Re: [GIT PULL] MM updates for 6.13-rc1

From: Matthew Wilcox
Date: Sat Nov 23 2024 - 17:01:43 EST


On Thu, Nov 21, 2024 at 09:42:29PM -0800, Andrew Morton wrote:
> It isn't only Huawai people. David acked Gaosheng's patch and it snuck
> past me (again). People keep on getting tricked by this idiom and I
> think we'd be better off with some nicely named wrapper to help
> readers understand what's going on.

This whole discussion has got out of hand. The solution is to divorce
page and folio, and I think we can get there in 3-4 more merge windows,
at least with a CONFIG option.

And this is where &folio->page is USEFUL because it clearly marks all
the places that need to be fixed. As I've been saying to people all
along, while folio_page(folio, 0) and &folio->page are the same today,
they have completely different semantics. That hasn't stopped people
from getting it wrong, but some people can't be helped.

Don't bother coming up with clever new ways for people to get this
wrong. Let's get this project over the finish line.