Commit de348ee0 authored Apr 09, 2014 by Wang Shilong Committed by Chris Mason Jun 09, 2014

Btrfs: make sure there are not any read requests before stopping workers



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 <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>

parent 59885b39

fs/btrfs/disk-io.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -3657,6 +3657,11 @@ 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);

		free_root_pointers(fs_info, 1);