debugfs edit extended attributes
mke2fs -Fq -b 1024 test.img 512
Exit status is 0
ea_set / user.joe smith
Exit status is 0
ea_set / user.moo FEE_FIE_FOE_FUMMMMMM
Exit status is 0
ea_list /
Extended attributes:
  user.joe = "smith" (5)
  user.moo = "FEE_FIE_FOE_FUMMMMMM" (20)
Exit status is 0
ea_get / user.moo
FEE_FIE_FOE_FUMMMMMM
Exit status is 0
ea_get / nosuchea
ea_get: Extended attribute key not found while getting extended attribute
Exit status is 0
ea_rm / user.moo
Exit status is 0
ea_rm / nosuchea
Exit status is 0
ea_list /
Extended attributes:
  user.joe = "smith" (5)
Exit status is 0
ea_get / user.moo
ea_get: Extended attribute key not found while getting extended attribute
Exit status is 0
ea_rm / user.joe
Exit status is 0
ea_list /
Exit status is 0
ea_set -f d_xattr_edits.tmp / user.file_based_xattr
Exit status is 0
ea_list /
Extended attributes:
  user.file_based_xattr = "12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567\012" (108)
Exit status is 0
ea_get -f d_xattr_edits.ver.tmp / user.file_based_xattr
Exit status is 0
Compare big attribute
e2fsck -yf -N test_filesys
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
test_filesys: 11/64 files (0.0% non-contiguous), 29/512 blocks
Exit status is 0