Re: [PATCH 04/11] dma-contiguous: pass the NUMA node to dma_alloc_contiguous()

[Jakub Kicinski <kuba@kernel.org>]

On Thu, 12 Nov 2026 16:43:51 +0100 Paolo Abeni wrote:
> >> I'm possibly over-thinking here, but AFAICS there are a bunch of dma_map_ops that
> >> are using dev_to_node():
> >>
> >> dma_iommu_alloc_coherent() in arch/powerpc/kernel/dma-iommu.c
> >> vio_dma_iommu_alloc_coherent() in arch/powerpc/platforms/pseries/vio.c
> >> gart_alloc_coherent() in arch/x86/kernel/amd_gart_64.c
> >>
> >> With this series they will stop using the driver provided numa node.
> >> Probably not a blocker but possibly worth to call out?  
> > 
> > Nothing "stops" - this series adds a *new* interface by which
> > drivers can now indicate a specific preferred node, but DMA API
> > backends are still free to ignore the caller-provided hint and
> > continue doing whatever they want. This is already called out all
> > over the series in commit messages, documentation and comments
> > including the one above.  
>
> I mean: the series also replaces the old hacks with the new APIs usage
> in a few drivers, and in the above cases there could be actual
> regressions.
> 
> But I guess we could handle them if and when they will surface.

I know AI helps people surface unlikely cases but we need to draw 
the line somewhere.