[PATCH net-next 0/3] net: Make sure clk_init_data is fully initialized

[PATCH net-next 0/3] net: Make sure clk_init_data is fully initialized

[Geert Uytterhoeven]

	Hi all,

The clk_init_data structure contains several mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need.  However,
not initializing all members may cause subtle issues, which are only
exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
enabled.

Hence this series aims to make sure all members are fully initialized,
to avoid such bugs, and to prevent future breakage when converting
drivers to a different method for specifying the parents.

Part One[1] fixed all cases that I identified to be real bugs, in
response to a crash I saw on BeagleBone Black.

This series is the networking subpart of Part Two, which fixes remaining
cases that are currently harmless.  These are still fragile, and may
cause future breakage when converting drivers to a different method for
specifying the parents.

Thanks for your comments!

[1] "[PATCH treewide 0/5] clk: Make sure clk_init_data is fully
     initialized (part 1)"
    https://lore.kernel.org/cover.1787165329.git.geert+renesas@glider.be

Geert Uytterhoeven (3):
  net: macb: Make sure clk_init_data is fully initialized
  net: mdio: mux-meson-g12a: Make sure clk_init_data is fully
    initialized
  net: phy: air_en8811h: Make sure clk_init_data is fully initialized

 drivers/net/ethernet/cadence/macb_main.c | 2 +-
 drivers/net/mdio/mdio-mux-meson-g12a.c   | 2 +-
 drivers/net/phy/air_en8811h.c            | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

-- 
2.43.0

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

[PATCH net-next 1/3] net: macb: Make sure clk_init_data is fully initialized

[Geert Uytterhoeven]

The clk_init_data structure contains several mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need.  However,
not initializing all members may cause subtle issues, which are only
exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
enabled.

Make sure all members are fully initialized, to avoid such bugs, and to
prevent future breakage when converting drivers to a different method
for specifying the parents.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/net/ethernet/cadence/macb_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 1476bce77f34d2a5..319e43098f57ed7b 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5376,7 +5376,7 @@ static int fu540_c000_clk_init(struct platform_device *pdev, struct clk **pclk,
 			       struct clk **hclk, struct clk **tx_clk,
 			       struct clk **rx_clk, struct clk **tsu_clk)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	int err = 0;
 
 	err = macb_clk_init_dflt(pdev, pclk, hclk, tx_clk, rx_clk, tsu_clk);
-- 
2.43.0

Re: [PATCH net-next 1/3] net: macb: Make sure clk_init_data is fully initialized

[Théo Lebrun]

Hello Geert,

On Fri Aug 21, 2026 at 12:07 PM CEST, Geert Uytterhoeven wrote:
> The clk_init_data structure contains several mutually-exclusive members
> for different methods to specify the possible parents of a clock,
> prompting drivers to initialize only the members they need.  However,
> not initializing all members may cause subtle issues, which are only
> exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
> enabled.
>
> Make sure all members are fully initialized, to avoid such bugs, and to
> prevent future breakage when converting drivers to a different method
> for specifying the parents.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Compile-tested only.
> ---
>  drivers/net/ethernet/cadence/macb_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 1476bce77f34d2a5..319e43098f57ed7b 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -5376,7 +5376,7 @@ static int fu540_c000_clk_init(struct platform_device *pdev, struct clk **pclk,
>  			       struct clk **hclk, struct clk **tx_clk,
>  			       struct clk **rx_clk, struct clk **tsu_clk)
>  {
> -	struct clk_init_data init;
> +	struct clk_init_data init = {};
>  	int err = 0;
>  
>  	err = macb_clk_init_dflt(pdev, pclk, hclk, tx_clk, rx_clk, tsu_clk);

Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>

I cannot give you a Tested-by because this triggers only on
sifive,fu540-c000-gem compatible matching upstream devicetrees
sifive/hifive-{unleashed,unmatched}-a00.dts

Thanks,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

[PATCH net-next 2/3] net: mdio: mux-meson-g12a: Make sure clk_init_data is fully initialized

[Geert Uytterhoeven]

The clk_init_data structure contains several mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need.  However,
not initializing all members may cause subtle issues, which are only
exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
enabled.

Make sure all members are fully initialized, to avoid such bugs, and to
prevent future breakage when converting drivers to a different method
for specifying the parents.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/net/mdio/mdio-mux-meson-g12a.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/mdio/mdio-mux-meson-g12a.c b/drivers/net/mdio/mdio-mux-meson-g12a.c
index 08d6a6c93fb8bf02..e6c9ef3641afa27e 100644
--- a/drivers/net/mdio/mdio-mux-meson-g12a.c
+++ b/drivers/net/mdio/mdio-mux-meson-g12a.c
@@ -223,7 +223,7 @@ static int g12a_ephy_glue_clk_register(struct device *dev)
 {
 	struct g12a_mdio_mux *priv = dev_get_drvdata(dev);
 	const char *parent_names[PLL_MUX_NUM_PARENT];
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	struct g12a_ephy_pll *pll;
 	struct clk_mux *mux;
 	struct clk *clk;
-- 
2.43.0

[PATCH net-next 3/3] net: phy: air_en8811h: Make sure clk_init_data is fully initialized

[Geert Uytterhoeven]

The clk_init_data structure contains several mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need.  However,
not initializing all members may cause subtle issues, which are only
exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
enabled.

Make sure all members are fully initialized, to avoid such bugs, and to
prevent future breakage when converting drivers to a different method
for specifying the parents.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/net/phy/air_en8811h.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/air_en8811h.c b/drivers/net/phy/air_en8811h.c
index edd49c193e476838..d1ab8744288bba0c 100644
--- a/drivers/net/phy/air_en8811h.c
+++ b/drivers/net/phy/air_en8811h.c
@@ -932,7 +932,7 @@ static const struct clk_ops an8811hb_clk_ops = {
 
 static int an8811hb_clk_provider_setup(struct device *dev, struct clk_hw *hw)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	int ret;
 
 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
@@ -1031,7 +1031,7 @@ static const struct clk_ops en8811h_clk_ops = {
 
 static int en8811h_clk_provider_setup(struct device *dev, struct clk_hw *hw)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	int ret;
 
 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
-- 
2.43.0

Re: [PATCH net-next 0/3] net: Make sure clk_init_data is fully initialized

[Jakub Kicinski]

On Fri, 21 Aug 2026 12:07:29 +0200 Geert Uytterhoeven wrote:
>  drivers/net/ethernet/cadence/macb_main.c | 2 +-
>  drivers/net/mdio/mdio-mux-meson-g12a.c   | 2 +-
>  drivers/net/phy/air_en8811h.c            | 4 ++--

Hi Geert!

Unfortunately we don't queue -next patches during the merge window,
you'll have to repsot.
-- 
pw-bot: defer

Re: [PATCH net-next 0/3] net: Make sure clk_init_data is fully initialized

[Brian Masney]

On Fri, Aug 21, 2026 at 12:07:29PM +0200, Geert Uytterhoeven wrote:
> 	Hi all,
> 
> The clk_init_data structure contains several mutually-exclusive members
> for different methods to specify the possible parents of a clock,
> prompting drivers to initialize only the members they need.  However,
> not initializing all members may cause subtle issues, which are only
> exposed when CONFIG_INIT_STACK_ALL_PATTERN or CONFIG_INIT_STACK_NONE is
> enabled.
> 
> Hence this series aims to make sure all members are fully initialized,
> to avoid such bugs, and to prevent future breakage when converting
> drivers to a different method for specifying the parents.
> 
> Part One[1] fixed all cases that I identified to be real bugs, in
> response to a crash I saw on BeagleBone Black.
> 
> This series is the networking subpart of Part Two, which fixes remaining
> cases that are currently harmless.  These are still fragile, and may
> cause future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Thanks for your comments!
> 
> [1] "[PATCH treewide 0/5] clk: Make sure clk_init_data is fully
>      initialized (part 1)"
>     https://lore.kernel.org/cover.1787165329.git.geert+renesas@glider.be

For the series:

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