Re: [PATCH v7 1/1] mm/page_alloc.c: refactor initialization of struct page for holes in memory layout

From: Linus Torvalds
Date: Thu Feb 25 2021 - 13:05:36 EST


On Thu, Feb 25, 2021 at 9:07 AM Mike Rapoport <rppt@xxxxxxxxxxxxx> wrote:
>
> >
> > We might still double-initialize PFNs when two zones overlap within a
> > section, correct?
>
> You mean that a section crosses zones boundary?
> I don't think it's that important.

What if there was a memory allocation in between that could allocate
the once-initialized page?

Maybe it can't happen, or is not an issue for some other reason, but
this code has been fragile and had a ton of subtle issues, so maybe
worth documenting (or explaining here why it's just not relevant)

Linus