Re: [PATCH] perf trace: Fix IS_ERR() vs NULL check bug

[Ian Rogers]

On Wed, Sep 17, 2025 at 2:54 AM Fushuai Wang <wangfushuai@xxxxxxxxx> wrote:
>
> The alloc_syscall_stats() function always returns an error pointer
> (ERR_PTR) on failure. So replace NULL check with IS_ERR() check
> after calling alloc_syscall_stats() function.
>
> Fixes: fc00897c8a3f ("perf trace: Add --summary-mode option")
> Signed-off-by: Fushuai Wang <wangfushuai@xxxxxxxxx>

Reviewed-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

> ---
>  tools/perf/builtin-trace.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
> index fe737b3ac6e6..25c41b89f8ab 100644
> --- a/tools/perf/builtin-trace.c
> +++ b/tools/perf/builtin-trace.c
> @@ -4440,7 +4440,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
>
>         if (trace->summary_mode == SUMMARY__BY_TOTAL && !trace->summary_bpf) {
>                 trace->syscall_stats = alloc_syscall_stats();
> -               if (trace->syscall_stats == NULL)
> +               if (IS_ERR(trace->syscall_stats))
>                         goto out_delete_evlist;
>         }
>
> @@ -4748,7 +4748,7 @@ static int trace__replay(struct trace *trace)
>
>         if (trace->summary_mode == SUMMARY__BY_TOTAL) {
>                 trace->syscall_stats = alloc_syscall_stats();
> -               if (trace->syscall_stats == NULL)
> +               if (IS_ERR(trace->syscall_stats))
>                         goto out;
>         }
>
> --
> 2.36.1
>