diff -urNp coreutils-8.22-orig/tests/dd/sparse.sh coreutils-8.22/tests/dd/sparse.sh --- coreutils-8.22-orig/tests/dd/sparse.sh 2013-12-04 06:48:30.000000000 -0800 +++ coreutils-8.22/tests/dd/sparse.sh 2014-04-12 17:48:22.301975386 -0700 @@ -61,8 +61,15 @@ if test $(kb_alloc file.in) -gt 3000; th dd if=file.in of=file.out bs=2M conv=sparse test 2500 -lt $(kb_alloc file.out) || fail=1 + # Note we recreate a sparse file first to avoid + # speculative preallocation seen in XFS, where a write() that + # extends a file can preallocate some extra space that + # a subsequent seek will not convert to a hole. + rm -f file.out + truncate --size=3M file.out + # Ensure that this 1MiB string of NULs *is* converted to a hole. - dd if=file.in of=file.out bs=1M conv=sparse + dd if=file.in of=file.out bs=1M conv=sparse,notrunc test $(kb_alloc file.out) -lt 2500 || fail=1 fi