From 5436d6556937de6236ffa1829550d13702569dab Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 11 Apr 2023 16:25:11 +0200 Subject: [PATCH] mm/huge_memory: revert "Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"" This reverts commit 624a2c94f5b7 ("Partly revert "mm/thp: carry over dirty bit when thp splits on pmd"") and the fixup in commit e833bc503405 ("mm/thp: re-apply mkdirty for small pages after split"). Now that sparc64 mkdirty handling is fixed and no longer sets a PTE/PMD writable that shouldn't be writable, let's revert the temporary fix and remove the stale comment. The mkdirty mm selftest still passes with this change on sparc64. Note that loongarch handling was fixed in commit bf2f34a506e6 ("LoongArch: Set _PAGE_DIRTY only if _PAGE_WRITE is set in {pmd,pte}_mkdirty()") Link: https://lkml.kernel.org/r/20230411142512.438404-6-david@redhat.com Signed-off-by: David Hildenbrand Cc: Anshuman Khandual Cc: David S. Miller Cc: Hugh Dickins Cc: Peter Xu Cc: Sam Ravnborg Cc: Shuah Khan Cc: Yu Zhao Signed-off-by: Andrew Morton --- mm/huge_memory.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 00a7a98..5700b1c7 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2236,18 +2236,13 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, entry = maybe_mkwrite(entry, vma); if (anon_exclusive) SetPageAnonExclusive(page + i); + if (!write) + entry = pte_wrprotect(entry); if (!young) entry = pte_mkold(entry); /* NOTE: this may set soft-dirty too on some archs */ if (dirty) entry = pte_mkdirty(entry); - /* - * NOTE: this needs to happen after pte_mkdirty, - * because some archs (sparc64, loongarch) could - * set hw write bit when mkdirty. - */ - if (!write) - entry = pte_wrprotect(entry); if (soft_dirty) entry = pte_mksoft_dirty(entry); if (uffd_wp) -- 2.7.4