From 2ef7c01c0cdb170142058c6d8fe0697aee4e4d7d Mon Sep 17 00:00:00 2001 From: Doug Berger Date: Wed, 25 Apr 2018 16:40:30 -0700 Subject: PM / wakeup: Only update last time for active wakeup sources When wakelock support was added, the wakeup_source_add() function was updated to set the last_time value of the wakeup source. This has the unintended side effect of producing confusing output from pm_print_active_wakeup_sources() when a wakeup source is added prior to a sleep that is blocked by a different wakeup source. The function pm_print_active_wakeup_sources() will search for the most recently active wakeup source when no active source is found. If a wakeup source is added after a different wakeup source blocks the system from going to sleep it may have a later last_time value than the blocking source and be output as the last active wakeup source even if it has never actually been active. It looks to me like the change to wakeup_source_add() was made to prevent the wakelock garbage collection from accidentally dropping a wakelock during the narrow window between adding the wakelock to the wakelock list in wakelock_lookup_add() and the activation of the wakeup source in pm_wake_lock(). This commit changes the behavior so that only the last_time of the wakeup source used by a wakelock is initialized prior to adding it to the wakeup source list. This preserves the meaning of the last_time value as the last time the wakeup source was active and allows a wakeup source that has never been active to have a last_time value of 0. Fixes: b86ff9820fd5 (PM / Sleep: Add user space interface for manipulating wakeup sources, v3) Signed-off-by: Doug Berger Signed-off-by: Rafael J. Wysocki --- kernel/power/wakelock.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/power') diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c index dfba59be190b..4210152e56f0 100644 --- a/kernel/power/wakelock.c +++ b/kernel/power/wakelock.c @@ -188,6 +188,7 @@ static struct wakelock *wakelock_lookup_add(const char *name, size_t len, return ERR_PTR(-ENOMEM); } wl->ws.name = wl->name; + wl->ws.last_time = ktime_get(); wakeup_source_add(&wl->ws); rb_link_node(&wl->node, parent, node); rb_insert_color(&wl->node, &wakelocks_tree); -- cgit v1.2.3 From c1a957d17086d20d52d7f9c8dffaeac2ee09d6f9 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 25 May 2018 17:54:41 +0200 Subject: PM / suspend: Prevent might sleep splats timekeeping suspend/resume calls read_persistent_clock() which takes rtc_lock. That results in might sleep warnings because at that point we run with interrupts disabled. We cannot convert rtc_lock to a raw spinlock as that would trigger other might sleep warnings. As a workaround we disable the might sleep warnings by setting system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock contention because hibernate / suspend to RAM is single-CPU at this point. In s2idle's case the system_state is set to SYSTEM_SUSPEND before timekeeping_suspend() which is invoked by the last CPU. In the resume case it set back to SYSTEM_RUNNING after timekeeping_resume() which is invoked by the first CPU in the resume case. The other CPUs will block on tick_freeze_lock. Signed-off-by: Thomas Gleixner [bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()] Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki --- include/linux/kernel.h | 1 + kernel/power/hibernate.c | 7 +++++++ kernel/power/suspend.c | 4 ++++ kernel/time/tick-common.c | 2 ++ 4 files changed, 14 insertions(+) (limited to 'kernel/power') diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 6a1eb0b0aad9..7aed92624531 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -542,6 +542,7 @@ extern enum system_states { SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; /* This cannot be an enum because some may be used in assembly source. */ diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 5454cc639a8d..9c85c7822383 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -287,6 +287,8 @@ static int create_image(int platform_mode) local_irq_disable(); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (error) { pr_err("Some system devices failed to power down, aborting hibernation\n"); @@ -317,6 +319,7 @@ static int create_image(int platform_mode) syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -445,6 +448,7 @@ static int resume_target_kernel(bool platform_mode) goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) @@ -478,6 +482,7 @@ static int resume_target_kernel(bool platform_mode) syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -563,6 +568,7 @@ int hibernation_platform_enter(void) goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; @@ -575,6 +581,7 @@ int hibernation_platform_enter(void) Power_up: syscore_resume(); + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 4c10be0f4843..5149c77506b3 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -428,6 +428,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (!error) { *wakeup = pm_wakeup_pending(); @@ -443,6 +445,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) syscore_resume(); } + system_state = SYSTEM_RUNNING; + arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 49edc1c4f3e6..14de3727b18e 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -490,6 +490,7 @@ void tick_freeze(void) if (tick_freeze_depth == num_online_cpus()) { trace_suspend_resume(TPS("timekeeping_freeze"), smp_processor_id(), true); + system_state = SYSTEM_SUSPEND; timekeeping_suspend(); } else { tick_suspend_local(); @@ -513,6 +514,7 @@ void tick_unfreeze(void) if (tick_freeze_depth == num_online_cpus()) { timekeeping_resume(); + system_state = SYSTEM_RUNNING; trace_suspend_resume(TPS("timekeeping_freeze"), smp_processor_id(), false); } else { -- cgit v1.2.3 From 9c8cd6b62f39658e5f5db08fcead686905b85ff9 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 25 May 2018 11:46:47 +0200 Subject: PM / s2idle: Make s2idle_wait_head swait based s2idle_wait_head is used during s2idle with interrupts disabled even on RT. There is no "custom" wake up function so swait could be used instead which is also lower weight compared to the wait_queue. Make s2idle_wait_head a swait_queue_head. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki --- kernel/power/suspend.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'kernel/power') diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 5149c77506b3..1020f597ff14 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -57,7 +58,7 @@ EXPORT_SYMBOL_GPL(pm_suspend_global_flags); static const struct platform_suspend_ops *suspend_ops; static const struct platform_s2idle_ops *s2idle_ops; -static DECLARE_WAIT_QUEUE_HEAD(s2idle_wait_head); +static DECLARE_SWAIT_QUEUE_HEAD(s2idle_wait_head); enum s2idle_states __read_mostly s2idle_state; static DEFINE_SPINLOCK(s2idle_lock); @@ -91,8 +92,8 @@ static void s2idle_enter(void) /* Push all the CPUs into the idle loop. */ wake_up_all_idle_cpus(); /* Make the current CPU wait so it can enter the idle loop too. */ - wait_event(s2idle_wait_head, - s2idle_state == S2IDLE_STATE_WAKE); + swait_event(s2idle_wait_head, + s2idle_state == S2IDLE_STATE_WAKE); cpuidle_pause(); put_online_cpus(); @@ -159,7 +160,7 @@ void s2idle_wake(void) spin_lock_irqsave(&s2idle_lock, flags); if (s2idle_state > S2IDLE_STATE_NONE) { s2idle_state = S2IDLE_STATE_WAKE; - wake_up(&s2idle_wait_head); + swake_up(&s2idle_wait_head); } spin_unlock_irqrestore(&s2idle_lock, flags); } -- cgit v1.2.3 From 62fc00a6611a0014c85763f9def1fc07c15d1302 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 25 May 2018 11:46:48 +0200 Subject: PM / wakeup: Make s2idle_lock a RAW_SPINLOCK The `s2idle_lock' is acquired during suspend while interrupts are disabled even on RT. The lock is acquired for short sections only. Make it a RAW lock which avoids "sleeping while atomic" warnings on RT. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Rafael J. Wysocki --- kernel/power/suspend.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'kernel/power') diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 1020f597ff14..87331565e505 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -61,7 +61,7 @@ static const struct platform_s2idle_ops *s2idle_ops; static DECLARE_SWAIT_QUEUE_HEAD(s2idle_wait_head); enum s2idle_states __read_mostly s2idle_state; -static DEFINE_SPINLOCK(s2idle_lock); +static DEFINE_RAW_SPINLOCK(s2idle_lock); void s2idle_set_ops(const struct platform_s2idle_ops *ops) { @@ -79,12 +79,12 @@ static void s2idle_enter(void) { trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, true); - spin_lock_irq(&s2idle_lock); + raw_spin_lock_irq(&s2idle_lock); if (pm_wakeup_pending()) goto out; s2idle_state = S2IDLE_STATE_ENTER; - spin_unlock_irq(&s2idle_lock); + raw_spin_unlock_irq(&s2idle_lock); get_online_cpus(); cpuidle_resume(); @@ -98,11 +98,11 @@ static void s2idle_enter(void) cpuidle_pause(); put_online_cpus(); - spin_lock_irq(&s2idle_lock); + raw_spin_lock_irq(&s2idle_lock); out: s2idle_state = S2IDLE_STATE_NONE; - spin_unlock_irq(&s2idle_lock); + raw_spin_unlock_irq(&s2idle_lock); trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_TO_IDLE, false); } @@ -157,12 +157,12 @@ void s2idle_wake(void) { unsigned long flags; - spin_lock_irqsave(&s2idle_lock, flags); + raw_spin_lock_irqsave(&s2idle_lock, flags); if (s2idle_state > S2IDLE_STATE_NONE) { s2idle_state = S2IDLE_STATE_WAKE; swake_up(&s2idle_wait_head); } - spin_unlock_irqrestore(&s2idle_lock, flags); + raw_spin_unlock_irqrestore(&s2idle_lock, flags); } EXPORT_SYMBOL_GPL(s2idle_wake); -- cgit v1.2.3 From fc14eebfc20854a38fd9f1d93a42b1783dad4d17 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Sat, 26 May 2018 09:59:36 +0900 Subject: PM / hibernate: Fix oops at snapshot_write() syzbot is reporting NULL pointer dereference at snapshot_write() [1]. This is because data->handle is zero-cleared by ioctl(SNAPSHOT_FREE). Fix this by checking data_of(data->handle) != NULL before using it. [1] https://syzkaller.appspot.com/bug?id=828a3c71bd344a6de8b6a31233d51a72099f27fd Signed-off-by: Tetsuo Handa Reported-by: syzbot Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'kernel/power') diff --git a/kernel/power/user.c b/kernel/power/user.c index 75c959de4b29..abd225550271 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -186,6 +186,11 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, res = PAGE_SIZE - pg_offp; } + if (!data_of(data->handle)) { + res = -EINVAL; + goto unlock; + } + res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp, buf, count); if (res > 0) -- cgit v1.2.3 From 74cd8171c42fcb0a0d55575dd036239b7325a455 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 25 May 2018 12:33:10 +0200 Subject: PM / QoS: Drop redundant declaration of pm_qos_get_value() The extra forward declaration of pm_qos_get_value() is redundant, so drop it. Signed-off-by: Rafael J. Wysocki --- kernel/power/qos.c | 1 - 1 file changed, 1 deletion(-) (limited to 'kernel/power') diff --git a/kernel/power/qos.c b/kernel/power/qos.c index fa39092b7aea..86d72ffb811b 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -184,7 +184,6 @@ static inline void pm_qos_set_value(struct pm_qos_constraints *c, s32 value) c->target_value = value; } -static inline int pm_qos_get_value(struct pm_qos_constraints *c); static int pm_qos_dbg_show_requests(struct seq_file *s, void *unused) { struct pm_qos_object *qos = (struct pm_qos_object *)s->private; -- cgit v1.2.3