[PATCH 0/2] soc: mediatek: mtk-svs: fix device leaks on probe failure

[PATCH 0/2] soc: mediatek: mtk-svs: fix device leaks on probe failure

[Johan Hovold]

This series fixes mostly benign device leaks in case the svs driver
probe defers (or is ever unbound), but which should be fixed if only to
reduce the risk of such bugs being reproduced in places where it matter
more.

Johan


Johan Hovold (2):
  soc: mediatek: mtk-svs: fix device leaks on mt8183 probe failure
  soc: mediatek: mtk-svs: fix device leaks on mt8192 probe failure

 drivers/soc/mediatek/mtk-svs.c | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

-- 
2.49.1

[PATCH 1/2] soc: mediatek: mtk-svs: fix device leaks on mt8183 probe failure

[Johan Hovold]

Make sure to drop the references taken by of_find_device_by_node() when
looking up the thermal sensor and opp devices during probe on probe
failure (e.g. probe deferral) and on driver unbind.

Fixes: 681a02e95000 ("soc: mediatek: SVS: introduce MTK SVS engine")
Cc: Roger Lu <roger.lu@mediatek.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/soc/mediatek/mtk-svs.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/soc/mediatek/mtk-svs.c b/drivers/soc/mediatek/mtk-svs.c
index 7c349a94b45c..48804e1e5a6c 100644
--- a/drivers/soc/mediatek/mtk-svs.c
+++ b/drivers/soc/mediatek/mtk-svs.c
@@ -2165,6 +2165,13 @@ static struct device *svs_add_device_link(struct svs_platform *svsp,
 	return dev;
 }
 
+static void svs_put_device(void *_dev)
+{
+	struct device *dev = _dev;
+
+	put_device(dev);
+}
+
 static int svs_mt8192_platform_probe(struct svs_platform *svsp)
 {
 	struct device *dev;
@@ -2216,11 +2223,13 @@ static int svs_mt8183_platform_probe(struct svs_platform *svsp)
 {
 	struct device *dev;
 	u32 idx;
+	int ret;
 
 	dev = svs_add_device_link(svsp, "thermal-sensor");
 	if (IS_ERR(dev))
 		return dev_err_probe(svsp->dev, PTR_ERR(dev),
 				     "failed to get thermal device\n");
+	put_device(dev);
 
 	for (idx = 0; idx < svsp->bank_max; idx++) {
 		struct svs_bank *svsb = &svsp->banks[idx];
@@ -2230,6 +2239,7 @@ static int svs_mt8183_platform_probe(struct svs_platform *svsp)
 		case SVSB_SWID_CPU_LITTLE:
 		case SVSB_SWID_CPU_BIG:
 			svsb->opp_dev = get_cpu_device(bdata->cpu_id);
+			get_device(svsb->opp_dev);
 			break;
 		case SVSB_SWID_CCI:
 			svsb->opp_dev = svs_add_device_link(svsp, "cci");
@@ -2246,6 +2256,11 @@ static int svs_mt8183_platform_probe(struct svs_platform *svsp)
 			return dev_err_probe(svsp->dev, PTR_ERR(svsb->opp_dev),
 					     "failed to get OPP device for bank %d\n",
 					     idx);
+
+		ret = devm_add_action_or_reset(svsp->dev, svs_put_device,
+					       svsb->opp_dev);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
-- 
2.49.1

[PATCH 2/2] soc: mediatek: mtk-svs: fix device leaks on mt8192 probe failure

[Johan Hovold]

Make sure to drop the references taken by of_find_device_by_node() when
looking up the thermal sensor and opp devices during probe on probe
failure (e.g. probe deferral) and on driver unbind.

Fixes: 0bbb09b2af9d ("soc: mediatek: SVS: add mt8192 SVS GPU driver")
Cc: Roger Lu <roger.lu@mediatek.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/soc/mediatek/mtk-svs.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/soc/mediatek/mtk-svs.c b/drivers/soc/mediatek/mtk-svs.c
index 48804e1e5a6c..f45537546553 100644
--- a/drivers/soc/mediatek/mtk-svs.c
+++ b/drivers/soc/mediatek/mtk-svs.c
@@ -2176,6 +2176,7 @@ static int svs_mt8192_platform_probe(struct svs_platform *svsp)
 {
 	struct device *dev;
 	u32 idx;
+	int ret;
 
 	svsp->rst = devm_reset_control_get_optional(svsp->dev, "svs_rst");
 	if (IS_ERR(svsp->rst))
@@ -2186,6 +2187,7 @@ static int svs_mt8192_platform_probe(struct svs_platform *svsp)
 	if (IS_ERR(dev))
 		return dev_err_probe(svsp->dev, PTR_ERR(dev),
 				     "failed to get lvts device\n");
+	put_device(dev);
 
 	for (idx = 0; idx < svsp->bank_max; idx++) {
 		struct svs_bank *svsb = &svsp->banks[idx];
@@ -2195,6 +2197,7 @@ static int svs_mt8192_platform_probe(struct svs_platform *svsp)
 		case SVSB_SWID_CPU_LITTLE:
 		case SVSB_SWID_CPU_BIG:
 			svsb->opp_dev = get_cpu_device(bdata->cpu_id);
+			get_device(svsb->opp_dev);
 			break;
 		case SVSB_SWID_CCI:
 			svsb->opp_dev = svs_add_device_link(svsp, "cci");
@@ -2214,6 +2217,11 @@ static int svs_mt8192_platform_probe(struct svs_platform *svsp)
 			return dev_err_probe(svsp->dev, PTR_ERR(svsb->opp_dev),
 					     "failed to get OPP device for bank %d\n",
 					     idx);
+
+		ret = devm_add_action_or_reset(svsp->dev, svs_put_device,
+					       svsb->opp_dev);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
-- 
2.49.1

Re: [PATCH 2/2] soc: mediatek: mtk-svs: fix device leaks on mt8192 probe failure

[AngeloGioacchino Del Regno]

Il 09/09/25 11:56, Johan Hovold ha scritto:
> Make sure to drop the references taken by of_find_device_by_node() when
> looking up the thermal sensor and opp devices during probe on probe
> failure (e.g. probe deferral) and on driver unbind.
> 
> Fixes: 0bbb09b2af9d ("soc: mediatek: SVS: add mt8192 SVS GPU driver")
> Cc: Roger Lu <roger.lu@mediatek.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Re: [PATCH 1/2] soc: mediatek: mtk-svs: fix device leaks on mt8183 probe failure

[AngeloGioacchino Del Regno]

Il 09/09/25 11:56, Johan Hovold ha scritto:
> Make sure to drop the references taken by of_find_device_by_node() when
> looking up the thermal sensor and opp devices during probe on probe
> failure (e.g. probe deferral) and on driver unbind.
> 
> Fixes: 681a02e95000 ("soc: mediatek: SVS: introduce MTK SVS engine")
> Cc: Roger Lu <roger.lu@mediatek.com>
> Signed-off-by: Johan Hovold <johan@kernel.org>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Re: [PATCH 0/2] soc: mediatek: mtk-svs: fix device leaks on probe failure

[Matthias Brugger]

On 09/09/2025 11:56, Johan Hovold wrote:
> This series fixes mostly benign device leaks in case the svs driver
> probe defers (or is ever unbound), but which should be fixed if only to
> reduce the risk of such bugs being reproduced in places where it matter
> more.
> 

Series queued, thanks!

> Johan
> 
> 
> Johan Hovold (2):
>    soc: mediatek: mtk-svs: fix device leaks on mt8183 probe failure
>    soc: mediatek: mtk-svs: fix device leaks on mt8192 probe failure
> 
>   drivers/soc/mediatek/mtk-svs.c | 23 +++++++++++++++++++++++
>   1 file changed, 23 insertions(+)
>