2022-03-03 09:44:51

by Krzysztof Kozlowski

Subject: Re: [PATCH] clk/samsung: Use of_device_get_match_data()

On 03/03/2022 10:22, [email protected] wrote:
> From: Minghao Chi (CGEL ZTE) <[email protected]>
>
> Use of_device_get_match_data() to simplify the code.
>
> Reported-by: Zeal Robot <[email protected]>

Where is the bug report to be credited? Where is the actual bug which
justifies usage of "Reported-by" tag (it is *only* for crediting bug
reporters)? Last time this email was invalid - why do you add invalid
emails to commit log?

NAK.

Please resend without this.

Best regards,
Krzysztof

2022-03-04 02:48:57

by CGEL

Subject: [PATCH] clk/samsung: Use of_device_get_match_data()

From: Minghao Chi (CGEL ZTE) <[email protected]>

Use of_device_get_match_data() to simplify the code.

Signed-off-by: Minghao Chi (CGEL ZTE) <[email protected]>
---
drivers/clk/samsung/clk-exynos-clkout.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos-clkout.c b/drivers/clk/samsung/clk-exynos-clkout.c
index e6d6cbf8c4e6..feed1a347c09 100644
--- a/drivers/clk/samsung/clk-exynos-clkout.c
+++ b/drivers/clk/samsung/clk-exynos-clkout.c
@@ -81,19 +81,13 @@ MODULE_DEVICE_TABLE(of, exynos_clkout_ids);
static int exynos_clkout_match_parent_dev(struct device *dev, u32 *mux_mask)
{
const struct exynos_clkout_variant *variant;
- const struct of_device_id *match;

if (!dev->parent) {
dev_err(dev, "not instantiated from MFD\n");
return -EINVAL;
}

- match = of_match_device(exynos_clkout_ids, dev->parent);
- if (!match) {
- dev_err(dev, "cannot match parent device\n");
- return -EINVAL;
- }
- variant = match->data;
+ variant = of_device_get_match_data(dev->parent);

*mux_mask = variant->mux_mask;

--
2.25.1

2022-03-04 08:19:49

by Krzysztof Kozlowski

Subject: Re: [PATCH] clk/samsung: Use of_device_get_match_data()

On 04/03/2022 02:11, [email protected] wrote:
> From: Minghao Chi (CGEL ZTE) <[email protected]>
>
> Use of_device_get_match_data() to simplify the code.
>
> Signed-off-by: Minghao Chi (CGEL ZTE) <[email protected]>
> ---
> drivers/clk/samsung/clk-exynos-clkout.c | 8 +-------
> 1 file changed, 1 insertion(+), 7 deletions(-)
>
> diff --git a/drivers/clk/samsung/clk-exynos-clkout.c b/drivers/clk/samsung/clk-exynos-clkout.c
> index e6d6cbf8c4e6..feed1a347c09 100644
> --- a/drivers/clk/samsung/clk-exynos-clkout.c
> +++ b/drivers/clk/samsung/clk-exynos-clkout.c
> @@ -81,19 +81,13 @@ MODULE_DEVICE_TABLE(of, exynos_clkout_ids);
> static int exynos_clkout_match_parent_dev(struct device *dev, u32 *mux_mask)
> {
> const struct exynos_clkout_variant *variant;
> - const struct of_device_id *match;
>
> if (!dev->parent) {
> dev_err(dev, "not instantiated from MFD\n");
> return -EINVAL;
> }
>
> - match = of_match_device(exynos_clkout_ids, dev->parent);
> - if (!match) {
> - dev_err(dev, "cannot match parent device\n");
> - return -EINVAL;
> - }
> - variant = match->data;
> + variant = of_device_get_match_data(dev->parent);
>

What about possible NULL pointer exception? Device is being instantiated
by MFD, so the match here could be false if MFD driver is updated but
this one here not. With your change returned NULL will be dereferenced
line below.

> *mux_mask = variant->mux_mask;
>


Best regards,
Krzysztof