diff options
Diffstat (limited to 'fs/btrfs/disk-io.c')
| -rw-r--r-- | fs/btrfs/disk-io.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index b59deb2c63f4..e5aad7f535aa 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1751,6 +1751,7 @@ static int cleaner_kthread(void *arg) { struct btrfs_root *root = arg; int again; + struct btrfs_trans_handle *trans; do { again = 0; @@ -1798,6 +1799,34 @@ sleep: __set_current_state(TASK_RUNNING); } } while (!kthread_should_stop()); + + /* + * Transaction kthread is stopped before us and wakes us up. + * However we might have started a new transaction and COWed some + * tree blocks when deleting unused block groups for example. So + * make sure we commit the transaction we started to have a clean + * shutdown when evicting the btree inode - if it has dirty pages + * when we do the final iput() on it, eviction will trigger a + * writeback for it which will fail with null pointer dereferences + * since work queues and other resources were already released and + * destroyed by the time the iput/eviction/writeback is made. + */ + trans = btrfs_attach_transaction(root); + if (IS_ERR(trans)) { + if (PTR_ERR(trans) != -ENOENT) + btrfs_err(root->fs_info, + "cleaner transaction attach returned %ld", + PTR_ERR(trans)); + } else { + int ret; + + ret = btrfs_commit_transaction(trans, root); + if (ret) + btrfs_err(root->fs_info, + "cleaner open transaction commit returned %d", + ret); + } + return 0; } |