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

From: Shuah Khan
Date: Tue Feb 27 2024 - 18:33:27 EST


On 2/21/24 02:27, David Gow wrote:
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


Applied all patches in this series except to linux-ksefltest kunit
for linux 6.9-rc1

drm: tests: Fix invalid printf format specifiers in KUnit tests

David, as requtested in 7/9 thread, if you can send me patch on
top pf 6.8-rc6, will apply it

7-9 drm: tests: Fix invalid printf format specifiers in KUnit tests

thanks,
-- Shuah