diff options
| -rw-r--r-- | include/linux/migrate.h | 8 | ||||
| -rw-r--r-- | mm/filemap.c | 13 | ||||
| -rw-r--r-- | mm/memory.c | 3 |
3 files changed, 19 insertions, 5 deletions
diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 1f0ac122c3bf..8061efd89041 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -97,6 +97,14 @@ static inline int set_movable_ops(const struct movable_operations *ops, enum pag return -ENOSYS; } +static inline void migration_entry_wait_on_locked(swp_entry_t entry, spinlock_t *ptl) + __releases(ptl) +{ + WARN_ON_ONCE(1); + + spin_unlock(ptl); +} + #endif /* CONFIG_MIGRATION */ #ifdef CONFIG_NUMA_BALANCING diff --git a/mm/filemap.c b/mm/filemap.c index 024b71da5224..8a7f4ce69aff 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1386,14 +1386,16 @@ repeat: #ifdef CONFIG_MIGRATION /** - * migration_entry_wait_on_locked - Wait for a migration entry to be removed - * @entry: migration swap entry. + * migration_entry_wait_on_locked - Wait for a migration entry or + * device_private entry to be removed. + * @entry: migration or device_private swap entry. * @ptl: already locked ptl. This function will drop the lock. * - * Wait for a migration entry referencing the given page to be removed. This is + * Wait for a migration entry referencing the given page, or device_private + * entry referencing a dvice_private page to be unlocked. This is * equivalent to folio_put_wait_locked(folio, TASK_UNINTERRUPTIBLE) except * this can be called without taking a reference on the page. Instead this - * should be called while holding the ptl for the migration entry referencing + * should be called while holding the ptl for @entry referencing * the page. * * Returns after unlocking the ptl. @@ -1435,6 +1437,9 @@ void migration_entry_wait_on_locked(swp_entry_t entry, spinlock_t *ptl) * If a migration entry exists for the page the migration path must hold * a valid reference to the page, and it must take the ptl to remove the * migration entry. So the page is valid until the ptl is dropped. + * Similarly any path attempting to drop the last reference to a + * device-private page needs to grab the ptl to remove the device-private + * entry. */ spin_unlock(ptl); diff --git a/mm/memory.c b/mm/memory.c index 61748b762876..e43f0a4702c4 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4642,7 +4642,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) unlock_page(vmf->page); put_page(vmf->page); } else { - pte_unmap_unlock(vmf->pte, vmf->ptl); + pte_unmap(vmf->pte); + migration_entry_wait_on_locked(entry, vmf->ptl); } } else if (is_hwpoison_entry(entry)) { ret = VM_FAULT_HWPOISON; |