diff options
| author | Thomas Hellstrom <[email protected]> | 2019-10-04 11:04:43 +0200 |
|---|---|---|
| committer | Thomas Hellstrom <[email protected]> | 2019-11-06 13:02:25 +0100 |
| commit | ace88f1018b88167a78bafd545d30816d6e207bf (patch) | |
| tree | 52d80c8bd41e9dd0efea092bd4eeb96915f7536d | |
| parent | ea81bae46032022656d45d4a395f1bf3b96697f0 (diff) | |
mm: pagewalk: Take the pagetable lock in walk_pte_range()
Without the lock, anybody modifying a pte from within this function might
have it concurrently modified by someone else.
Cc: Matthew Wilcox <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Huang Ying <[email protected]>
Cc: Jérôme Glisse <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Signed-off-by: Thomas Hellstrom <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
| -rw-r--r-- | mm/pagewalk.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/mm/pagewalk.c b/mm/pagewalk.c index d48c2a986ea3..c5fa42cab14f 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -10,8 +10,9 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pte_t *pte; int err = 0; const struct mm_walk_ops *ops = walk->ops; + spinlock_t *ptl; - pte = pte_offset_map(pmd, addr); + pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); for (;;) { err = ops->pte_entry(pte, addr, addr + PAGE_SIZE, walk); if (err) @@ -22,7 +23,7 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, pte++; } - pte_unmap(pte); + pte_unmap_unlock(pte, ptl); return err; } |