This is a note to let you know that I've just added the patch titled PM / wakeirq: Fix unbalanced IRQ enable for wakeirq to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: pm-wakeirq-fix-unbalanced-irq-enable-for-wakeirq.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 69728051f5bf15efaf6edfbcfe1b5a49a2437918 Mon Sep 17 00:00:00 2001 From: Tony Lindgren <tony@xxxxxxxxxxx> Date: Fri, 9 Feb 2018 08:11:26 -0800 Subject: PM / wakeirq: Fix unbalanced IRQ enable for wakeirq From: Tony Lindgren <tony@xxxxxxxxxxx> commit 69728051f5bf15efaf6edfbcfe1b5a49a2437918 upstream. 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 run 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) Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Nobuhiro Iwamatsu (CIP) <nobuhiro1.iwamatsu@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/base/power/wakeirq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/base/power/wakeirq.c +++ b/drivers/base/power/wakeirq.c @@ -320,7 +320,8 @@ void dev_pm_arm_wake_irq(struct wake_irq 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); @@ -342,7 +343,8 @@ void dev_pm_disarm_wake_irq(struct wake_ 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); } } Patches currently in stable-queue which might be from tony@xxxxxxxxxxx are queue-4.4/pm-wakeirq-fix-unbalanced-irq-enable-for-wakeirq.patch