The patch titled Subject: mm/memory_hotplug: use pfn math in place of direct struct page manipulation has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-memory_hotplug-use-pfn-math-in-place-of-direct-struct-page-manipulation.patch
This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...
This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------ From: Zi Yan ziy@nvidia.com Subject: mm/memory_hotplug: use pfn math in place of direct struct page manipulation Date: Wed, 13 Sep 2023 16:12:46 -0400
When dealing with hugetlb pages, manipulating struct page pointers directly can get to wrong struct page, since struct page is not guaranteed to be contiguous on SPARSEMEM without VMEMMAP. Use pfn calculation to handle it properly.
Link: https://lkml.kernel.org/r/20230913201248.452081-4-zi.yan@sent.com Fixes: eeb0efd071d8 ("mm,memory_hotplug: fix scan_movable_pages() for gigantic hugepages") Signed-off-by: Zi Yan ziy@nvidia.com Reviewed-by: Muchun Song songmuchun@bytedance.com Acked-by: David Hildenbrand david@redhat.com Cc: stable@vger.kernel.org Cc: Matthew Wilcox (Oracle) willy@infradead.org Cc: Mike Kravetz mike.kravetz@oracle.com Cc: Mike Rapoport (IBM) rppt@kernel.org Cc: Thomas Bogendoerfer tsbogend@alpha.franken.de Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
mm/memory_hotplug.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/memory_hotplug.c~mm-memory_hotplug-use-pfn-math-in-place-of-direct-struct-page-manipulation +++ a/mm/memory_hotplug.c @@ -1689,7 +1689,7 @@ static int scan_movable_pages(unsigned l */ if (HPageMigratable(head)) goto found; - skip = compound_nr(head) - (page - head); + skip = compound_nr(head) - (pfn - page_to_pfn(head)); pfn += skip - 1; } return -ENOENT; _
Patches currently in -mm which might be from ziy@nvidia.com are
mm-cma-use-nth_page-in-place-of-direct-struct-page-manipulation.patch mm-hugetlb-use-nth_page-in-place-of-direct-struct-page-manipulation.patch mm-memory_hotplug-use-pfn-math-in-place-of-direct-struct-page-manipulation.patch fs-use-nth_page-in-place-of-direct-struct-page-manipulation.patch mips-use-nth_page-in-place-of-direct-struct-page-manipulation.patch