selftests: kselftest_harness: fix Clang warning about zero-length format

Apparently it's more legal to pass the format as NULL, than
it is to use an empty string. Clang complains about empty
formats:

./../kselftest_harness.h:1207:30: warning: format string is empty
[-Wformat-zero-length]
1207 | diagnostic ? "%s" : "", diagnostic);
| ^~
1 warning generated.

Reported-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/all/20240409224256.1581292-1-seanjc@google.com
Fixes: 378193eff339 ("selftests: kselftest_harness: let PASS / FAIL provide diagnostic")
Tested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/20240416151048.1682352-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: kselftest: Fix build failure with NOLIBC

As Mark explains ksft_min_kernel_version() can't be compiled with nolibc,
it doesn't implement uname().

Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240412123536.GA32444@redhat.com
Closes: https://lore.kernel.org/all/f0523b3a-ea08-4615-b0fb-5b504a2d39df@sirena.org.uk/

selftests: kselftest: Mark functions that unconditionally call exit() as __noreturn

After commit 6d029c25b71f ("selftests/timers/posix_timers: Reimplement
check_timer_distribution()"), clang warns:

tools/testing/selftests/timers/../kselftest.h:398:6: warning: variable 'major' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized]
398 | if (uname(&info) || sscanf(info.release, "%u.%u.", &major, &minor) != 2)
| ^~~~~~~~~~~~
tools/testing/selftests/timers/../kselftest.h:401:9: note: uninitialized use occurs here
401 | return major > min_major || (major == min_major && minor >= min_minor);
| ^~~~~
tools/testing/selftests/timers/../kselftest.h:398:6: note: remove the '||' if its condition is always false
398 | if (uname(&info) || sscanf(info.release, "%u.%u.", &major, &minor) != 2)
| ^~~~~~~~~~~~~~~
tools/testing/selftests/timers/../kselftest.h:395:20: note: initialize the variable 'major' to silence this warning
395 | unsigned int major, minor;
| ^
| = 0

This is a false positive because if uname() fails, ksft_exit_fail_msg()
will be called, which unconditionally calls exit(), a noreturn function.
However, clang does not know that ksft_exit_fail_msg() will call exit() at
the point in the pipeline that the warning is emitted because inlining has
not occurred, so it assumes control flow will resume normally after
ksft_exit_fail_msg() is called.

Make it clear to clang that all of the functions that call exit()
unconditionally in kselftest.h are noreturn transitively by marking them
explicitly with '__attribute__((__noreturn__))', which clears up the
warning above and any future warnings that may appear for the same reason.

Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
Reported-by: John Stultz <jstultz@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240411-mark-kselftest-exit-funcs-noreturn-v1-1-b027c948f586@kernel.org
Closes: https://lore.kernel.org/all/20240410232637.4135564-2-jstultz@google.com/

selftests/timers/posix_timers: Reimplement check_timer_distribution()

check_timer_distribution() runs ten threads in a busy loop and tries to
test that the kernel distributes a process posix CPU timer signal to every
thread over time.

There is not guarantee that this is true even after commit bcb7ee79029d
("posix-timers: Prefer delivery of signals to the current thread") because
that commit only avoids waking up the sleeping process leader thread, but
that has nothing to do with the actual signal delivery.

As the signal is process wide the first thread which observes sigpending
and wins the race to lock sighand will deliver the signal. Testing shows
that this hangs on a regular base because some threads never win the race.

The comment "This primarily tests that the kernel does not favour any one."
is wrong. The kernel does favour a thread which hits the timer interrupt
when CLOCK_PROCESS_CPUTIME_ID expires.

Rewrite the test so it only checks that the group leader sleeping in join()
never receives SIGALRM and the thread which burns CPU cycles receives all
signals.

In older kernels which do not have commit bcb7ee79029d ("posix-timers:
Prefer delivery of signals to the current thread") the test-case fails
immediately, the very 1st tick wakes the leader up. Otherwise it quickly
succeeds after 100 ticks.

CI testing wants to use newer selftest versions on stable kernels. In this
case the test is guaranteed to fail.

So check in the failure case whether the kernel version is less than v6.3
and skip the test result in that case.

[ tglx: Massaged change log, renamed the version check helper ]

Fixes: e797203fb3ba ("selftests/timers/posix_timers: Test delivery of signals across threads")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240409133802.GD29396@redhat.com

selftests: kselftest_harness: separate diagnostic message with # in ksft_test_result_code()

According to the spec we should always print a # if we add
a diagnostic message. Having the caller pass in the new line
as part of diagnostic message makes handling this a bit
counter-intuitive, so append the new line in the helper.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: kselftest_harness: print test name for SKIP

Jakub points out that for parsers it's rather useful to always
have the test name on the result line. Currently if we SKIP
(or soon XFAIL or XPASS), we will print:

ok 17 # SKIP SCTP doesn't support IP_BIND_ADDRESS_NO_PORT

^
no test name

Always print the test name.
KTAP format seems to allow or even call for it, per:
https://docs.kernel.org/dev-tools/ktap.html

Suggested-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/all/87jzn6lnou.fsf@cloudflare.com/
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: kselftest: add ksft_test_result_code(), handling all exit codes

For generic test harness code it's more useful to deal with exit
codes directly, rather than having to switch on them and call
the right ksft_test_result_*() helper. Add such function to kselftest.h.

Note that "directive" and "diagnostic" are what ktap docs call
those parts of the message.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests:modify the incorrect print format

when the argument type is 'unsigned int',printf '%u'
in format string. Problem found during code reading.

Update commit log with information on how the problem
was found:
Shuah Khan <skhan@linuxfoundation.org>

Signed-off-by: zhujun2 <zhujun2@cmss.chinamobile.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Add printf attribute to kselftest prints

Kselftest header defines multiple variadic functions that use printf
along with other logic.

There is no format checking for the variadic functions that use
printing inside kselftest.h. Because of this the compiler won't
be able to catch instances of mismatched printf formats and debugging
tests might be more difficult.

Add the common __printf() attribute macro to kselftest.h.

Add __printf() attribute to every function using formatted printing
with variadic arguments.

Adding the attribute and compiling all selftests exposes a number of
-Wformat warnings which were previously unnoticed due to a lack of
format specifiers checking by the compiler.

Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kselftest: Add a ksft_perror() helper

The standard library perror() function provides a convenient way to print
an error message based on the current errno but this doesn't play nicely
with KTAP output. Provide a helper which does an equivalent thing in a KTAP
compatible format.

nolibc doesn't have a strerror() and adding the table of strings required
doesn't seem like a good fit for what it's trying to do so when we're using
that only print the errno.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: line buffer test program's stdout

Patch series "selftests/mm fixes for arm64", v3.

Given my on-going work on large anon folios and contpte mappings, I
decided it would be a good idea to start running mm selftests to help
guard against regressions. However, it soon became clear that I
couldn't get the suite to run cleanly on arm64 with a vanilla v6.5-rc1
kernel (perhaps I'm just doing it wrong??), so got stuck in a rabbit
hole trying to debug and fix all the issues. Some were down to
misconfigurations, but I also found a number of issues with the tests
and even a couple of issues with the kernel.


This patch (of 8):

The selftests runner pipes the test program's stdout to tap_prefix. The
presence of the pipe means that the test program sets its stdout to be
fully buffered (as aposed to line buffered when directly connected to the
terminal). The block buffering means that there is often content in the
buffer at fork() time, which causes the output to end up duplicated. This
was causing problems for mm:cow where test results were duplicated 20-30x.

Solve this by using `stdbuf`, when available to force the test program to
use line buffered mode. This means previously printf'ed results are
flushed out of the program before any fork().

Additionally, explicitly set line buffer mode in ksft_print_header(),
which means that all test programs that use the ksft framework will
benefit even if stdbuf is not present on the system.

[ryan.roberts@arm.com: add setvbuf() to set buffering mode]
Link: https://lkml.kernel.org/r/20230726070655.2713530-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20230724082522.1202616-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20230724082522.1202616-2-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Florent Revest <revest@chromium.org>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

kselftest: Support nolibc

Rather than providing headers for inclusion which replace any offered by
the system nolibc is provided in the form of a header which should be added
to the build via the compiler command line. In order to build with nolibc
we need to not include the standard C headers, especially not stdio.h where
the definitions of stdout, stdin and stderr will actively conflict with
nolibc.

Add an include guard which suppresses the inclusion of the standard headers
when building with nolibc, allowing us to build tests using the nolibc
headers. This allows us to avoid open coding of KTAP output for
selftests that need to use nolibc in order to test interfaces that are
controlled by libc.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Provide local define of __cpuid_count()

Some selftests depend on information provided by the CPUID instruction.
To support this dependency the selftests implement private wrappers for
CPUID.

Duplication of the CPUID wrappers should be avoided.

Both gcc and clang/LLVM provide __cpuid_count() macros but neither
the macro nor its header file are available in all the compiler
versions that need to be supported by the selftests. __cpuid_count()
as provided by gcc is available starting with gcc v4.4, so it is
not available if the latest tests need to be run in all the
environments required to support kernels v4.9 and v4.14 that
have the minimal required gcc v3.2.

Duplicate gcc's __cpuid_count() macro to provide a centrally defined
macro for __cpuid_count() to help eliminate the duplicate CPUID wrappers
while continuing to compile in older environments.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: kselftest framework: provide "finished" helper

Instead of having each time that wants to use ksft_exit() have to figure
out the internals of kselftest.h, add the helper ksft_finished() that
makes sure the passes, xfails, and skips are equal to the test plan count.

Link: https://lkml.kernel.org/r/20220201013717.2464392-1-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools: fix ARRAY_SIZE defines in tools and selftests hdrs

tools/include/linux/kernel.h and kselftest_harness.h are missing
ifndef guard around ARRAY_SIZE define. Fix them to avoid duplicate
define errors during compile when another file defines it. This
problem was found when compiling selftests that include a header
with ARRAY_SIZE define.

ARRAY_SIZE is defined in several selftests. There are about 25+
duplicate defines in various selftests source and header files.
Add ARRAY_SIZE to kselftest.h in preparation for removing duplicate
ARRAY_SIZE defines from individual test files.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests/harness: Switch to TAP output

Using the kselftest_harness.h would result in non-TAP test reporting,
which didn't make much sense given that all the requirements for using
the low-level API were met. Switch to using ksft_*() helpers while
retaining as much of a human-readability as possible.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Add header documentation and helpers

Add "how to use this API" documentation to kselftest.h, and include some
addition helpers and notes to make things easier to use.

Additionally removes the incorrect "Bail out!" line from the standard exit
path. The TAP13 specification says that "Bail out!" should be used when
giving up before all tests have been run. For a "normal" execution run,
the selftests should not report "Bail out!".

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kselftest: fix TAP output for skipped tests

According to the TAP specification, a skipped test must be marked as "ok"
and annotated with the SKIP directive, for example

ok 23 # skip Insufficient flogiston pressure.
(https://testanything.org/tap-specification.html)

Fix the kselftest infrastructure to match this.

For ksft_exit_skip, it is preferrable to emit a dummy plan line that
indicates the whole test was skipped, but this is not always possible
because of ksft_exit_skip being used as a "shortcut" by the tests.
In that case, print the test counts and a normal "ok" line. The format
is now the same independent of whether msg is NULL or not (but it is
never NULL in any caller right now).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kselftest: ksft_test_num return type should be unsigned

Fixes a compiler warning:

In file included from sync_test.c:37:
../kselftest.h: In function ‘ksft_print_cnts’:
../kselftest.h:78:16: warning: comparison of integer expressions of different signedness: ‘unsigned int’ and ‘int’ [-Wsign-compare]
if (ksft_plan != ksft_test_num())
^~

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kselftest: save-and-restore errno to allow for %m formatting

Previously, using "%m" in a ksft_* format string can result in strange
output because the errno value wasn't saved before calling other libc
functions. The solution is to simply save and restore the errno before
we format the user-supplied format string.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Add test plan API to kselftest.h and adjust callers

The test plan for TAP needs to be declared immediately after the header.
This adds the test plan API to kselftest.h and updates all callers to
declare their expected test counts.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Move test output to diagnostic lines

This changes the selftest output so that each test's output is prefixed
with "# " as a TAP "diagnostic line".

This creates a bit of a kernel-specific TAP dialect where the diagnostics
precede the results. The TAP spec isn't entirely clear about this, though,
so I think it's the correct solution so as to keep interactive runs making
sense. If the output _followed_ the result line in the spec-suggested
YAML form, each test would dump all of its output at once instead of as
it went, making debugging harder.

This does, however, solve the recursive TAP output problem, as sub-tests
will simply be prefixed by "# ". Parsing sub-tests becomes a simple
problem of just removing the first two characters of a given top-level
test's diagnostic output, and parsing the results.

Note that the shell construct needed to both get an exit code from
the first command in a pipe and still filter the pipe (to add the "# "
prefix) uses a POSIX solution rather than the bash "pipefail" option
which is not supported by dash.

Since some test environments may have a very minimal set of utilities
available, the new prefixing code will fall back to doing line-at-a-time
prefixing if perl and/or stdbuf are not available.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: Add plan line and fix result line syntax

The TAP version 13 spec requires a "plan" line, which has been missing.
Since we always know how many tests we're going to run, emit the count on
the plan line. This also fixes the result lines to remove the "1.." prefix
which is against spec, and to mark skips with the correct "# SKIP" suffix.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftest: include stdio.h in kselftest.h

While playing around with a way to skip the seccomp get_metadata test, I
noticed that this header uses printf() without defining it, leading to,

../kselftest.h: In function ‘ksft_print_header’:
../kselftest.h:61:3: warning: implicit declaration of function ‘printf’ [-Wimplicit-function-declaration]
printf("TAP version 13\n");
^~~~~~
../kselftest.h:61:3: warning: incompatible implicit declaration of built-in function ‘printf’
../kselftest.h:61:3: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’

if user code doesn't also use printf.

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>

selftests: kselftest: Remove outdated comment

Commit 3c07aaef6598 ("selftests: kselftest: change KSFT_SKIP=4 instead of
KSFT_PASS") reverted commit 11867a77eb85 ("selftests: kselftest framework:
change skip exit code to 0") but missed removing the comment which that
commit added, so do that now.

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

selftests: kselftest: change KSFT_SKIP=4 instead of KSFT_PASS

KSFT_SKIP points to KSFT_PASS resulting in reporting skipped tests as
Passed, when test programs exit with KSFT_SKIP or call ksft_exit_skip().
If tests are skipped because of unmet dependencies and/or unsupported
configuration, reporting them as passed leads to too many false positives.

Fix it to return a skip code of 4 to clearly differentiate the skipped
tests.

Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>

selftests: kselftest framework: add handling for TAP header level

Introduce environment variable KSFT_TAP_LEVEL to avoid printing
nested TAP headers for each test. lib.mk run_tests target prints
TAP header before invoking the test program or test script. Tests
need a way to suppress TAP headers if it is already printed out.

This new environment variable adds a way for ksft_print_header()
print TAP header only when KSFT_TAP_LEVEL isn't set.

lib.mk run_tests and test program should print TAP header and set
KSFT_TAP_LEVEL to avoid a second TAP header to be printed.

selftests Makefile should export KSFT_TAP_LEVEL and add TAP Header
echo to the run_kselftest.sh script from emit_tests target handling.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: kselftest.h: Add SPDX license identifier

Replace GPL license statement with SPDX GPL-2.0 license identifier.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: kselftest framework: change skip exit code to 0

When a test is skipped, instead of using a special exit code of 4, treat
it as pass condition and use exit code of 0. It makes sense to treat skip
as pass since the test couldn't be run as opposed to a failed test.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: kselftest framework: add error counter

Some tests track errors in addition to test failures. Add ksft_error
counter, ksft_get_error_cnt(), and ksft_test_result_error() API to
get the counter value and print error message.

Update ksft_print_cnts(), and ksft_test_num() to include error counter.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: kselftest framework: add API to return pass/fail/* counts

Some tests print final pass/fail message based on fail count. Add
ksft_get_*_cnt() API to kselftest framework to return counts.

Update ksft_print_cnts() to print the test results summary message with
individual pass, fail, ... counters.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>

kselftest: add ksft_print_msg() function to output general information

Add a generic information output function: ksft_print_msg()

Signed-off-by: Paul Elder <paul.elder@pitt.edu>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftest: make ksft_* output functions variadic

Make the ksft_* output functions variadic to allow string formatting
directly in these functions.

Signed-off-by: Paul Elder <paul.elder@pitt.edu>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftest: make ksft_exit_skip() output a reason for skipping

Make ksft_exit_skip() input an optional message string as the reason
for skipping all the tests and outputs it prior to exiting.

Signed-off-by: Paul Elder <paul.elder@pitt.edu>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftest: add TAP13 conformant versions of ksft_* functions

Add TAP13 conformat output functions to kselftest.h.

Also add exit functions that output TAP13 exiting text, as well as
functions to keep track of testing progress.

Signed-off-by: Paul Elder <paul.elder@pitt.edu>
Signed-off-by: Alice Ferrazzi <alice.ferrazzi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftest: Add exit code defines

Define the exit codes with KSFT_PASS and similar so tests can use these
directly if they choose. Also enable harnesses and other tooling to use
the defines instead of hardcoding the return codes.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: linux-api@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests: add kselftest framework for uniform test reporting

Add kselftest framework for tests to use. This is a light
weight framework provides a set of interfaces to report test
results. Tests can use these interfaces to report pass, and
fail cases as well as when failure is due to configuration
problems such as missing modules, or when a test that is should
fail, fails as expected, and a test that should fail, passes.
The framework uses POSIX standard return codes for reporting
results to address the needs of users that want to run the kernel
selftests from their user-space test suites and want to know why a
test failed. In addition, the framework includes interfaces to use
to report test statistics on number of tests passed and failed.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>