Subject: [PATCH] base: power: wakeirq: don't leak dev->power.wakeirq

From: [email-masked] (Tony Lindgren)
Date: Tue, 7 Jul 2015 00:40:53 -0700

* Rafael J. Wysocki <[email-masked]> [150706 15:49]:
> On Monday, July 06, 2015 01:01:18 PM Felipe Balbi wrote:
> > on a first call to dev_pm_attach_wake_irq(), if it
> > fails, it will leave dev->power.wakeirq set to a
> > dangling pointer. Instead, let's clear it to make
> > sure a subsequent call to dev_pm_attach_wake_irq()
> > has chance to succeed.
> > 
> > Cc: Tony Lindgren <[email-masked]>
> > Signed-off-by: Felipe Balbi <[email-masked]>
> > ---
> >  drivers/base/power/wakeirq.c | 9 ++++++++-
> >  1 file changed, 8 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c
> > index 7470004ca810..394d250a1ad8 100644
> > --- a/drivers/base/power/wakeirq.c
> > +++ b/drivers/base/power/wakeirq.c
> > @@ -50,9 +50,16 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq,
> >  
> >  	err = device_wakeup_attach_irq(dev, wirq);
> >  	if (err)
> > -		return err;
> > +		goto err_cleanup;
> >  
> >  	return 0;
> > +
> > +err_cleanup:
> > +	spin_lock_irqsave(&dev->power.lock, flags);
> > +	dev->power.wakeirq = NULL;
> > +	spin_unlock_irqrestore(&dev->power.lock, flags);
> > +
> > +	return err;
> >  }
> 
> Too many labels for me and the fact that acquiring of the lock again in the error
> patch doesn't look good.
> 
> However, we can do the entire device_wakeup_attach_irq() under the lock (after
> removing the locking from it), because we're its only caller.
> 
> So what about the below instead (build-tested only)?

Nice, still works for me and simplifies things:

Tested-by: Tony Lindgren <[email-masked]>