Hello, this patches addresses problems in handling of filesystem errors in ext4. When we hit metadata error, we want to store information about the error in the superblock. Currently we do it through direct superblock modification which can lead to lost information, checksum failures, or DIF/DIX failures. Fix various races in the error handling so that the superblock update is reliable. The patches have passed xfstests for me in various configurations and some targetted manual testing of the error handling. Honza
