On Tue, 10 Mar 2026 10:07:50 -0400
Steven Rostedt [off-list ref] wrote:

On Tue, 10 Mar 2026 12:48:41 +0100
Philipp Hahn [off-list ref] wrote:

quoted

Prefer using IS_ERR_OR_NULL() over using IS_ERR() and a manual NULL
check.

Why?

quoted

Change generated with coccinelle.

To: Steven Rostedt <rostedt@goodmis.org>
To: Masami Hiramatsu <mhiramat@kernel.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Philipp Hahn <redacted>
---
 kernel/trace/fprobe.c                | 2 +-
 kernel/trace/kprobe_event_gen_test.c | 2 +-
 kernel/trace/trace_events_hist.c     | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index dcadf1d23b8a31f571392d0c49cbd22df1716b4f..a94ce810d83b90f55d1178a9bd29c78fd068df4c 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c

@@ -607,7 +607,7 @@ static int fprobe_module_callback(struct notifier_block *nb,
 	do {
 		rhashtable_walk_start(&iter);
 
-		while ((node = rhashtable_walk_next(&iter)) && !IS_ERR(node))
+		while (!IS_ERR_OR_NULL((node = rhashtable_walk_next(&iter))))

Ug, No!

That looks so much worse than the original.

Hmm, now IS_ERR_OR_NULL() is an inline function, so it is safe.
But if you want to use IS_ERR_OR_NULL() here, it will be better something like

node = rhashtable_walk_next(&iter);
while (!IS_ERR_OR_NULL(node)) {
	fprobe_remove_node_in_module(mod, node, &alist);
	node = rhashtable_walk_next(&iter);
}

Thanks,

-- Steve

quoted

 			fprobe_remove_node_in_module(mod, node, &alist);
 
 		rhashtable_walk_stop(&iter);

diff --git a/kernel/trace/kprobe_event_gen_test.c b/kernel/trace/kprobe_event_gen_test.c
index 5a4b722b50451bfdee42769a6d3be39c055690d1..a1735ca273f0b756aa1fcfcdab30ddad9bc51c5f 100644
--- a/kernel/trace/kprobe_event_gen_test.c
+++ b/kernel/trace/kprobe_event_gen_test.c

@@ -75,7 +75,7 @@ static struct trace_event_file *gen_kretprobe_test;
 
 static bool trace_event_file_is_valid(struct trace_event_file *input)
 {
-	return input && !IS_ERR(input);
+	return !IS_ERR_OR_NULL(input);
 }
 
 /*

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 73ea180cad555898693e92ee397a1c9493c7c167..59df215e1dfd9349eca1c0823ed709ec7285f766 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c

@@ -3973,7 +3973,7 @@ trace_action_create_field_var(struct hist_trigger_data *hist_data,
 	 */
 	field_var = create_target_field_var(hist_data, system, event, var);
 
-	if (field_var && !IS_ERR(field_var)) {
+	if (!IS_ERR_OR_NULL(field_var)) {
 		save_field_var(hist_data, field_var);
 		hist_field = field_var->var;
 	} else {

-- 
Masami Hiramatsu (Google) [off-list ref]