| From 60f778fcfc89524ece9fedbd8ae3eecd58adb221 Mon Sep 17 00:00:00 2001 |
| From: Thomas Gleixner <tglx@linutronix.de> |
| Date: Thu, 15 Jul 2010 10:29:00 +0200 |
| Subject: [PATCH] suspend: Prevent might sleep splats |
| |
| commit 60f778fcfc89524ece9fedbd8ae3eecd58adb221 in tip. |
| |
| timekeeping suspend/resume calls read_persistant_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 temporary 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(). |
| |
| Needs to be revisited. |
| |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| |
| diff --git a/include/linux/kernel.h b/include/linux/kernel.h |
| index 45894a4..3f7145e 100644 |
| --- a/include/linux/kernel.h |
| +++ b/include/linux/kernel.h |
| @@ -326,7 +326,7 @@ extern enum system_states { |
| SYSTEM_HALT, |
| SYSTEM_POWER_OFF, |
| SYSTEM_RESTART, |
| - SYSTEM_SUSPEND_DISK, |
| + SYSTEM_SUSPEND, |
| } system_state; |
| |
| #define TAINT_PROPRIETARY_MODULE 0 |
| diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c |
| index bbfe472..18ffa7e 100644 |
| --- a/kernel/power/hibernate.c |
| +++ b/kernel/power/hibernate.c |
| @@ -269,6 +269,8 @@ static int create_image(int platform_mode) |
| |
| local_irq_disable(); |
| |
| + system_state = SYSTEM_SUSPEND; |
| + |
| error = sysdev_suspend(PMSG_FREEZE); |
| if (error) { |
| printk(KERN_ERR "PM: Some system devices failed to power down, " |
| @@ -297,6 +299,7 @@ static int create_image(int platform_mode) |
| */ |
| |
| Enable_irqs: |
| + system_state = SYSTEM_RUNNING; |
| local_irq_enable(); |
| |
| Enable_cpus: |
| @@ -389,6 +392,7 @@ static int resume_target_kernel(bool platform_mode) |
| goto Enable_cpus; |
| |
| local_irq_disable(); |
| + system_state = SYSTEM_SUSPEND; |
| |
| error = sysdev_suspend(PMSG_QUIESCE); |
| if (error) |
| @@ -420,6 +424,7 @@ static int resume_target_kernel(bool platform_mode) |
| sysdev_resume(); |
| |
| Enable_irqs: |
| + system_state = SYSTEM_RUNNING; |
| local_irq_enable(); |
| |
| Enable_cpus: |
| @@ -501,6 +506,7 @@ int hibernation_platform_enter(void) |
| goto Platform_finish; |
| |
| local_irq_disable(); |
| + system_state = SYSTEM_SUSPEND; |
| sysdev_suspend(PMSG_HIBERNATE); |
| hibernation_ops->enter(); |
| /* We should never get here */ |
| diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c |
| index 6f10dfc..72fb4f2 100644 |
| --- a/kernel/power/suspend.c |
| +++ b/kernel/power/suspend.c |
| @@ -154,6 +154,8 @@ static int suspend_enter(suspend_state_t state) |
| arch_suspend_disable_irqs(); |
| BUG_ON(!irqs_disabled()); |
| |
| + system_state = SYSTEM_SUSPEND; |
| + |
| error = sysdev_suspend(PMSG_SUSPEND); |
| if (!error) { |
| if (!suspend_test(TEST_CORE)) |
| @@ -161,6 +163,8 @@ static int suspend_enter(suspend_state_t state) |
| sysdev_resume(); |
| } |
| |
| + system_state = SYSTEM_RUNNING; |
| + |
| arch_suspend_enable_irqs(); |
| BUG_ON(irqs_disabled()); |
| |
| -- |
| 1.7.1.1 |
| |