XFS format fails on null_blk device

Issue

• XFS format fails on null_blk device

[root@host]# mkfs.xfs /dev/nullb0 
meta-data=/dev/nullb0            isize=512    agcount=4, agsize=65536 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
bad magic number
bad magic number
Metadata corruption detected at 0x55673c253c68, xfs_sb block 0x0/0x200
libxfs_writebufr: write verifer failed on xfs_sb bno 0x0/0x200
releasing dirty buffer (bulk) to free list!