create fs without csum_seed
Filesystem UUID:          6b33f586-a183-4383-921d-30da3fef2e5c
turn on csum_seed
Filesystem UUID:          6b33f586-a183-4383-921d-30da3fef2e5c
Checksum seed:            0x3ba62721
check filesystem
fsck returns 0
Filesystem UUID:          6b33f586-a183-4383-921d-30da3fef2e5c
Checksum seed:            0x3ba62721
turn off csum_seed
Filesystem UUID:          6b33f586-a183-4383-921d-30da3fef2e5c
check filesystem
fsck returns 0
Filesystem UUID:          6b33f586-a183-4383-921d-30da3fef2e5c