Re: [PATCH 01/16] PCI/P2PDMA: Pass gfp_mask flags to upstream_bridge_distance_warn()

[Christoph Hellwig]

On Mon, May 03, 2021 at 11:17:31AM -0700, John Hubbard wrote:
> That's the thing: memory failure should be exceedingly rare for this.
> Therefore, just fail out entirely (which I don't expect we'll likely
> ever see), instead of doing all this weird stuff to try to continue
> on if you cannot allocate a single page. If you are in that case, the
> system is not in a state that is going to run your dma p2p setup well
> anyway.
>
> I think it's *less* complexity to allocate up front, fail early if
> allocation fails, and then not have to deal with these really odd
> quirks at the lower levels.

Agreed.