Re: Looks like the kyua zfs tests likely are not used on aarch64 or other contexts with unsigned char

On Sep 10, 2023, at 00:31, Mark Millard <marklmi@yahoo.com> wrote:

> kyua tests that use the:
> 
> /usr/tests/sys/cddl/zfs/bin/mkfile
> 
> program like so (for example):
> 
> mkfile 500M /testpool.1861/bigfile.0
> 
> (which should be valid) end up with mkfile
> instead reporting:
> 
> Standard error:
> Usage: mkfile [-nv] <size>[e|p|t|g|m|k|b] <filename> ...
> 
> which prevent the kyua test involved from working.
> 
> Turns out this is from expecting char to be always
> signed (so a -1 vs. 255 distinction, here in an
> aarch64 context):
> 
> . . .
> (gdb) list
> 179 /* Options. */
> 180 while ((ch = getopt(argc, argv, "nv")) != -1) {
> 181 switch (ch) {
> 182 case 'n':
> 183 nofill = 1;
> 184 break;
> 185 case 'v':
> (gdb) print ch
> $16 = 255 '\377'
> (gdb) print/x -1
> $17 = 0xffffffff
> (gdb) print/x ch
> $18 = 0xff
> . . .
> 
> With the mix of unsigned and signed it ends up
> being a 0xffu != 0xffffffffu test, which is
> always true.
> 
> So the switch is reached as if a "-" prefix was
> present (that is not). Then the "option" is classified
> as invalid and the usage message is produced.
> 
> Apparently no one had noticed. That, in turn, suggests a
> lack of inspected testing on aarch64, powerpc64,
> powerpc64le, armv7, powerpc, and powerpcspe. That, in
> turn, suggests that kyua test inspection for the likes
> of aarch64 is not historically a part of the release
> process for openzfs or for operating systems that include
> openzfs.
> 

Looks like the mkfile.c traces back to a former port
sysutils/mkfile that was unfetchable as of 2019. And,
looking around, it seems the kyua zfs tests may be a
FreeBSD only thing, not adopted in openzfs.

So various implicit assumptions when I wrote the note
do not actually hold.

FreeBSD would have to do additional testing via kyua,
beyond what openzfs does for testing, to discover the
unsigned char related mis-behavior in the mkfile that
FreeBSD's kyua tests use. Only FreeBSD variants are
likely to have a similar status, not general openzfs
including operating systems.

===
Mark Millard
marklmi at yahoo.com