Hi, Recently I'm working on refactor btrfs raid56 (with long term objective to add proper journal to solve write-hole), and the coverage of current fstests for btrfs RAID56 is not that ideal. Is there any project testing dm/md RAID456 for things like re-silvering/write-hole problems? And how you dm guys do the tests for stacked RAID456? I really hope to learn some tricks from the existing, tried-and-true RAID456 implementations, and hopefully to solve the known write-hole bugs in btrfs. Thanks, Qu
