Re: + mm-hugetlb-init-tails-before-init_migratetype.patch added to mm-hotfixes-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 25 Jun 2026 10:49:25 +0800 Muchun Song <muchun.song@linux.dev> wrote:

> > VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page);
> > 
> > This code looks inside the struct page which will be uninitialized
> > for hugetlb tail pages, which will cause a false positive.
> > 
> > So let's initialize the tail pages before this happens.
> > 
>
> ...
>
> 
> Hi Andrew,
> 
> Just a quick heads-up — this bug was actually already fixed in my patch #1 of
> patchset [1].

OK, thanks.  I work through backlog in reverse time order, so that's
still 800 emails away ;)

> Since both patches address the same issue, I'd suggest picking
> mine to avoid unnecessary merge conflicts when the rest of my series gets applied.
>
> Thanks to Michal for also taking a look at this — always good to have extra eyes
> on the same problem.
> 
> [1] https://lore.kernel.org/linux-mm/20260612035903.2468601-2-songmuchun@bytedance.com/

That's a very different change.

I expect I'll need to separate your [01/19] out of the series and make
it a hotfix.

Oh well, thanks, I'll leave a note against
mm-hugetlb-init-tails-before-init_migratetype.patch for now.