Comment 1 for bug 1484289

I have found a bug in hdparm v9.43 with the --fibmap option.
For certain filesystems it returns incorrect values when compared with filefrag, example below for vfat. Notice the factor of 8 difference between number of extent sectors: 125092 vs 1000736.
I have reported this to Mark Lord (author) and am awaiting feedback whether this has been fixed in a later version.

hdparm --fibmap ./edisk5/mnt.erox9t4T/emptyspace.zeros, out=./edisk5/mnt.erox9t4T/emptyspace.zeros:
filesystem blocksize 512, begins at LBA 4102144; assuming 512 byte sectors.
byte_offset begin_LBA end_LBA sectors
0 4125406 4250497 125092, err=, ret=0

filefrag -b512 -e ./edisk5/mnt.erox9t4T/emptyspace.zeros, out=Filesystem type is: 4d44
File size of ./edisk5/mnt.erox9t4T/emptyspace.zeros is 512376832 (1000736 blocks of 512 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 1000735: 186096.. 1186831: 1000736: 1186824: merged,eof
./edisk5/mnt.erox9t4T/emptyspace.zeros: 1 extent found, err=, ret=0