Re: [PATCH] of: Kconfig: OF_OVERLAY, select OF_EARLY_FLATTREE

From: Frank Rowand
Date: Thu Mar 01 2018 - 11:14:13 EST


On 02/28/18 13:44, Frank Rowand wrote:
> On 02/28/18 12:26, Rob Herring wrote:
>> Sorry for the delay, been away for a few days.
>>
>> On Mon, Feb 19, 2018 at 12:24 AM, Frank Rowand <frowand.list@xxxxxxxxx> wrote:
>>>
>>> On 02/18/18 17:46, Rob Herring wrote:
>>>> On Sun, Feb 18, 2018 at 6:29 PM, <frowand.list@xxxxxxxxx> wrote:
>>>>> From: Frank Rowand <frank.rowand@xxxxxxxx>
>>>>>
>>>>> kbuild test robot reported a new warning for a recent patch:
>>>>>>> drivers/of/overlay.c:832:2: error: implicit declaration of function 'of_fdt_unflatten_tree' [-Werror=implicit-function-declaration]
>>>>> of_fdt_unflatten_tree(new_fdt, NULL, &overlay_root);
>>>>>
>>>>> The cause is that the prototype for of_fdt_unflatten_tree() in
>>>>> include/linux/of_fdt.c is guarded by OF_EARLY_FLATTREE.
>>
>> Umm, this is not true. of_fdt_unflatten_tree is outside the ifdef for
>> OF_EARLY_FLATTREE.
>
> Brown paper bag. :-( As you note below, CONFIG_OF_FLATTREE is the
> relevant option.


< snip >

> function, so it seems all is OK from that angle. But all use of overlays
> for many previous releases requires manually selecting OF_FLATTREE, given
> that FDTs have been the overlay source.

I was not correct about needing to manually select OF_FLATTREE. For
the unittest of overlays, which did the overlay unflattening, OF_UNITTEST
selected (selects until my other patch series) OF_EARLY_FLATTREE, which
selects OF_FLATTREE.

-Frank