On Sun, 28 Sept 2025 at 12:51, Ma Ke make24@iscas.ac.cn wrote:

In exynos_get_pmu_regmap_by_phandle(), driver_find_device_by_of_node() utilizes driver_find_device_by_fwnode() which internally calls driver_find_device() to locate the matching device. driver_find_device() increments the reference count of the found device by calling get_device(), but exynos_get_pmu_regmap_by_phandle() fails to call put_device() to decrement the reference count before returning. This results in a reference count leak of the device each time exynos_get_pmu_regmap_by_phandle() is executed, which may prevent the device from being properly released and cause a memory leak.

Found by code review.

Cc: stable@vger.kernel.org Fixes: 0b7c6075022c ("soc: samsung: exynos-pmu: Add regmap support for SoCs that protect PMU regs") Signed-off-by: Ma Ke make24@iscas.ac.cn

---

drivers/soc/samsung/exynos-pmu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/samsung/exynos-pmu.c b/drivers/soc/samsung/exynos-pmu.c index a77288f49d24..ed903a2dd416 100644 --- a/drivers/soc/samsung/exynos-pmu.c +++ b/drivers/soc/samsung/exynos-pmu.c @@ -302,6 +302,7 @@ struct regmap *exynos_get_pmu_regmap_by_phandle(struct device_node *np, { struct device_node *pmu_np; struct device *dev;

•   struct regmap *regmap;
  
    if (propname)
            pmu_np = of_parse_phandle(np, propname, 0);
  

@@ -325,7 +326,10 @@ struct regmap *exynos_get_pmu_regmap_by_phandle(struct device_node *np, if (!dev) return ERR_PTR(-EPROBE_DEFER);

•   return syscon_node_to_regmap(pmu_np);
  

•   regmap = syscon_node_to_regmap(pmu_np);
  

•   put_device(regmap);
  

Are you sure this code actually compiles?

•   return regmap;
  

So is regmap valid now, if you drop the reference? I think no. I also think you should check the purpose of this function. I don't see a leak here, not at callers place. Anyway build failures are my main concern.