Re: [PATCH 02/14] kunit: bug: Count suppressed warning backtraces

Kees Cook
2024-03-12T22:02:07Z

On Tue, Mar 12, 2024 at 10:02:57AM -0700, Guenter Roeck wrote:
> Count suppressed warning backtraces to enable code which suppresses
> warning backtraces to check if the expected backtrace(s) have been
> observed.
>
> Using atomics for the backtrace count resulted in build errors on some
> architectures due to include file recursion, so use a plain integer
> for now.
>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> include/kunit/bug.h | 7 ++++++-
> lib/kunit/bug.c | 4 +++-
> 2 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/include/kunit/bug.h b/include/kunit/bug.h
> index 1e34da961599..2097a854ac8c 100644
> --- a/include/kunit/bug.h
> +++ b/include/kunit/bug.h
> @@ -20,6 +20,7 @@
> struct __suppressed_warning {
> struct list_head node;
> const char *function;
> + int counter;

Thanks for adding a counter!

> };
>
> void __start_suppress_warning(struct __suppressed_warning *warning);
> @@ -28,7 +29,7 @@ bool __is_suppressed_warning(const char *function);
>
> #define DEFINE_SUPPRESSED_WARNING(func) \
> struct __suppressed_warning __kunit_suppress_##func = \
> - { .function = __stringify(func) }
> + { .function = __stringify(func), .counter = 0 }
>
> #define START_SUPPRESSED_WARNING(func) \
> __start_suppress_warning(&__kunit_suppress_##func)
> @@ -39,12 +40,16 @@ bool __is_suppressed_warning(const char *function);
> #define IS_SUPPRESSED_WARNING(func) \
> __is_suppressed_warning(func)
>
> +#define SUPPRESSED_WARNING_COUNT(func) \
> + (__kunit_suppress_##func.counter)
> +
> #else /* CONFIG_KUNIT */
>
> #define DEFINE_SUPPRESSED_WARNING(func)
> #define START_SUPPRESSED_WARNING(func)
> #define END_SUPPRESSED_WARNING(func)
> #define IS_SUPPRESSED_WARNING(func) (false)
> +#define SUPPRESSED_WARNING_COUNT(func) (0)
>
> #endif /* CONFIG_KUNIT */
> #endif /* __ASSEMBLY__ */
> diff --git a/lib/kunit/bug.c b/lib/kunit/bug.c
> index f93544d7a9d1..13b3d896c114 100644
> --- a/lib/kunit/bug.c
> +++ b/lib/kunit/bug.c
> @@ -32,8 +32,10 @@ bool __is_suppressed_warning(const char *function)
> return false;
>
> list_for_each_entry(warning, &suppressed_warnings, node) {
> - if (!strcmp(function, warning->function))
> + if (!strcmp(function, warning->function)) {
> + warning->counter++;
> return true;
> + }
> }
> return false;
> }
> --
> 2.39.2
>

Reviewed-by: Kees Cook <keescook@chromium.org>

--
Kees Cook