Review of the systemtap examples testsuite results x86 Fedora rawhide

[William Cohen <wcohen at redhat dot com>]

Now that systemtap is working with 5.0.0-rcx kernel took the time to run the
systemtap examples to see what failed.

The following two tests are failing because "vitural memory exhausted"
Both are using --all-modules. There are some other test other PASS:
but it looks like they result in smaller stap-symbols.h files.  These
particular tests look to be because stap-symbols.h files are huge,
over 70MB.  This fail might be more of a result of the guest VM having
2GB of RAM. However, not sure why there is such variations in the
in the size of the stap-symbols.h files

FAIL: systemtap.examples/profiling/fileline-profile run
FAIL: systemtap.examples/profiling/periodic build


Kernel commit 23c9deeb328 eliminates all the FAN_ALL_* defines causing
FAN_ALL_CLASS_BITS to be undefined. This commit is also in the 4.20
kernels, so the errsnoop and strace examples will also break on Fedora
29/28.  _fanotify_init_flags_str function in
tapset/linux/aux_syscalls.stp will need to be fixed up.

FAIL: systemtap.examples/process/errsnoop build
FAIL: systemtap.examples/process/strace build


The following two tests seem to be having issues with the
kernel.statement() on do_sys_open being used for them.  Both get
"inconsistent relocation address".

FAIL: systemtap.examples/general/varwatch build
FAIL: systemtap.examples/general/whythefail build


The following test appears not to go down some other function other
than the vfs_* functions being currently monitored.  This does work on
RHEL7.  Looking through the list of EXPORT_SYMBOLS(vfs_*) in
linux/fs/namei.c it looks like vfs_tmpfile or vfs_mkobj are likely
missing probes:

FAIL: systemtap.examples/general/badname run


The syscall.ptrace probe point is now using the nodwarf version, so
$request target variable isn't available

FAIL: systemtap.examples/process/noptrace build


Lots of kernel internal ABI changes making the following fail to build:

FAIL: systemtap.examples/process/pfiles build

-Will