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

[Guenter Roeck]

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.

Guenter