The memory barrier smp_wmb() is needed to make sure that preceding stores to the page contents become visible before the below set_pte_at() write. Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Yin Fengwei <fengwei.yin@xxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- mm/hugetlb_vmemmap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c index 196159000897..ba2a2596fb4e 100644 --- a/mm/hugetlb_vmemmap.c +++ b/mm/hugetlb_vmemmap.c @@ -286,6 +286,11 @@ static void vmemmap_restore_pte(pte_t *pte, unsigned long addr, copy_page(to, (void *)walk->reuse_addr); reset_struct_pages(to); + /* + * Makes sure that preceding stores to the page contents become visible + * before the set_pte_at() write. + */ + smp_wmb(); set_pte_at(&init_mm, addr, pte, mk_pte(page, pgprot)); } -- 2.23.0
