-by: Tsuchiya Yuto Cc: 5.4+ # 5.4+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/sleep.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 2c695b196cd2..152f7fc0b200 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -1006,10 +1006,16 @@ static bool acpi_s2idle_wake(void) return true; /* - * If there are no EC events to process, the wakeup is regarded - * as a genuine one. + * If there are no EC events to process and at least one of the + * other enabled GPEs is active, the wakeup is regarded as a + * genuine one. + * + * Note that the checks below must be carried out in this order + * to avoid returning prematurely due to a change of the EC GPE + * status bit from unset to set between the checks with the + * status bits of all the other GPEs unset. */ - if (!acpi_ec_dispatch_gpe()) + if (acpi_any_gpe_status_set() && !acpi_ec_dispatch_gpe()) return true; /*