Re: [PATCH v2 01/11] perf debug: Avoid stack overflow in recursive error message

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Fri, Feb 28, 2025 at 02:22:58PM -0800, Ian Rogers wrote:
> In debug_file, pr_warning_once is called on error. As that function
> calls debug_file the function will yield a stack overflow. Switch the
> location of the call so the recursion is avoided.
> 
> Reviewed-by: Howard Chu <howardchu95@gmail.com>
> Signed-off-by: Ian Rogers <irogers@google.com>

Good to add this so that stable picks it:

Fixes: ec49230cf6dda704 ("perf debug: Expose debug file")

- Arnaldo

> ---
>  tools/perf/util/debug.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c
> index 995f6bb05b5f..f9ef7d045c92 100644
> --- a/tools/perf/util/debug.c
> +++ b/tools/perf/util/debug.c
> @@ -46,8 +46,8 @@ int debug_type_profile;
>  FILE *debug_file(void)
>  {
>  	if (!_debug_file) {
> -		pr_warning_once("debug_file not set");
>  		debug_set_file(stderr);
> +		pr_warning_once("debug_file not set");
>  	}
>  	return _debug_file;
>  }
> -- 
> 2.48.1.711.g2feabab25a-goog