common: Fix mismatched output from standard mkswap
With older util-linux(e.g. v2.17.2), running some tests(e.g.
generic/472, generic/495) got the following output:
-------------------------------------------------------
+mkswap: /mnt/xfstests/scratch/swap: warning: don't erase bootbits sectors
+ on whole disk. Use -f to force.
+mkswap: unable to relabel /mnt/xfstests/scratch/swap to system_u:object_r:swapfile_t:s0: Operation not supported
-------------------------------------------------------
1) Before commit
c1f1b30 of util-linux, standard mkswap didn't zap bootbits
sectors and printed a warning until force option(i.e. -f) was given. We
define "mkswap -f" as MKSWAP_PROG and replace all standard mkswap with
$MKSWAP_PROG.
2) With mounting default SELinux context(e.g. system_u:object_r:root_t:s0),
standard mkswap tried to reset the type of default context to swapfile_t
if it is not swapfile_t, and then it failed and returned ENOTSUP expectedly
as we don't want to create any SELinux attr on purpose. standard mkswap
ignored this relabel error by commit
d97dc0e of util-linux, but it still
reported the error before commit
d97dc0e. We try to skip the reset step
in standard mkswap by mounting swapfile context directly.
Note:
We just mount swapfile context in related tests, and keep default context
in the rest of tests.
[Eryu: make mkswap a non-mandatory requirement and add comments on
"-f" option]
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>