diff options
Diffstat (limited to 'mm/huge_memory.c')
| -rw-r--r-- | mm/huge_memory.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 2a47682d1ab7..47d76d03ce30 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -3075,6 +3075,8 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, pmd_t *pmd, bool freeze, struct folio *folio) { + bool pmd_migration = is_pmd_migration_entry(*pmd); + VM_WARN_ON_ONCE(folio && !folio_test_pmd_mappable(folio)); VM_WARN_ON_ONCE(!IS_ALIGNED(address, HPAGE_PMD_SIZE)); VM_WARN_ON_ONCE(folio && !folio_test_locked(folio)); @@ -3085,9 +3087,12 @@ void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, * require a folio to check the PMD against. Otherwise, there * is a risk of replacing the wrong folio. */ - if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) || - is_pmd_migration_entry(*pmd)) { - if (folio && folio != pmd_folio(*pmd)) + if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) || pmd_migration) { + /* + * Do not apply pmd_folio() to a migration entry; and folio lock + * guarantees that it must be of the wrong folio anyway. + */ + if (folio && (pmd_migration || folio != pmd_folio(*pmd))) return; __split_huge_pmd_locked(vma, pmd, address, freeze); } |