Commit 6d3dab7d authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PM / wakeirq: Avoid setting power.wakeirq too hastily 



If dev_pm_attach_wake_irq() fails, the device's power.wakeirq field
should not be set to point to the struct wake_irq passed to that
function, as that object will be freed going forward.

For this reason, make dev_pm_attach_wake_irq() first call
device_wakeup_attach_irq() and only set the device's power.wakeirq
field if that's successful.

That requires device_wakeup_attach_irq() to be called under the
device's power.lock lock, but since dev_pm_attach_wake_irq() is
the only caller of it, the requisite changes are easy to make.

Fixes: 4990d4fe (PM / Wakeirq: Add automated device wake IRQ handling)
Reported-by: default avatarFelipe Balbi <balbi@ti.com>
Tested-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent db874c7e

drivers/base/power/wakeirq.c

+5 −7
Original line number Diff line number Diff line
@@ -45,14 +45,12 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq, 
		return -EEXIST;

	}



	err = device_wakeup_attach_irq(dev, wirq);

	if (!err)

		dev->power.wakeirq = wirq;

	spin_unlock_irqrestore(&dev->power.lock, flags);



	err = device_wakeup_attach_irq(dev, wirq);

	if (err)

	spin_unlock_irqrestore(&dev->power.lock, flags);

	return err;



	return 0;

}



/**
@@ -105,10 +103,10 @@ void dev_pm_clear_wake_irq(struct device *dev) 
		return;



	spin_lock_irqsave(&dev->power.lock, flags);

	device_wakeup_detach_irq(dev);

	dev->power.wakeirq = NULL;

	spin_unlock_irqrestore(&dev->power.lock, flags);



	device_wakeup_detach_irq(dev);

	if (wirq->dedicated_irq)

		free_irq(wirq->irq, wirq);

	kfree(wirq);

drivers/base/power/wakeup.c

+10 −21
Original line number Diff line number Diff line
@@ -247,32 +247,25 @@ EXPORT_SYMBOL_GPL(device_wakeup_enable); 
 * Attach a device wakeirq to the wakeup source so the device

 * wake IRQ can be configured automatically for suspend and

 * resume.

 *

 * Call under the device's power.lock lock.

 */

int device_wakeup_attach_irq(struct device *dev,

			     struct wake_irq *wakeirq)

{

	struct wakeup_source *ws;

	int ret = 0;



	spin_lock_irq(&dev->power.lock);

	ws = dev->power.wakeup;

	if (!ws) {

		dev_err(dev, "forgot to call call device_init_wakeup?\n");

		ret = -EINVAL;

		goto unlock;

		return -EINVAL;

	}



	if (ws->wakeirq) {

		ret = -EEXIST;

		goto unlock;

	}

	if (ws->wakeirq)

		return -EEXIST;



	ws->wakeirq = wakeirq;



unlock:

	spin_unlock_irq(&dev->power.lock);



	return ret;

	return 0;

}



/**
@@ -280,20 +273,16 @@ unlock: 
 * @dev: Device to handle

 *

 * Removes a device wakeirq from the wakeup source.

 *

 * Call under the device's power.lock lock.

 */

void device_wakeup_detach_irq(struct device *dev)

{

	struct wakeup_source *ws;



	spin_lock_irq(&dev->power.lock);

	ws = dev->power.wakeup;

	if (!ws)

		goto unlock;



	if (ws)

		ws->wakeirq = NULL;



unlock:

	spin_unlock_irq(&dev->power.lock);

}



/**

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