diff options
| author | Hugh Dickins <[email protected]> | 2021-06-24 18:39:30 -0700 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2021-06-24 19:40:53 -0700 |
| commit | a7a69d8ba88d8dcee7ef00e91d413a4bd003a814 (patch) | |
| tree | 31e5fe7533a654e098d37c62bd508bca14dc49af | |
| parent | a9a7504d9beaf395481faa91e70e2fd08f7a3dde (diff) | |
mm/thp: another PVMW_SYNC fix in page_vma_mapped_walk()
Aha! Shouldn't that quick scan over pte_none()s make sure that it holds
ptlock in the PVMW_SYNC case? That too might have been responsible for
BUGs or WARNs in split_huge_page_to_list() or its unmap_page(), though
I've never seen any.
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/linux-mm/[email protected]/
Fixes: ace71a19cec5 ("mm: introduce page_vma_mapped_walk()")
Signed-off-by: Hugh Dickins <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Tested-by: Wang Yugui <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: Ralph Campbell <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Yang Shi <[email protected]>
Cc: Zi Yan <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
| -rw-r--r-- | mm/page_vma_mapped.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index a4e962b510c7..a4435311754b 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -276,6 +276,10 @@ next_pte: goto restart; } pvmw->pte++; + if ((pvmw->flags & PVMW_SYNC) && !pvmw->ptl) { + pvmw->ptl = pte_lockptr(mm, pvmw->pmd); + spin_lock(pvmw->ptl); + } } while (pte_none(*pvmw->pte)); if (!pvmw->ptl) { |