Re: [PATCH] PM / wakeirq: Fix unbalanced irq enable for wakeirq

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Friday, February 9, 2018 5:11:26 PM CET Tony Lindgren wrote:
> If a device is runtime PM suspended when we enter suspend and has
> a dedicated wake irq, we can get the following warning:
> 
> WARNING: CPU: 0 PID: 108 at kernel/irq/manage.c:526 enable_irq+0x40/0x94
> [  102.087860] Unbalanced enable for IRQ 147
> ...
> (enable_irq) from [<c06117a8>] (dev_pm_arm_wake_irq+0x4c/0x60)
> (dev_pm_arm_wake_irq) from [<c0618360>]
>  (device_wakeup_arm_wake_irqs+0x58/0x9c)
> (device_wakeup_arm_wake_irqs) from [<c0615948>]
> (dpm_suspend_noirq+0x10/0x48)
> (dpm_suspend_noirq) from [<c01ac7ac>]
> (suspend_devices_and_enter+0x30c/0xf14)
> (suspend_devices_and_enter) from [<c01adf20>]
> (enter_state+0xad4/0xbd8)
> (enter_state) from [<c01ad3ec>] (pm_suspend+0x38/0x98)
> (pm_suspend) from [<c01ab3e8>] (state_store+0x68/0xc8)
> 
> This is because the dedicated wake irq for the device may have been
> already enabled earlier by dev_pm_enable_wake_irq_check(). Fix the
> issue by checking for runtime PM suspended status.
> 
> This issue can be easily reproduced by setting serial console log level
> to zero, letting the serial console idle, and suspend the system from
> an ssh terminal. On resume, dmesg will have the warning above.
> 
> The reason why I have not ran into this issue earlier has been that I
> typically run my PM test cases from on a serial console instead over ssh.
> 
> Fixes: c84345597558 ("PM / wakeirq: Enable dedicated wakeirq for suspend")
> Cc: Brian Norris <briannorris@chromium.org>
> Cc: Grygorii Strashko <grygorii.strashko@ti.com>
> Cc: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Tony Lindgren <tony@atomide.com>
> ---
>  drivers/base/power/wakeirq.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c
> --- a/drivers/base/power/wakeirq.c
> +++ b/drivers/base/power/wakeirq.c
> @@ -321,7 +321,8 @@ void dev_pm_arm_wake_irq(struct wake_irq *wirq)
>  		return;
>  
>  	if (device_may_wakeup(wirq->dev)) {
> -		if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)
> +		if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
> +		    !pm_runtime_status_suspended(wirq->dev))
>  			enable_irq(wirq->irq);
>  
>  		enable_irq_wake(wirq->irq);
> @@ -343,7 +344,8 @@ void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
>  	if (device_may_wakeup(wirq->dev)) {
>  		disable_irq_wake(wirq->irq);
>  
> -		if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED)
> +		if (wirq->status & WAKE_IRQ_DEDICATED_ALLOCATED &&
> +		    !pm_runtime_status_suspended(wirq->dev))
>  			disable_irq_nosync(wirq->irq);
>  	}
>  }
> 

Applied, thanks!