[PATCH treewide 0/5] clk: Make sure clk_init_data is fully initialized (part 1)

[PATCH treewide 0/5] clk: Make sure clk_init_data is fully initialized (part 1)

[Geert Uytterhoeven]

	Hi all,

The clk_init_data structure contains three mutually-exclusive members
for different methods to specify the possible parents of a clock,
prompting drivers to initialize only the members they need.  When commit
fc0c209c147f35ed ("clk: Allow parents to be specified without string
names") added the last two methods, this was done in a
backwards-compatible way, using a priority-based scheme:
  - .name, .ops, .num_parents, and .flags must always be initialized,
  - if .num_parents is non-zero, .parent_names must be initialized,
      - if .parent_names is NULL, .parent_data must be initialized,
	  - if .parent_data is NULL, .parent_hws must be initialized
	    and valid.

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

This (small) series is part 1, and fixes all cases that I identified to
be real bugs:
  - The first patch fixes a crash I saw on BeagleBone Black,
  - The other patches are only compile-tested.
All patches in this series can be applied independently.

Part 2 will be much larger (touching 185 files), and will fix the
remaining cases that are currently harmless.

Thanks for your comments!

Geert Uytterhoeven (5):
  clk: ti: Make sure clk_init_data is fully initialized
  clk: visconti: Make sure clk_init_data is fully initialized
  hwmon: (ltc4282) Make sure clk_init_data is fully initialized
  iio: frequency: adf4377: Make sure clk_init_data is fully initialized
  spi: amlogic-spisg: Make sure clk_init_data is fully initialized

 drivers/clk/ti/adpll.c          | 4 ++--
 drivers/clk/ti/divider.c        | 2 +-
 drivers/clk/ti/mux.c            | 2 +-
 drivers/clk/visconti/clkc.c     | 2 +-
 drivers/hwmon/ltc4282.c         | 2 +-
 drivers/iio/frequency/adf4377.c | 2 +-
 drivers/spi/spi-amlogic-spisg.c | 2 +-
 7 files changed, 8 insertions(+), 8 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 treewide 1/5] clk: ti: 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.

_register_mux() fills in init.parent_data, and assumes that
init.parent_names is NULL.  However, the latter in uninitialized, and
thus may cause a crash.

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

Fixes: 667f420c09f1417c ("clk: ti: mux: resolve parent clocks by DT index, not by name")
Closes: https://lore.kernel.org/CAMuHMdU3yVqoyHC4eNF2NuYo8wy+6ODLoYat4R71X99Mxc_=kw@mail.gmail.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/clk/ti/adpll.c   | 4 ++--
 drivers/clk/ti/divider.c | 2 +-
 drivers/clk/ti/mux.c     | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/ti/adpll.c b/drivers/clk/ti/adpll.c
index e305fcbac6475b03..8885d28face50beb 100644
--- a/drivers/clk/ti/adpll.c
+++ b/drivers/clk/ti/adpll.c
@@ -483,7 +483,7 @@ static const struct clk_ops ti_adpll_ops = {
 
 static int ti_adpll_init_dco(struct ti_adpll_data *d)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	struct clk *clock;
 	const char *postfix;
 	int width, err;
@@ -576,7 +576,7 @@ static int ti_adpll_init_clkout(struct ti_adpll_data *d,
 				struct clk *clk1)
 {
 	struct ti_adpll_clkout_data *co;
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	struct clk_ops *ops;
 	const char *parent_names[2];
 	const char *child_name;
diff --git a/drivers/clk/ti/divider.c b/drivers/clk/ti/divider.c
index af923b8cb0ed8fbc..3b438c2d68aacd7c 100644
--- a/drivers/clk/ti/divider.c
+++ b/drivers/clk/ti/divider.c
@@ -311,7 +311,7 @@ static struct clk *_register_divider(struct device_node *node,
 				     u32 flags,
 				     struct clk_omap_divider *div)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	const char *parent_name;
 	const char *name;
 
diff --git a/drivers/clk/ti/mux.c b/drivers/clk/ti/mux.c
index ded4432f7528cc6e..0fef60e82107a5a5 100644
--- a/drivers/clk/ti/mux.c
+++ b/drivers/clk/ti/mux.c
@@ -124,9 +124,9 @@ static struct clk *_register_mux(struct device_node *node, const char *name,
 				 struct clk_omap_reg *reg, u8 shift, u32 mask,
 				 s8 latch, u8 clk_mux_flags, u32 *table)
 {
+	struct clk_init_data init = {};
 	struct clk_omap_mux *mux;
 	struct clk *clk;
-	struct clk_init_data init;
 
 	/* allocate the mux */
 	mux = kzalloc_obj(*mux);
-- 
2.43.0

[PATCH treewide 2/5] clk: visconti: 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.

visconti_clk_register_gate() fills in init.parent_data, and assumes that
init.parent_names is NULL.  However, the latter in uninitialized, and
thus may cause a crash.

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

Fixes: b4cbe606dc3674b2 ("clk: visconti: Add support common clock driver and reset driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/clk/visconti/clkc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/visconti/clkc.c b/drivers/clk/visconti/clkc.c
index d0b193b5d0b35f94..4018d1298880dfbb 100644
--- a/drivers/clk/visconti/clkc.c
+++ b/drivers/clk/visconti/clkc.c
@@ -81,9 +81,9 @@ static struct clk_hw *visconti_clk_register_gate(struct device *dev,
 						 u8	rs_idx,
 						 spinlock_t *lock)
 {
+	struct clk_init_data init = {};
 	struct visconti_clk_gate *gate;
 	struct clk_parent_data *pdata;
-	struct clk_init_data init;
 	struct clk_hw *hw;
 	int ret;
 
-- 
2.43.0

[PATCH treewide 3/5] hwmon: (ltc4282) 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.

ltc428_clk_provider_setup() does not fill in any parent clocks, and
assumes that init.num_parents is NULL.  However, the latter in
uninitialized, and thus may cause a crash.

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

Fixes: cbc29538dbf7d740 ("hwmon: Add driver for LTC4282")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/hwmon/ltc4282.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwmon/ltc4282.c b/drivers/hwmon/ltc4282.c
index b1675dc5b3c7fd2f..54ba4b8542e94b7b 100644
--- a/drivers/hwmon/ltc4282.c
+++ b/drivers/hwmon/ltc4282.c
@@ -1106,7 +1106,7 @@ static const struct clk_ops ltc4282_ops = {
 static int ltc428_clk_provider_setup(struct ltc4282_state *st,
 				     struct device *dev)
 {
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	int ret;
 
 	if (!IS_ENABLED(CONFIG_COMMON_CLK))
-- 
2.43.0

[PATCH treewide 4/5] iio: frequency: adf4377: 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.

adf4377_clk_register() fills in init.parent_data, and assumes that
init.parent_names is NULL.  However, the latter in uninitialized, and
thus may cause a crash.

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

Fixes: 60e5448ddbec2dc2 ("iio: frequency: adf4377: add clk provider support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/iio/frequency/adf4377.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/frequency/adf4377.c b/drivers/iio/frequency/adf4377.c
index 4dd19a9aa9943c57..f4eb9ba5878e1893 100644
--- a/drivers/iio/frequency/adf4377.c
+++ b/drivers/iio/frequency/adf4377.c
@@ -990,7 +990,7 @@ static int adf4377_clk_register(struct adf4377_state *st)
 {
 	struct spi_device *spi = st->spi;
 	struct device *dev = &spi->dev;
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	struct clk_parent_data parent_data;
 	int ret;
 
-- 
2.43.0

[PATCH treewide 5/5] spi: amlogic-spisg: 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.

aml_spisg_clk_init() fills in init.parent_data, and assumes that
init.parent_names is NULL.  However, the latter in uninitialized, and
thus may cause a crash.

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

Fixes: cef9991e04aed330 ("spi: Add Amlogic SPISG driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Compile-tested only.
---
 drivers/spi/spi-amlogic-spisg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-amlogic-spisg.c b/drivers/spi/spi-amlogic-spisg.c
index afc8af04638d3b6e..9049a87e9d0f2df6 100644
--- a/drivers/spi/spi-amlogic-spisg.c
+++ b/drivers/spi/spi-amlogic-spisg.c
@@ -636,7 +636,7 @@ static int aml_spisg_target_abort(struct spi_controller *ctlr)
 static int aml_spisg_clk_init(struct spisg_device *spisg, void __iomem *base)
 {
 	struct device *dev = &spisg->pdev->dev;
-	struct clk_init_data init;
+	struct clk_init_data init = {};
 	struct clk_divider *div;
 	struct clk_div_table *tbl;
 	char name[32];
-- 
2.43.0

Re: [PATCH treewide 3/5] hwmon: (ltc4282) Make sure clk_init_data is fully initialized

[Guenter Roeck]

On Wed, Aug 19, 2026 at 09:05:17PM +0200, 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.
> 
> ltc428_clk_provider_setup() does not fill in any parent clocks, and
> assumes that init.num_parents is NULL.  However, the latter in
> uninitialized, and thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: cbc29538dbf7d740 ("hwmon: Add driver for LTC4282")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Applied.

Thanks,
Guenter

> ---
> Compile-tested only.
> ---
>  drivers/hwmon/ltc4282.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/hwmon/ltc4282.c b/drivers/hwmon/ltc4282.c
> index b1675dc5b3c7fd2f..54ba4b8542e94b7b 100644
> --- a/drivers/hwmon/ltc4282.c
> +++ b/drivers/hwmon/ltc4282.c
> @@ -1106,7 +1106,7 @@ static const struct clk_ops ltc4282_ops = {
>  static int ltc428_clk_provider_setup(struct ltc4282_state *st,
>  				     struct device *dev)
>  {
> -	struct clk_init_data init;
> +	struct clk_init_data init = {};
>  	int ret;
>  
>  	if (!IS_ENABLED(CONFIG_COMMON_CLK))

Re: [PATCH treewide 1/5] clk: ti: Make sure clk_init_data is fully initialized

[Brian Masney]

On Wed, Aug 19, 2026 at 09:05:15PM +0200, 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.
> 
> _register_mux() fills in init.parent_data, and assumes that
> init.parent_names is NULL.  However, the latter in uninitialized, and
> thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: 667f420c09f1417c ("clk: ti: mux: resolve parent clocks by DT index, not by name")
> Closes: https://lore.kernel.org/CAMuHMdU3yVqoyHC4eNF2NuYo8wy+6ODLoYat4R71X99Mxc_=kw@mail.gmail.com
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

Re: [PATCH treewide 2/5] clk: visconti: Make sure clk_init_data is fully initialized

[Brian Masney]

On Wed, Aug 19, 2026 at 09:05:16PM +0200, 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.
> 
> visconti_clk_register_gate() fills in init.parent_data, and assumes that
> init.parent_names is NULL.  However, the latter in uninitialized, and
> thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: b4cbe606dc3674b2 ("clk: visconti: Add support common clock driver and reset driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

Re: [PATCH treewide 3/5] hwmon: (ltc4282) Make sure clk_init_data is fully initialized

[Brian Masney]

On Wed, Aug 19, 2026 at 09:05:17PM +0200, 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.
> 
> ltc428_clk_provider_setup() does not fill in any parent clocks, and
> assumes that init.num_parents is NULL.  However, the latter in
> uninitialized, and thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: cbc29538dbf7d740 ("hwmon: Add driver for LTC4282")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

Re: [PATCH treewide 4/5] iio: frequency: adf4377: Make sure clk_init_data is fully initialized

[Brian Masney]

On Wed, Aug 19, 2026 at 09:05:18PM +0200, 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.
> 
> adf4377_clk_register() fills in init.parent_data, and assumes that
> init.parent_names is NULL.  However, the latter in uninitialized, and
> thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: 60e5448ddbec2dc2 ("iio: frequency: adf4377: add clk provider support")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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

Re: [PATCH treewide 5/5] spi: amlogic-spisg: Make sure clk_init_data is fully initialized

[Brian Masney]

On Wed, Aug 19, 2026 at 09:05:19PM +0200, 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.
> 
> aml_spisg_clk_init() fills in init.parent_data, and assumes that
> init.parent_names is NULL.  However, the latter in uninitialized, and
> thus may cause a crash.
> 
> Make sure all members are fully initialized, to fix such bugs, and to
> avoid future breakage when converting drivers to a different method for
> specifying the parents.
> 
> Fixes: cef9991e04aed330 ("spi: Add Amlogic SPISG driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

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