[PATCH 0/9] kunit: Fix printf format specifier issues in KUnit assertions

[David Gow]

KUnit has several macros which accept a log message, which can contain
printf format specifiers. Some of these (the explicit log macros)
already use the __printf() gcc attribute to ensure the format specifiers
are valid, but those which could fail the test, and hence used
__kunit_do_failed_assertion() behind the scenes, did not.

These include:
- KUNIT_EXPECT_*_MSG()
- KUNIT_ASSERT_*_MSG()
- KUNIT_FAIL()

This series adds the __printf() attribute, and fixes all of the issues
uncovered. (Or, at least, all of those I could find with an x86_64
allyesconfig, and the default KUnit config on a number of other
architectures. Please test!)

The issues in question basically take the following forms:
- int / long / long long confusion: typically a type being updated, but
  the format string not.
- Use of integer format specifiers (%d/%u/%li/etc) for types like size_t
  or pointer differences (technically ptrdiff_t), which would only work
  on some architectures.
- Use of integer format specifiers in combination with PTR_ERR(), where
  %pe would make more sense.
- Use of empty messages which, whilst technically not incorrect, are not
  useful and trigger a gcc warning.

We'd like to get these (or equivalent) in for 6.9 if possible, so please
do take a look if possible.

Thanks,
-- David

Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-kselftest/CAHk-=wgJMOquDO5f8ShH1f4rzZwzApNVCw643m5-Yj+BfsFstA@xxxxxxxxxxxxxx/

David Gow (9):
  kunit: test: Log the correct filter string in executor_test
  lib/cmdline: Fix an invalid format specifier in an assertion msg
  lib: memcpy_kunit: Fix an invalid format specifier in an assertion msg
  time: test: Fix incorrect format specifier
  rtc: test: Fix invalid format specifier.
  net: test: Fix printf format specifier in skb_segment kunit test
  drm: tests: Fix invalid printf format specifiers in KUnit tests
  drm/xe/tests: Fix printf format specifiers in xe_migrate test
  kunit: Annotate _MSG assertion variants with gnu printf specifiers

 drivers/gpu/drm/tests/drm_buddy_test.c | 14 +++++++-------
 drivers/gpu/drm/tests/drm_mm_test.c    |  6 +++---
 drivers/gpu/drm/xe/tests/xe_migrate.c  |  8 ++++----
 drivers/rtc/lib_test.c                 |  2 +-
 include/kunit/test.h                   | 12 ++++++------
 kernel/time/time_test.c                |  2 +-
 lib/cmdline_kunit.c                    |  2 +-
 lib/kunit/executor_test.c              |  2 +-
 lib/memcpy_kunit.c                     |  4 ++--
 net/core/gso_test.c                    |  2 +-
 10 files changed, 27 insertions(+), 27 deletions(-)

-- 
2.44.0.rc0.258.g7320e95886-goog