Re: [PATCH] RFC: build-sys: drop dtc submodule

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 8/26/21 9:34 AM, Marc-André Lureau wrote:
> Hi
> 
> On Thu, Aug 26, 2021 at 7:11 AM David Gibson
> <david@gibson.dropbear.id.au <mailto:david@gibson.dropbear.id.au>> wrote:
> 
>     On Thu, Aug 26, 2021 at 12:11:17AM +0400, Marc-André Lureau wrote:
>     > Hi
>     >
>     > On Thu, Aug 26, 2021 at 12:00 AM Peter Maydell
>     <peter.maydell@linaro.org <mailto:peter.maydell@linaro.org>>
>     > wrote:
>     >
>     > > On Wed, 25 Aug 2021 at 20:55, Marc-André Lureau
>     > > <marcandre.lureau@gmail.com <mailto:marcandre.lureau@gmail.com>>
>     wrote:
>     > > > fdt_check_full was added in 1.4.7:
>     > > > https://git.kernel.org/pub/scm/utils/dtc/dtc.git/tag/?h=v1.4.7
>     <https://git.kernel.org/pub/scm/utils/dtc/dtc.git/tag/?h=v1.4.7>
>     > > >
>     > > > Only ubuntu appears to be lagging a bit behind. I wonder if
>     they would
>     > > consider an update.
>     > >
>     > > I doubt it. You would need to wait until that actually falls off
>     > > our supported list. You also have a couple of years to wait until
>     > > Debian oldstable is no longer on our supported list.
>     > >
>     > > Maybe, I don't know why debian oldstable would have received a
>     new version
>     > plus fixes, and not ubuntu.
>     >
>     > It seems we could have our own fallback copy of fdt_check_full()
>     though..
>     > I'll give that a try.
> 
>     We could, but fdt_check_full() is actually a pretty complex function.
> 
> 
> Yeah, that would be used for those who don't have >= 1.4.7.
> 
> Alternatively we could lower the fdt_check_full to fdt_check_header in
> this case? It seems it is used to verify the DT from SLOF. It may be
> trusted I suppose, or a malformed DT may only impact the guest?

Alternative (or complementary?) approach:
https://lore.kernel.org/qemu-devel/20210511155354.3069141-1-philmd@redhat.com/