3.9-rc1 regression in arm dtb build

[swarren@wwwdotorg.org (Stephen Warren)]

On 03/28/2013 01:54 PM, Olof Johansson wrote:
> On Thu, Mar 28, 2013 at 08:33:23PM +0100, Pavel Machek wrote:
>> On Thu 2013-03-28 08:49:20, Stephen Warren wrote:
>>> On 03/28/2013 03:29 AM, Pavel Machek wrote:
>>> ...
>>>> There's change that makes it pretty much impossible to build dtbs
>>>> reliably between different kernel versions, because it leaves old dtbs
>>>> around, and they survive even make clean.
>>>
>>> One question here: Presumably the dtbs don't survive "make clean" if you
>>> run that right after building the dtbs, but only if you check out a new
>>> kernel version before running clean? Or is that not the case?
>>
>> That was the case I seen, yes.
>>
>> Have old kernel running, dtbs building. Apply a patch. It starts
>> behaving weird. You do make clean... but you still get old dtbs.
>>
>> (It would be nice if make socfpga_cyclone5.dtb would magically remove
>> all the dtbs from old location; make dtbs does that if I understand
>> stuff correctly).
> 
> 
> This takes care of the "make dtbs" case (or just "make" case), but not
> when you build a specific target.

I guess to really solve this, we need the following changes:

In the all kernels:

For both arch/*/boot and arch/*/boot/dts: clean removes *.dtb

In kernels that build *.dtb in the new location:

make dtbs and make foo.dtb both rm ../*.dtb

In kernels that build *.dtb in the old location:

make dtbs and make foo.dtb both rm dts/*.dtb

Is that too much to retrofit into all the stable kernels?