[PATCH RESEND v11 10/13] um: nommu: a work around for MMU dependency to PCI driver

[Hajime Tazaki]

Hello Geert, Johannes,

On Wed, 24 Sep 2025 02:13:47 +0900,
Johannes Berg wrote:
> 
> On Tue, 2025-09-23 at 17:42 +0200, Geert Uytterhoeven wrote:
> > > 
> > > currently, drivers/pci/Kconfig (CONFIG_PCI) marks as depends on MMU,
> > > so we cannot select it when CONFIG_MMU=n.
> > 
> > That is a fairly recent change, see commit 8fe743b5eba0abfb ("PCI:
> > Add CONFIG_MMU dependency") in v6.16-rc1.  As this is not a "hard"
> > dependency, perhaps it should be reverted, iff you are willing to take
> > care of the casual breakage?
> 
> Why though? UML with PCI can't really be a functional thing, only a
> testing thing, and testing PCI on !MMU when that is actually impossible
> in non-simulation is pointless?

currently nommu UML doesn't come with using PCI except building under
kunit (ARCH=um), but I have in my mind to use it under !MMU
environment, so would be an option in the future.

and this series doesn't include PCI w/ !MMU.

so, I would propose the modification to revert the MMU dependency when
time has come.

btw, what do you mean by "hard" dependency in this context, Geert ? 

-- Hajime