[PATCH] mm/thp: fix call to mmu_notifier in set_pmd_migration_entry() v2

From: jglisse
Date: Fri Oct 12 2018 - 14:11:05 EST


From: JÃrÃme Glisse <jglisse@xxxxxxxxxx>

Inside set_pmd_migration_entry() we are holding page table locks and
thus we can not sleep so we can not call invalidate_range_start/end()

So remove call to mmu_notifier_invalidate_range_start/end() because
they are call inside the function calling set_pmd_migration_entry()
(see try_to_unmap_one()).

Changed since v1:
- removed call to invalidate_range() and updated commit message

Signed-off-by: JÃrÃme Glisse <jglisse@xxxxxxxxxx>
Reported-by: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Reviewed-by: Zi Yan <zi.yan@xxxxxxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: David Nellans <dnellans@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
---
mm/huge_memory.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 533f9b00147d..a5b28547e321 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2885,9 +2885,6 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
if (!(pvmw->pmd && !pvmw->pte))
return;

- mmu_notifier_invalidate_range_start(mm, address,
- address + HPAGE_PMD_SIZE);
-
flush_cache_range(vma, address, address + HPAGE_PMD_SIZE);
pmdval = *pvmw->pmd;
pmdp_invalidate(vma, address, pvmw->pmd);
@@ -2900,9 +2897,6 @@ void set_pmd_migration_entry(struct page_vma_mapped_walk *pvmw,
set_pmd_at(mm, address, pvmw->pmd, pmdswp);
page_remove_rmap(page, true);
put_page(page);
-
- mmu_notifier_invalidate_range_end(mm, address,
- address + HPAGE_PMD_SIZE);
}

void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
--
2.17.2