Miao Xie
2013-Feb-07 06:01 UTC
[PATCH 1/2] Btrfs: fix the race between bio and btrfs_stop_workers
open_ctree() need read the metadata to initialize the global information of btrfs. But it may fail after it submit some bio, and then it will jump to the error path. Unfortunately, it doesn''t check if there are some bios in flight, and just stop all the worker threads. As a result, when the submitted bios end, they can not find any worker thread which can deal with subsequent work, then oops happen. kernel BUG at fs/btrfs/async-thread.c:605! Fix this problem by invoking invalidate_inode_pages2() before we stop the worker threads. This function will wait until the bio end because it need lock the pages which are going to be invalidated, and if a page is under disk read IO, it must be locked. invalidate_inode_pages2() need wait until end bio handler to unlocked it. Reported-and-Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> --- fs/btrfs/disk-io.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 0c31d07..d8fd711 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -2728,13 +2728,13 @@ fail_cleaner: * kthreads */ filemap_write_and_wait(fs_info->btree_inode->i_mapping); - invalidate_inode_pages2(fs_info->btree_inode->i_mapping); fail_block_groups: btrfs_free_block_groups(fs_info); fail_tree_roots: free_root_pointers(fs_info, 1); + invalidate_inode_pages2(fs_info->btree_inode->i_mapping); fail_sb_buffer: btrfs_stop_workers(&fs_info->generic_worker); @@ -2755,7 +2755,6 @@ fail_alloc: fail_iput: btrfs_mapping_tree_free(&fs_info->mapping_tree); - invalidate_inode_pages2(fs_info->btree_inode->i_mapping); iput(fs_info->btree_inode); fail_bdi: bdi_destroy(&fs_info->bdi); -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html