Re: [PATCH 7/9] drivers/base: fix empty-body warnings in devcoredump.c

[Johannes Berg <johannes@sipsolutions.net>]

On Sat, 2020-04-18 at 12:13 -0700, Matthew Wilcox wrote:
> 
> > > > >  	if (sysfs_create_link(&devcd->devcd_dev.kobj, &dev->kobj,
> > > > >  			      "failing_device"))
> > > > > -		/* nothing - symlink will be missing */;
> > > > > +		do_empty(); /* nothing - symlink will be missing */
> > > > >  
> > > > >  	if (sysfs_create_link(&dev->kobj, &devcd->devcd_dev.kobj,
> > > > >  			      "devcoredump"))
> > > > > -		/* nothing - symlink will be missing */;
> > > > > +		do_empty(); /* nothing - symlink will be missing */
> > > > >  
> > > > >  	INIT_DELAYED_WORK(&devcd->del_wk, devcd_del);
> > > > >  	schedule_delayed_work(&devcd->del_wk, DEVCD_TIMEOUT);
> > > > 
> > > > Could just remove the 'if's?
> > > > 
> > > > +	sysfs_create_link(&devcd->devcd_dev.kobj, &dev->kobj,
> > > > +			"failing_device");
> > > > 
> > > 
> > > OK.
> > 
> > sysfs_create_link is __must_check
> 
> Oh, I missed the declaration -- I just saw the definition.  This is a
> situation where __must_check hurts us and it should be removed.
> 
> Or this code is wrong and it should be
> 
> 	WARN(sysfs_create_link(&devcd->devcd_dev.kobj, &dev->kobj,
> 			"failing_device");

Perhaps it should be. I didn't think it really mattered _that_ much if
the symlink suddenly went missing, but OTOH I don't even know how it
could possibly fail.

johannes