Re: [PATCH] PCI/P2PDMA: Avoid returning a provider for non_mappable_bars

Leon Romanovsky
2026-04-21T19:50:00Z

On Tue, Apr 21, 2026 at 10:43:51AM -0700, Matt Evans wrote:
> Extend pcim_p2pdma_provider()'s checks to exclude functions that have
> pdev->non_mappable_bars set.
>
> Consumers such as VFIO were previously able to map these for access by
> the CPU or P2P. Update the comment on non_mappable_bars to show it
> refers to any access, not just userspace CPU access.
>
> Fixes: 372d6d1b8ae3c ("PCI/P2PDMA: Refactor to separate core P2P functionality from memory allocation")

I don't object to the patch, but this Fixes line doesn't look correct.
non_mappable_bars applies only to s390, which doesn't support p2p. That
wasn't prevented before 372d6d1b8ae3c refactoring too.

Thanks