Re: [PATCH] PM: Fix dev_pm_put_subsys_data() to not call kfree() while holding device power lock

[Shuah Khan <shuah.kh@samsung.com>]

On Mon, 2013-05-06 at 08:00 -0600, Shuah Khan wrote:
> On Mon, 2013-05-06 at 14:09 +0200, Pavel Machek wrote:
> > Hi!
> > 
> > > > Wow, that function is fragile. It returns 0/1/-EINVAL, while being
> > > > documented for 0/1...
> > > 
> > > Oh, it generally should return 1 for !psd.
> > > 
> > > > Patch does not look obviously wrong, but maybe 
> > > > 
> > > > @@ -73,13 +73,17 @@ int dev_pm_put_subsys_data(struct device *dev)
> > > >  
> > > >  	if (--psd->refcount == 0) {
> > > >  		dev->power.subsys_data = NULL;
> > > > +		spin_unlock_irq(&dev->power.lock);
> > > > -		kfree(psd);
> > > > - 		ret = 1;
> > > > +		return 1;
> > > >  	}
> > > > 
> > > > Would be cleaner.
> > > 
> > > What about this:
> > 
> > Looks good to me.
> > 
> > Reviewed-by: Pavel Machek <pavel@ucw.cz>
> 
> Rafael/Pavel,
> 
> I redid the patch based on Pavel's comments and just about to send it
> and then I saw your exchange. This version looks good to me. Do you want
> me to test the patch and resend?
> 
> thanks,
> -- Shuah

I sent v2 patch that incorporates the comments from Rafael and Pavel.

thanks,

-- Shuah

Shuah Khan Lead Kernel Developer - Open Source Group 
Samsung Research America (Silicon Valley)
shuah.kh@samsung.com | (970) 672-0658