The patch titled
Subject: mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4
has been added to the -mm mm-unstable branch. Its filename is
mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Joao Martins <joao.m.martins@xxxxxxxxxx>
Subject: mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4
Date: Thu, 10 Nov 2022 12:12:14 +0000
add smp_wmb() to ensure page contents are visible prior to PTE write
Link: https://lkml.kernel.org/r/20221110121214.6297-1-joao.m.martins@xxxxxxxxxx
Signed-off-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hugetlb_vmemmap.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/mm/hugetlb_vmemmap.c~mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4
+++ a/mm/hugetlb_vmemmap.c
@@ -246,6 +246,13 @@ static void vmemmap_remap_pte(pte_t *pte
if (unlikely(addr == walk->reuse_addr)) {
pgprot = PAGE_KERNEL;
list_del(&walk->reuse_page->lru);
+
+ /*
+ * Makes sure that preceding stores to the page contents from
+ * vmemmap_remap_free() become visible before the set_pte_at()
+ * write.
+ */
+ smp_wmb();
}
entry = mk_pte(walk->reuse_page, pgprot);
_
Patches currently in -mm which might be from joao.m.martins@xxxxxxxxxx are
mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page.patch
mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v3.patch
mm-hugetlb_vmemmap-remap-head-page-to-newly-allocated-page-v4.patch
