linux-kernel - [PATCH] firmware: cs_dsp: Remove __free() from cs_dsp_debugfs_string

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Message-ID: <20251202113425.413700-1-rf@opensource.cirrus.com>
Date: Tue,  2 Dec 2025 11:34:25 +0000
From: Richard Fitzgerald <rf@...nsource.cirrus.com>
To: broonie@...nel.org
Cc: linux-sound@...r.kernel.org, linux-kernel@...r.kernel.org,
        patches@...nsource.cirrus.com
Subject: [PATCH] firmware: cs_dsp: Remove __free() from cs_dsp_debugfs_string_read()

Don't use __free(kfree) in cs_dsp_debugfs_string_read. Instead use
normal kfree() to cleanup.

The use of __free() can create new cleanup bugs that are difficult to spot
because the defective code is idiomatically correct regular C. This
function used the suspect declaration __free(kfree) = NULL;.

The __free(kfree) didn't really do anything here. The function can be
rearranged to avoid any need to return or goto within the code.

Signed-off-by: Richard Fitzgerald <rf@...nsource.cirrus.com>
Fixes: 3045e29d248b ("firmware: cs_dsp: Append \n to debugfs string during read")
---
 drivers/firmware/cirrus/cs_dsp.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/firmware/cirrus/cs_dsp.c b/drivers/firmware/cirrus/cs_dsp.c
index c2614de47107..d35d0f5ccaf7 100644
--- a/drivers/firmware/cirrus/cs_dsp.c
+++ b/drivers/firmware/cirrus/cs_dsp.c
@@ -375,18 +375,23 @@ static ssize_t cs_dsp_debugfs_string_read(struct cs_dsp *dsp,
 					  size_t count, loff_t *ppos,
 					  const char **pstr)
 {
-	const char *str __free(kfree) = NULL;
+	const char *str;
+	ssize_t ret = 0;
 
 	scoped_guard(mutex, &dsp->pwr_lock) {
-		if (!*pstr)
-			return 0;
-
-		str = kasprintf(GFP_KERNEL, "%s\n", *pstr);
-		if (!str)
-			return -ENOMEM;
-
-		return simple_read_from_buffer(user_buf, count, ppos, str, strlen(str));
+		if (*pstr) {
+			str = kasprintf(GFP_KERNEL, "%s\n", *pstr);
+			if (str) {
+				ret = simple_read_from_buffer(user_buf, count,
+							      ppos, str, strlen(str));
+				kfree(str);
+			} else {
+				ret = -ENOMEM;
+			}
+		}
 	}
+
+	return ret;
 }
 
 static ssize_t cs_dsp_debugfs_wmfw_read(struct file *file,
-- 
2.47.3