From b0bf64af36862b84d84f5b752a50858124b3db6b Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 15 Jul 2010 10:29:00 +0200 Subject: [PATCH] suspend: Prevent might sleep splats 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 Signed-off-by: azrim --- include/linux/kernel.h | 1 + kernel/power/hibernate.c | 7 +++++++ kernel/power/suspend.c | 4 ++++ 3 files changed, 12 insertions(+) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 122687efa727..c2711dcc0bb6 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -533,6 +533,7 @@ extern enum system_states { SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; #define TAINT_PROPRIETARY_MODULE 0 diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 3c84786b4141..099a7f0564c9 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -293,6 +293,8 @@ 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"); @@ -323,6 +325,7 @@ static int create_image(int platform_mode) syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -456,6 +459,7 @@ static int resume_target_kernel(bool platform_mode) goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) @@ -489,6 +493,7 @@ static int resume_target_kernel(bool platform_mode) syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -574,6 +579,7 @@ int hibernation_platform_enter(void) goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; @@ -586,6 +592,7 @@ 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 af60a1fabda0..a4b48c9fe3ea 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -441,6 +441,8 @@ 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(); @@ -457,6 +459,8 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) syscore_resume(); } + system_state = SYSTEM_RUNNING; + arch_suspend_enable_irqs(); BUG_ON(irqs_disabled());