linux-kernel - [PATCH v3] media: dvb-core: remove redundant new_node cleanup in dvb_register

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Message-Id: <20250804083908.17557-1-tuhaowen@uniontech.com>
Date: Mon,  4 Aug 2025 16:39:08 +0800
From: tuhaowen <tuhaowen@...ontech.com>
To: mchehab@...nel.org
Cc: tuhaowen@...ontech.com,
	huangbibo@...ontech.com,
	linux-kernel@...r.kernel.org,
	linux-media@...r.kernel.org,
	wangyuli@...ontech.com
Subject: [PATCH v3] media: dvb-core: remove redundant new_node cleanup in dvb_register_device

The error handling paths in dvb_register_device repeatedly check
if (new_node) before cleanup. However, if new_node allocation fails,
the function returns immediately and does not reach these branches.
Thus, these conditionals are redundant and can be removed for code
clarity and maintainability.

Signed-off-by: tuhaowen <tuhaowen@...ontech.com>

---
Changes in v3:
- Modify the redundant logic
- Link to v2: https://lore.kernel.org/all/20250804031553.4411-1-tuhaowen@uniontech.com/
---
 drivers/media/dvb-core/dvbdev.c | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/media/dvb-core/dvbdev.c b/drivers/media/dvb-core/dvbdev.c
index 9df7c213716a..aa9b4b9c5846 100644
--- a/drivers/media/dvb-core/dvbdev.c
+++ b/drivers/media/dvb-core/dvbdev.c
@@ -534,11 +534,9 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 	minor = nums2minor(adap->num, type, id);
 #endif
 	if (minor >= MAX_DVB_MINORS) {
-		if (new_node) {
-			list_del(&new_node->list_head);
-			kfree(dvbdevfops);
-			kfree(new_node);
-		}
+		list_del(&new_node->list_head);
+		kfree(dvbdevfops);
+		kfree(new_node);
 		list_del(&dvbdev->list_head);
 		kfree(dvbdev);
 		*pdvbdev = NULL;
@@ -554,11 +552,9 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 	if (ret) {
 		pr_err("%s: dvb_register_media_device failed to create the mediagraph\n",
 		       __func__);
-		if (new_node) {
-			list_del(&new_node->list_head);
-			kfree(dvbdevfops);
-			kfree(new_node);
-		}
+		list_del(&new_node->list_head);
+		kfree(dvbdevfops);
+		kfree(new_node);
 		dvb_media_device_free(dvbdev);
 		list_del(&dvbdev->list_head);
 		kfree(dvbdev);
@@ -573,11 +569,9 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev,
 	if (IS_ERR(clsdev)) {
 		pr_err("%s: failed to create device dvb%d.%s%d (%ld)\n",
 		       __func__, adap->num, dnames[type], id, PTR_ERR(clsdev));
-		if (new_node) {
-			list_del(&new_node->list_head);
-			kfree(dvbdevfops);
-			kfree(new_node);
-		}
+		list_del(&new_node->list_head);
+		kfree(dvbdevfops);
+		kfree(new_node);
 		dvb_media_device_free(dvbdev);
 		list_del(&dvbdev->list_head);
 		kfree(dvbdev);
-- 
2.20.1