From 7bfc76578ecf80d87d0e8641c1e7bcbbfca9d811 Mon Sep 17 00:00:00 2001 From: Wang Shilong Date: Wed, 9 Apr 2014 19:23:22 +0800 Subject: Btrfs: make sure there are not any read requests before stopping workers commit de348ee022175401e77d7662b7ca6e231a94e3fd upstream. In close_ctree(), after we have stopped all workers,there maybe still some read requests(for example readahead) to submit and this *maybe* trigger an oops that user reported before: kernel BUG at fs/btrfs/async-thread.c:619! By hacking codes, i can reproduce this problem with one cpu available. We fix this potential problem by invalidating all btree inode pages before stopping all workers. Thanks to Miao for pointing out this problem. Signed-off-by: Wang Shilong Reviewed-by: David Sterba Signed-off-by: Chris Mason Signed-off-by: Jiri Slaby --- fs/btrfs/disk-io.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 9f1d680558bb..8964b59fee92 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3622,6 +3622,11 @@ int close_ctree(struct btrfs_root *root) btrfs_free_block_groups(fs_info); + /* + * we must make sure there is not any read request to + * submit after we stopping all workers. + */ + invalidate_inode_pages2(fs_info->btree_inode->i_mapping); btrfs_stop_all_workers(fs_info); del_fs_roots(fs_info); -- cgit v1.2.3