Upstreaming - how to deal with vendor fork

[Linus Probert]

On Thu Apr 30, 2026 at 9:15 AM CEST, Greg KH wrote:
> On Wed, Apr 29, 2026 at 07:42:14PM +0200, Linus Probert wrote:
>> On Wed Apr 29, 2026 at 3:27 PM CEST, Patryk wrote:
>> > Hi
>> > Some time ago I managed to upstream one bugfix, now I have more changes but
>> > I'm wondering how to approach this.
>> >
>> > Suppose that I have found a bug and prepared a fix. However, the bug and
>> > its solution has been found and tested on a custom board that is equipped
>> > with a particular buggy device. The problem is that I cannot simply use
>> > mainline/maintainer tree, build it, and run on my board as these source
>> > trees do not have support for my board, as I use SoC vendor fork (v6.12)
>> > supplied with their bsp with patches that add support for my board.
>> >
>> > It's not mine decision - obviously - me and my team would be very willing
>> > to use mainline but it would require some effort, time and obviously we
>> > would not get vendor support in case of some bugs (it happened mamy times).
>> >
>> > I can of course take the minimal set of patches for out board and apply
>> > them over mainline but e.g. now I have a bugfix for mainline driver...but
>> > in order to fully test it I need vendor changes as they did not upstream it
>> > yet.
>> >
>> > So at the end in order to test a bugfix on the mainline I would need to
>> > apply patches that add support for my board as well patches from vendor
>> > fork that add support for the rest of the functionality (not yet upstreamed
>> > by vendor) that I need in order to test the bugfix.
>> >
>> > Any sugestion on how to approach this? I have already few changes that
>> > could be applied to mainline but due to what I described above they're just
>> > waiting...
>> >
>> > Will be grateful for some sugestion.
>> >
>> > Best regards
>> > Patryk
>> 
>> Hi Patryk,
>> 
>> if your patches can't be applied without first applying the vendors
>> patches then there's not much you can do is there. Your fixes won't
>> apply.
>> 
>> If your patches do apply to staging-next and they do fix your issue
>> isn't that enough to submit them? You should be able to explain how you
>> have confirmed the fixes even though it requires some steps to get
>> there.
>> 
>> You can always submit a patch-tree to linux-staging with an RFC prefix
>> and you will get feedback based on that. Either you get a no or a yes.
>> Worth testing IMO.
>
> What does the staging tree have to do with this?
>
> confused,
>
> greg k-h

Nothing most likely. Patryk should use an appropriate tree for his fixes
if they are applicable. The driver was never named. I mostly look at the
staging tree so it was fresh on my mind. Freudian slip if you will.

Br,
Linus