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

[Rafael J. Wysocki]

On Tue, Jan 12, 2016 at 1:15 AM, Tony Lindgren <tony at atomide.com> wrote:
> * Guenter Roeck <linux at roeck-us.net> [160111 15:40]:
>> On 01/11/2016 02:49 PM, Rafael J. Wysocki wrote:
>> >On Monday, January 11, 2016 12:04:50 PM Guenter Roeck wrote:
>> >>On Mon, Jan 11, 2016 at 10:55:00AM -0800, Tony Lindgren wrote:
>> >>>* Guenter Roeck <linux at 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
>> >>
>> >>Yes, it does.
>> >>
>> >>Tested-by: Guenter Roeck <linux at roeck-us.net>
>> >>
>> >>>proper fix?
>> >>>
>> >>That I don't know.
>> >
>> >If I'm not mistaken, what happens is that device_is_bound() tries to
>> >dereference dev->p which is NULL.  If that's the case, the appended one
>> >should help too.
>> >
>> >Can you please check?
>> >
>> >---
>> >  drivers/base/dd.c |    2 +-
>> >  1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> >Index: linux-pm/drivers/base/dd.c
>> >===================================================================
>> >--- linux-pm.orig/drivers/base/dd.c
>> >+++ linux-pm/drivers/base/dd.c
>> >@@ -234,7 +234,7 @@ late_initcall(deferred_probe_initcall);
>> >   */
>> >  bool device_is_bound(struct device *dev)
>> >  {
>> >-    return klist_node_attached(&dev->p->knode_driver);
>> >+    return dev->p && klist_node_attached(&dev->p->knode_driver);
>>
>> Yes, that fixes the problem as well.
>
> Yeah works for me too:
>
> Tested-by: Tony Lindgren <tony at atomide.com>

OK, thanks!

I'll add a changelog to this one and queue it up then.

Thanks,
Rafael