2023-04-24 09:26:13

by Yuxing Liu

Subject: [PATCH 1/2] clk: imx: clk-imx8mp: use dev_ managed memory to avoid memory leak in imx8mp_clocks_probe()

Replace of_iomap() and kzalloc() with devm_of_iomap() and devm_kzalloc()
which can automatically release the related memory when the device
or driver is disassembled or unloaded to avoid potential memory leak.

In this case,iounmap(anatop_base) in line 427,433 are removed
as manual release is not required.

Fixes: 9c140d992676 ("clk: imx: Add support for i.MX8MP clock driver")
Signed-off-by: Yuxing Liu <[email protected]>
Reviewed-by: Dongliang Mu <[email protected]>
---
This issue is found by static analysis and remains untested.
---
drivers/clk/imx/clk-imx8mp.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mp.c b/drivers/clk/imx/clk-imx8mp.c
index 3253589851ff..353d58b665f9 100644
--- a/drivers/clk/imx/clk-imx8mp.c
+++ b/drivers/clk/imx/clk-imx8mp.c
@@ -416,23 +416,19 @@ static int imx8mp_clocks_probe(struct platform_device *pdev)
void __iomem *anatop_base, *ccm_base;

np = of_find_compatible_node(NULL, NULL, "fsl,imx8mp-anatop");
- anatop_base = of_iomap(np, 0);
+ anatop_base = devm_of_iomap(dev, np, 0, NULL);
of_node_put(np);
- if (WARN_ON(!anatop_base))
- return -ENOMEM;
+ if (WARN_ON(IS_ERR(anatop_base)))
+ return PTR_ERR(anatop_base);

np = dev->of_node;
ccm_base = devm_platform_ioremap_resource(pdev, 0);
- if (WARN_ON(IS_ERR(ccm_base))) {
- iounmap(anatop_base);
+ if (WARN_ON(IS_ERR(ccm_base)))
return PTR_ERR(ccm_base);
- }

- clk_hw_data = kzalloc(struct_size(clk_hw_data, hws, IMX8MP_CLK_END), GFP_KERNEL);
- if (WARN_ON(!clk_hw_data)) {
- iounmap(anatop_base);
+ clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws, IMX8MP_CLK_END), GFP_KERNEL);
+ if (WARN_ON(!clk_hw_data))
return -ENOMEM;
- }

clk_hw_data->num = IMX8MP_CLK_END;
hws = clk_hw_data->hws;
--
2.34.1

2023-04-28 08:17:35

by Peng Fan (OSS)

Subject: Re: [PATCH 1/2] clk: imx: clk-imx8mp: use dev_ managed memory to avoid memory leak in imx8mp_clocks_probe()

On 4/24/2023 5:23 PM, Yuxing Liu wrote:
> Replace of_iomap() and kzalloc() with devm_of_iomap() and devm_kzalloc()
> which can automatically release the related memory when the device
> or driver is disassembled or unloaded to avoid potential memory leak.

What do you mean "disassembled"? The i.MX8MP is an SoC which has Clock
IP built in the device.

Regards,
Peng.

>
> In this case,iounmap(anatop_base) in line 427,433 are removed
> as manual release is not required.
>
> Fixes: 9c140d992676 ("clk: imx: Add support for i.MX8MP clock driver")
> Signed-off-by: Yuxing Liu <[email protected]>
> Reviewed-by: Dongliang Mu <[email protected]>
> ---
> This issue is found by static analysis and remains untested.
> ---
> drivers/clk/imx/clk-imx8mp.c | 16 ++++++----------
> 1 file changed, 6 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/clk/imx/clk-imx8mp.c b/drivers/clk/imx/clk-imx8mp.c
> index 3253589851ff..353d58b665f9 100644
> --- a/drivers/clk/imx/clk-imx8mp.c
> +++ b/drivers/clk/imx/clk-imx8mp.c
> @@ -416,23 +416,19 @@ static int imx8mp_clocks_probe(struct platform_device *pdev)
> void __iomem *anatop_base, *ccm_base;
>
> np = of_find_compatible_node(NULL, NULL, "fsl,imx8mp-anatop");
> - anatop_base = of_iomap(np, 0);
> + anatop_base = devm_of_iomap(dev, np, 0, NULL);
> of_node_put(np);
> - if (WARN_ON(!anatop_base))
> - return -ENOMEM;
> + if (WARN_ON(IS_ERR(anatop_base)))
> + return PTR_ERR(anatop_base);
>
> np = dev->of_node;
> ccm_base = devm_platform_ioremap_resource(pdev, 0);
> - if (WARN_ON(IS_ERR(ccm_base))) {
> - iounmap(anatop_base);
> + if (WARN_ON(IS_ERR(ccm_base)))
> return PTR_ERR(ccm_base);
> - }
>
> - clk_hw_data = kzalloc(struct_size(clk_hw_data, hws, IMX8MP_CLK_END), GFP_KERNEL);
> - if (WARN_ON(!clk_hw_data)) {
> - iounmap(anatop_base);
> + clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws, IMX8MP_CLK_END), GFP_KERNEL);
> + if (WARN_ON(!clk_hw_data))
> return -ENOMEM;
> - }
>
> clk_hw_data->num = IMX8MP_CLK_END;
> hws = clk_hw_data->hws;