+ mips-use-nth_page-in-place-of-direct-struct-page-manipulation.patch added to mm-hotfixes-unstable branch

+ mips-use-nth_page-in-place-of-direct-struct-page-manipulation.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mips: use nth_page() in place of direct struct page manipulation
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mips-use-nth_page-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/mips-use-nth_page-in-place-of-direct-struct-page-manipulation.patch

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: mips: use nth_page() in place of direct struct page manipulation
Date: Wed, 13 Sep 2023 16:12:48 -0400

__flush_dcache_pages() is called during hugetlb migration via
migrate_pages() -> migrate_hugetlbs() -> unmap_and_move_huge_page() ->
move_to_new_folio() -> flush_dcache_folio().  And with hugetlb and without
sparsemem vmemmap, struct page is not guaranteed to be contiguous beyond a
section.  Use nth_page() instead.

Link: https://lkml.kernel.org/r/20230913201248.452081-6-zi.yan@sent.com
Fixes: 15fa3e8e3269 ("mips: implement the new page table range API")
Signed-off-by: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/mips/mm/cache.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/mm/cache.c~mips-use-nth_page-in-place-of-direct-struct-page-manipulation
+++ a/arch/mips/mm/cache.c
@@ -117,7 +117,7 @@ void __flush_dcache_pages(struct page *p
 	 * get faulted into the tlb (and thus flushed) anyways.
 	 */
 	for (i = 0; i < nr; i++) {
-		addr = (unsigned long)kmap_local_page(page + i);
+		addr = (unsigned long)kmap_local_page(nth_page(page, i));
 		flush_data_cache_page(addr);
 		kunmap_local((void *)addr);
 	}
_

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