Re: [PATCH v3 0/5] Use nth_page() in place of direct struct page manipulation

Andrew Morton
2023-09-13T21:12:08Z

On Wed, 13 Sep 2023 16:12:43 -0400 Zi Yan <zi.yan@sent.com> wrote:

> On SPARSEMEM without VMEMMAP, struct page is not guaranteed to be
> contiguous, since each memory section's memmap might be allocated
> independently. hugetlb pages can go beyond a memory section size, thus
> direct struct page manipulation on hugetlb pages/subpages might give
> wrong struct page. Kernel provides nth_page() to do the manipulation
> properly. Use that whenever code can see hugetlb pages.

for (each patch) {

Can we please explain why -stable backporting is recommended?

Such an explanation will, as always, include a description of the
user-visible effects of the bug.

Some of the Fixes: targets are very old: 5 years. Has something
changed to bring these flaws to light? Or is it from code inspection?
}

Thanks.