linux-kernel - [PATCH] rtc: amlogic-a4: fix double free caused by devm

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Message-ID: <20251020150956.491-1-vulab@iscas.ac.cn>
Date: Mon, 20 Oct 2025 23:09:56 +0800
From: Haotian Zhang <vulab@...as.ac.cn>
To: Yiting Deng <yiting.deng@...ogic.com>,
	Xianwei Zhao <xianwei.zhao@...ogic.com>,
	Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc: linux-amlogic@...ts.infradead.org,
	linux-rtc@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	stable@...r.kernel.org,
	Haotian Zhang <vulab@...as.ac.cn>
Subject: [PATCH] rtc: amlogic-a4: fix double free caused by devm

The clock obtained via devm_clk_get_enabled() is automatically managed
by devres and will be disabled and freed on driver detach. Manually
calling clk_disable_unprepare() in error path and remove function
causes double free.

Remove the redundant clk_disable_unprepare() calls from the probe
error path and aml_rtc_remove(), allowing the devm framework to
automatically manage the clock lifecycle.

Fixes: c89ac9182ee2 ("rtc: support for the Amlogic on-chip RTC")
Signed-off-by: Haotian Zhang <vulab@...as.ac.cn>
---
 drivers/rtc/rtc-amlogic-a4.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/rtc/rtc-amlogic-a4.c b/drivers/rtc/rtc-amlogic-a4.c
index 1928b29c1045..ed36b649c057 100644
--- a/drivers/rtc/rtc-amlogic-a4.c
+++ b/drivers/rtc/rtc-amlogic-a4.c
@@ -390,7 +390,6 @@ static int aml_rtc_probe(struct platform_device *pdev)
 
 	return 0;
 err_clk:
-	clk_disable_unprepare(rtc->sys_clk);
 	device_init_wakeup(dev, false);
 
 	return ret;
@@ -425,7 +424,6 @@ static void aml_rtc_remove(struct platform_device *pdev)
 {
 	struct aml_rtc_data *rtc = dev_get_drvdata(&pdev->dev);
 
-	clk_disable_unprepare(rtc->sys_clk);
 	device_init_wakeup(&pdev->dev, false);
 }
 
-- 
2.25.1