Re: running "make dtbs" for test builds

[Fengguang Wu]

Hi Arnd,

On Mon, Jul 18, 2016 at 02:01:17PM +0200, Arnd Bergmann wrote:
> Hi Fengguang,
>
> I've recently run into a number of cases in which I pulled a branch that
> was building fine with "make vmlinux", but that failed for "make dtbs",
> and I wonder if this is something that could be checked by the kbuild
> test robot so we catch it earlier.

Yes, sure.

> There are parts of this:
>
> - running "make" without a target will build the default image file
>  and also do the "dtbs" target on ARM and other architectures. I
>  don't know if this is what you do, or if you always build

My typical build command sequences are

       make oldnoconfig
       make prepare
       make headers_install
       make ARCH=xxx
       make install

So it looks good already. :)

>  "make vmlinux ; make modules", which doesn't include it.
>  The dtbs makefile target is available on arc, arm, arm64, h8300,
>  metag, mips, nios2, and xtensa but not the others, so if you
>  call it explicitly, that has to be in an architecture specific
>  way.

Got it.

> - setting CONFIG_OF_ALL_DTBS will catch all files, not just the
>  ones that are built by default for the set of configurations you
>  have. It's possible to simply override this on the command line,
>  using "make CONFIG_OF_ALL_DTBS=y", it doesn't actually have to
>  be part of the configuration. The result is independent of the
>  actual configuration, so it should be enough to do this once
>  per architecture and source revision.
>
> Is this something you can add?

Do you mean to simply change the main "make" command line to

       make ARCH=xxx CONFIG_OF_ALL_DTBS=y

Which looks safe even for ARCHs that do not support it.

The arch/.../Makefile that actually use it are:

       arch/arc/boot/dts/Makefile
       arch/arm/boot/dts/Makefile
       arch/arm64/boot/dts/Makefile
       arch/h8300/boot/dts/Makefile
       arch/metag/boot/dts/Makefile
       arch/mips/boot/dts/Makefile
       arch/xtensa/boot/dts/Makefile

Regards,
Fengguang