[PATCH] Fix NULL ptr dereference in pci_bus_assign_domain_nr() on ARM

[Krzysztof Hałasa]

Hi Bjorn,

Bjorn Helgaas <helgaas at kernel.org> writes:

> On Tue, Mar 01, 2016 at 07:07:18AM +0100, Krzysztof Hałasa wrote:
>> Many ARM platforms use a wrapper:
>> /*
>>  * Compatibility wrapper for older platforms that do not care about
>>  * passing the parent device.
>>  */
>> static inline void pci_common_init(struct hw_pci *hw)
>> {
>>         pci_common_init_dev(NULL, hw);
>> }
>> 
>> which means that pci_bus_assign_domain_nr() can be called without
>> a parent. This patch fixes the NULL pointer dereference.
>
> What exactly is the impact of this?  Does this fix need to be in v4.5?
> It sounds like it should be, but I need a little more detailed
> justification, e.g., "platforms X, Y, Z don't boot at all without
> this change."

At least CNS3xxx doesn't boot. I haven't verified a couple of others,
but they may be broken as well.
-- 
Krzysztof Halasa

Industrial Research Institute for Automation and Measurements PIAP
Al. Jerozolimskie 202, 02-486 Warsaw, Poland