Upstreaming - how to deal with vendor fork

[Greg KH]

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