[PATCH v1] clk: devres: fix cleanup in devm_clk_get_optional_enabled_with_rate()

[PATCH v1] clk: devres: fix cleanup in devm_clk_get_optional_enabled_with_rate()

[Onur Özkan]

devm_clk_get_optional_enabled_with_rate() registers its cleanup action
before setting the clock rate. If setting the rate fails, it attempts to
disable and unprepare a clock that was never enabled. This issue was
spotted while reviewing "rust: clk: add devres-managed clks" [1].

Register the cleanup action only after successfully preparing and enabling
the clock.

[1]: https://lore.kernel.org/rust-for-linux/20260706-clk-type-state-v5-3-67c5f326a16c@collabora.com

Fixes: 9934a1bd45b2 ("clk: provide devm_clk_get_optional_enabled_with_rate()")
Signed-off-by: Onur Özkan <work@onurozkan.dev>
---
 drivers/clk/clk-devres.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
index 994d5bc5168b..697d102449c1 100644
--- a/drivers/clk/clk-devres.c
+++ b/drivers/clk/clk-devres.c
@@ -99,6 +99,11 @@ struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id)
 }
 EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
 
+static void devm_clk_disable_unprepare(void *data)
+{
+	clk_disable_unprepare(data);
+}
+
 struct clk *devm_clk_get_optional_enabled_with_rate(struct device *dev,
 						    const char *id,
 						    unsigned long rate)
@@ -106,8 +111,7 @@ struct clk *devm_clk_get_optional_enabled_with_rate(struct device *dev,
 	struct clk *clk;
 	int ret;
 
-	clk = __devm_clk_get(dev, id, clk_get_optional, NULL,
-			     clk_disable_unprepare);
+	clk = devm_clk_get_optional(dev, id);
 	if (IS_ERR(clk))
 		return ERR_CAST(clk);
 
@@ -119,6 +123,10 @@ struct clk *devm_clk_get_optional_enabled_with_rate(struct device *dev,
 	if (ret)
 		goto out_put_clk;
 
+	ret = devm_add_action_or_reset(dev, devm_clk_disable_unprepare, clk);
+	if (ret)
+		goto out_put_clk;
+
 	return clk;
 
 out_put_clk:
-- 
2.51.2

Re: [PATCH v1] clk: devres: fix cleanup in devm_clk_get_optional_enabled_with_rate()

[Brian Masney]

On Sat, Aug 01, 2026 at 02:16:34PM +0300, Onur Özkan wrote:
> devm_clk_get_optional_enabled_with_rate() registers its cleanup action
> before setting the clock rate. If setting the rate fails, it attempts to
> disable and unprepare a clock that was never enabled. This issue was
> spotted while reviewing "rust: clk: add devres-managed clks" [1].
> 
> Register the cleanup action only after successfully preparing and enabling
> the clock.
> 
> [1]: https://lore.kernel.org/rust-for-linux/20260706-clk-type-state-v5-3-67c5f326a16c@collabora.com
> 
> Fixes: 9934a1bd45b2 ("clk: provide devm_clk_get_optional_enabled_with_rate()")
> Signed-off-by: Onur Özkan <work@onurozkan.dev>

Reviewed-by: Brian Masney <bmasney@redhat.com>

Re: [PATCH v1] clk: devres: fix cleanup in devm_clk_get_optional_enabled_with_rate()

[kernel test robot]

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
In-Reply-To: <20260801111637.304590-1-work@onurozkan.dev>
References: <20260801111637.304590-1-work@onurozkan.dev>
TO: "Onur Özkan" <work@onurozkan.dev>
TO: linux-clk@vger.kernel.org
TO: linux-kernel@vger.kernel.org
CC: mturquette@baylibre.com
CC: sboyd@kernel.org
CC: bmasney@redhat.com
CC: daniel.almeida@collabora.com
CC: "Onur Özkan" <work@onurozkan.dev>

Hi Onur,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linux-review/Daniel-Almeida/rust-clk-use-the-type-state-pattern/20260706-224926]

url:    https://github.com/intel-lab-lkp/linux/commits/Onur-zkan/clk-devres-fix-cleanup-in-devm_clk_get_optional_enabled_with_rate/20260805-211528
base:   https://github.com/intel-lab-lkp/linux Daniel-Almeida/rust-clk-use-the-type-state-pattern/20260706-224926
patch link:    https://lore.kernel.org/r/20260801111637.304590-1-work%40onurozkan.dev
patch subject: [PATCH v1] clk: devres: fix cleanup in devm_clk_get_optional_enabled_with_rate()
:::::: branch date: 3 days ago
:::::: commit date: 3 days ago
config: parisc-randconfig-r071-20260808 (https://download.01.org/0day-ci/archive/20260809/202608090025.dwxdfqFr-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 11.5.0
smatch: v0.5.0-9187-g5189e3fb

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202608090025.dwxdfqFr-lkp@intel.com/

smatch warnings:
drivers/clk/clk-devres.c:134 devm_clk_get_optional_enabled_with_rate() warn: 'clk' from clk_prepare_enable() not released on lines: 134.

vim +/clk +134 drivers/clk/clk-devres.c

1c34a54a924f326 Onur Özkan          2026-08-01  106  
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  107  struct clk *devm_clk_get_optional_enabled_with_rate(struct device *dev,
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  108  						    const char *id,
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  109  						    unsigned long rate)
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  110  {
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  111  	struct clk *clk;
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  112  	int ret;
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  113  
1c34a54a924f326 Onur Özkan          2026-08-01  114  	clk = devm_clk_get_optional(dev, id);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  115  	if (IS_ERR(clk))
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  116  		return ERR_CAST(clk);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  117  
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  118  	ret = clk_set_rate(clk, rate);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  119  	if (ret)
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  120  		goto out_put_clk;
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  121  
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  122  	ret = clk_prepare_enable(clk);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  123  	if (ret)
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  124  		goto out_put_clk;
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  125  
1c34a54a924f326 Onur Özkan          2026-08-01  126  	ret = devm_add_action_or_reset(dev, devm_clk_disable_unprepare, clk);
1c34a54a924f326 Onur Özkan          2026-08-01  127  	if (ret)
1c34a54a924f326 Onur Özkan          2026-08-01  128  		goto out_put_clk;
1c34a54a924f326 Onur Özkan          2026-08-01  129  
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  130  	return clk;
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  131  
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  132  out_put_clk:
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  133  	devm_clk_put(dev, clk);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05 @134  	return ERR_PTR(ret);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  135  }
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  136  EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled_with_rate);
9934a1bd45b2b03 Bartosz Golaszewski 2024-08-05  137  

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