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From:   Zi Yan <zi.yan@sent.com>
To:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        linux-mips@vger.kernel.org
Cc:     Zi Yan <ziy@nvidia.com>, Andrew Morton <akpm@linux-foundation.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        David Hildenbrand <david@redhat.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Muchun Song <muchun.song@linux.dev>,
        "Mike Rapoport (IBM)" <rppt@kernel.org>, stable@vger.kernel.org
Subject: [PATCH v3 5/5] mips: use nth_page() in place of direct struct page manipulation.
Date:   Wed, 13 Sep 2023 16:12:48 -0400
Message-Id: <20230913201248.452081-6-zi.yan@sent.com>
In-Reply-To: <20230913201248.452081-1-zi.yan@sent.com>
References: <20230913201248.452081-1-zi.yan@sent.com>
Reply-To: Zi Yan <ziy@nvidia.com>
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From: Zi Yan <ziy@nvidia.com>

__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.

Fixes: 15fa3e8e3269 ("mips: implement the new page table range API")
Cc: <stable@vger.kernel.org>
Signed-off-by: Zi Yan <ziy@nvidia.com>
---
 arch/mips/mm/cache.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 02042100e267..7f830634dbe7 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -117,7 +117,7 @@ void __flush_dcache_pages(struct page *page, unsigned i=
nt nr)
 	 * get faulted into the tlb (and thus flushed) anyways.
 	 */
 	for (i =3D 0; i < nr; i++) {
-		addr =3D (unsigned long)kmap_local_page(page + i);
+		addr =3D (unsigned long)kmap_local_page(nth_page(page, i));
 		flush_data_cache_page(addr);
 		kunmap_local((void *)addr);
 	}
--=20
2.40.1