On Tue, 15 Jul 2025 20:19:44 -0700 Nathan Chancellor nathan@kernel.org wrote:

After a recent change in clang to strengthen uninitialized warnings [1], it points out that in one of the error paths in parse_btf_arg(), params is used uninitialized:

kernel/trace/trace_probe.c:660:19: warning: variable 'params' is uninitialized when used here [-Wuninitialized] 660 | return PTR_ERR(params); | ^~~~~~

Match many other NO_BTF_ENTRY error cases and return -ENOENT, clearing up the warning.

Good catch! let me pick this up.

Thank you,

Cc: stable@vger.kernel.org Closes: https://github.com/ClangBuiltLinux/linux/issues/2110 Fixes: d157d7694460 ("tracing/probes: Support BTF field access from $retval") Link: https://github.com/llvm/llvm-project/commit/2464313eef01c5b1edf0eccf57a32cde... [1] Signed-off-by: Nathan Chancellor nathan@kernel.org

---

kernel/trace/trace_probe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 424751cdf31f..40830a3ecd96 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -657,7 +657,7 @@ static int parse_btf_arg(char *varname, ret = query_btf_context(ctx); if (ret < 0 || ctx->nr_params == 0) { trace_probe_log_err(ctx->offset, NO_BTF_ENTRY);

• 	return PTR_ERR(params);
  

• 	return -ENOENT;
  

  } } params = ctx->params;

---

base-commit: 6921d1e07cb5eddec830801087b419194fde0803 change-id: 20250715-trace_probe-fix-const-uninit-warning-7dc3accce903

Best regards,

Nathan Chancellor nathan@kernel.org