arm qemu boot failures in -next due to 'PM / Domains: add setter for dev.pm_domain'

[tony@atomide.com (Tony Lindgren)]

* Guenter Roeck <linux@roeck-us.net> [160111 09:51]:
> Hi,
> 
> I see 6 out of 24 arm qemu tests failing in next-20160111. Bisect points
> to commit 989561de9b51 ("PM / Domains: add setter for dev.pm_domain").
> Failures are silent - there is no output on the console.
> Affected tests are
> 
> arm:beagle:multi_v7_defconfig:omap3-beagle
> arm:beaglexm:multi_v7_defconfig:omap3-beagle-xm
> arm:overo:multi_v7_defconfig:omap3-overo-tobi
> arm:beagle:omap2plus_defconfig:omap3-beagle
> arm:beaglexm:omap2plus_defconfig:omap3-beagle-xm
> arm:overo:omap2plus_defconfig:omap3-overo-tobi
> 
> For details please see the 'next' column at http://server.roeck-us.net:8010/builders.
> 
> Reverting the offending commit fixes the problems.
> 
> Please let me know if there is anything I can do to help tracking down the problem.

The following fixes the booting, but I wonder if it's a
proper fix?

--- a/drivers/base/power/common.c
+++ b/drivers/base/power/common.c
@@ -145,9 +145,10 @@ void dev_pm_domain_set(struct device *dev, struct dev_pm_domain *pd)
 {
 	if (dev->pm_domain == pd)
 		return;
-
-	WARN(device_is_bound(dev),
-	     "PM domains can only be changed for unbound devices\n");
+	if (device_is_registered(dev)) {
+		WARN(device_is_bound(dev),
+		     "PM domains can only be changed for unbound devices\n");
+	}
 	dev->pm_domain = pd;
 	device_pm_check_callbacks(dev);
 }