Hi,
On Sat, 02 May 2026 15:57:42 +0200, Martin Kaiser <[email protected]> wrote:
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -1747,7 +1746,7 @@ const char **traceprobe_expand_meta_args(int argc,
> const char *argv[],
> if (args_idx != -1) {
> /* $arg* requires BTF info */
> trace_probe_log_err(0, NOSUP_BTFARG);
> + return NULL;
Returning NULL here causes traceprobe_expand_meta_args() to treat this as
success (no expansion needed), leaving *new_argc uninitialized and passing
the unexpanded "$arg*" to subsequent argument parsing (which later fails
with a confusing error).
We should return an error here rather than NULL.
Specifically, returning ERR_PTR(-EOPNOTSUPP) is the right fix, which also
eliminates the need for the params variable.
This is a bug, introduced by commit d157d7694460 ("tracing/probes: Support
BTF field access from $retval").
Can you update to fix this bug?
Thank you,
--
Masami Hiramatsu (Google) <[email protected]>
