[PATCH v3 0/4] clk drivers: Terminate clk_div_table with sentinel element

[PATCH v3 0/4] clk drivers: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

I noticed that some of the clk_div_tables in different drivers are not
terminated with a sentinel element. This may cause the code in
clk-divider.c to read garbage that happens to be beyond the end.

This patchset fixed all instances of this bug that I could find, except
for a case in drivers/phy/ti/phy-j721e-wiz.c that is already fixed in
linux-next:
  https://lore.kernel.org/lkml/20220117110108.4117-1-kishon@ti.com/

v3:
- Change the Actions patch according to Mani's comment

v2:
- Add Fixes tags

Jonathan Neuschäfer (4):
  clk: actions: Terminate clk_div_table with sentinel element
  clk: loongson1: Terminate clk_div_table with sentinel element
  clk: hisilicon: Terminate clk_div_table with sentinel element
  clk: clps711x: Terminate clk_div_table with sentinel element

 drivers/clk/actions/owl-s700.c         | 1 +
 drivers/clk/actions/owl-s900.c         | 2 +-
 drivers/clk/clk-clps711x.c             | 2 ++
 drivers/clk/hisilicon/clk-hi3559a.c    | 4 ++--
 drivers/clk/loongson1/clk-loongson1c.c | 1 +
 5 files changed, 7 insertions(+), 3 deletions(-)

--
2.34.1

[PATCH v3 1/4] clk: actions: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

In order that the end of a clk_div_table can be detected, it must be
terminated with a sentinel element (.div = 0).

In owl-s900.s, the { 0, 8 } element was probably meant to be just that,
so this patch changes { 0, 8 } to { 0, 0 }.

Fixes: d47317ca4ade1 ("clk: actions: Add S700 SoC clock support")
Fixes: d85d20053e195 ("clk: actions: Add S900 SoC clock support")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
---

v3:
- Interpret { 0, 8 } as a typo of { 0, 0 }, the sentinel element
- Add R-b tag

v2:
- Add Fixes tags
---
 drivers/clk/actions/owl-s700.c | 1 +
 drivers/clk/actions/owl-s900.c | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/actions/owl-s700.c b/drivers/clk/actions/owl-s700.c
index a2f34d13fb543..617174644f728 100644
--- a/drivers/clk/actions/owl-s700.c
+++ b/drivers/clk/actions/owl-s700.c
@@ -162,6 +162,7 @@ static struct clk_div_table hdmia_div_table[] = {

 static struct clk_div_table rmii_div_table[] = {
 	{0, 4},   {1, 10},
+	{0, 0},
 };

 /* divider clocks */
diff --git a/drivers/clk/actions/owl-s900.c b/drivers/clk/actions/owl-s900.c
index 790890978424a..63c4097c07ac7 100644
--- a/drivers/clk/actions/owl-s900.c
+++ b/drivers/clk/actions/owl-s900.c
@@ -140,7 +140,7 @@ static struct clk_div_table rmii_ref_div_table[] = {

 static struct clk_div_table usb3_mac_div_table[] = {
 	{ 1, 2 }, { 2, 3 }, { 3, 4 },
-	{ 0, 8 },
+	{ 0, 0 },
 };

 static struct clk_div_table i2s_div_table[] = {
--
2.34.1

Re: [PATCH v3 1/4] clk: actions: Terminate clk_div_table with sentinel element

[Philippe Mathieu-Daudé]

On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> In order that the end of a clk_div_table can be detected, it must be
> terminated with a sentinel element (.div = 0).
> 
> In owl-s900.s, the { 0, 8 } element was probably meant to be just that,
> so this patch changes { 0, 8 } to { 0, 0 }.
> 
> Fixes: d47317ca4ade1 ("clk: actions: Add S700 SoC clock support")
> Fixes: d85d20053e195 ("clk: actions: Add S900 SoC clock support")
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
> ---
> 
> v3:
> - Interpret { 0, 8 } as a typo of { 0, 0 }, the sentinel element
> - Add R-b tag
> 
> v2:
> - Add Fixes tags
> ---
>   drivers/clk/actions/owl-s700.c | 1 +
>   drivers/clk/actions/owl-s900.c | 2 +-
>   2 files changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/actions/owl-s700.c b/drivers/clk/actions/owl-s700.c
> index a2f34d13fb543..617174644f728 100644
> --- a/drivers/clk/actions/owl-s700.c
> +++ b/drivers/clk/actions/owl-s700.c
> @@ -162,6 +162,7 @@ static struct clk_div_table hdmia_div_table[] = {
> 
>   static struct clk_div_table rmii_div_table[] = {
>   	{0, 4},   {1, 10},
> +	{0, 0},

Again, clearer to use:

         { /* sentinel */ }

(without the trailing comma, to enforce this is the last entry).

>   };
> 
>   /* divider clocks */
> diff --git a/drivers/clk/actions/owl-s900.c b/drivers/clk/actions/owl-s900.c
> index 790890978424a..63c4097c07ac7 100644
> --- a/drivers/clk/actions/owl-s900.c
> +++ b/drivers/clk/actions/owl-s900.c
> @@ -140,7 +140,7 @@ static struct clk_div_table rmii_ref_div_table[] = {
> 
>   static struct clk_div_table usb3_mac_div_table[] = {
>   	{ 1, 2 }, { 2, 3 }, { 3, 4 },
> -	{ 0, 8 },
> +	{ 0, 0 },
>   };
> 
>   static struct clk_div_table i2s_div_table[] = {
> --
> 2.34.1
> 

Re: [PATCH v3 1/4] clk: actions: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

[-- Attachment #1: Type: text/plain, Size: 1333 bytes --]

On Sat, Feb 05, 2022 at 01:15:46PM +0100, Philippe Mathieu-Daudé wrote:
> On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> > In order that the end of a clk_div_table can be detected, it must be
> > terminated with a sentinel element (.div = 0).
> > 
> > In owl-s900.s, the { 0, 8 } element was probably meant to be just that,
> > so this patch changes { 0, 8 } to { 0, 0 }.
> > 
> > Fixes: d47317ca4ade1 ("clk: actions: Add S700 SoC clock support")
> > Fixes: d85d20053e195 ("clk: actions: Add S900 SoC clock support")
> > Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> > Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
> > ---
[...]
> >   static struct clk_div_table rmii_div_table[] = {
> >   	{0, 4},   {1, 10},
> > +	{0, 0},
> 
> Again, clearer to use:
> 
>         { /* sentinel */ }
> 
> (without the trailing comma, to enforce this is the last entry).

This style is locally consistent in the file, so anyone who reads the
file will encounter { 0, 0 } elements anyway.

So, I think it makes sense to:

- Keep this patch as is (except for the trailing comma, I'll remove that)
- Add a second patch that replaces all the sentinel elements with
  { /* sentinel */ }

This patch can go into stable branches, and the style cleanup doesn't
have to.


Best regards,
Jonathan

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[PATCH v3 2/4] clk: loongson1: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

In order that the end of a clk_div_table can be detected, it must be
terminated with a sentinel element (.div = 0).

Fixes: b4626a7f4892 ("CLK: Add Loongson1C clock support")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---

v3:
- no changes

v2:
- Add Fixes and R-b tags
---
 drivers/clk/loongson1/clk-loongson1c.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clk/loongson1/clk-loongson1c.c b/drivers/clk/loongson1/clk-loongson1c.c
index 703f87622cf5f..a6f9f20fc8b99 100644
--- a/drivers/clk/loongson1/clk-loongson1c.c
+++ b/drivers/clk/loongson1/clk-loongson1c.c
@@ -37,6 +37,7 @@ static const struct clk_div_table ahb_div_table[] = {
 	[1] = { .val = 1, .div = 4 },
 	[2] = { .val = 2, .div = 3 },
 	[3] = { .val = 3, .div = 3 },
+	[4] = { /* sentinel */ },
 };

 void __init ls1x_clk_init(void)
--
2.34.1

Re: [PATCH v3 2/4] clk: loongson1: Terminate clk_div_table with sentinel element

[Philippe Mathieu-Daudé]

On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> In order that the end of a clk_div_table can be detected, it must be
> terminated with a sentinel element (.div = 0).
> 
> Fixes: b4626a7f4892 ("CLK: Add Loongson1C clock support")
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
> 
> v3:
> - no changes
> 
> v2:
> - Add Fixes and R-b tags
> ---
>   drivers/clk/loongson1/clk-loongson1c.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/clk/loongson1/clk-loongson1c.c b/drivers/clk/loongson1/clk-loongson1c.c
> index 703f87622cf5f..a6f9f20fc8b99 100644
> --- a/drivers/clk/loongson1/clk-loongson1c.c
> +++ b/drivers/clk/loongson1/clk-loongson1c.c
> @@ -37,6 +37,7 @@ static const struct clk_div_table ahb_div_table[] = {
>   	[1] = { .val = 1, .div = 4 },
>   	[2] = { .val = 2, .div = 3 },
>   	[3] = { .val = 3, .div = 3 },
> +	[4] = { /* sentinel */ },

Sorry for being nitpicky here, but we don't need the trailing comma,
since this is the last entry.

>   };
> 
>   void __init ls1x_clk_init(void)
> --
> 2.34.1
> 

Re: [PATCH v3 2/4] clk: loongson1: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

[-- Attachment #1: Type: text/plain, Size: 1248 bytes --]

On Sat, Feb 05, 2022 at 01:17:10PM +0100, Philippe Mathieu-Daudé wrote:
> On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> > In order that the end of a clk_div_table can be detected, it must be
> > terminated with a sentinel element (.div = 0).
> > 
> > Fixes: b4626a7f4892 ("CLK: Add Loongson1C clock support")
> > Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> > Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> > ---
> > 
> > v3:
> > - no changes
> > 
> > v2:
> > - Add Fixes and R-b tags
> > ---
> >   drivers/clk/loongson1/clk-loongson1c.c | 1 +
> >   1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/clk/loongson1/clk-loongson1c.c b/drivers/clk/loongson1/clk-loongson1c.c
> > index 703f87622cf5f..a6f9f20fc8b99 100644
> > --- a/drivers/clk/loongson1/clk-loongson1c.c
> > +++ b/drivers/clk/loongson1/clk-loongson1c.c
> > @@ -37,6 +37,7 @@ static const struct clk_div_table ahb_div_table[] = {
> >   	[1] = { .val = 1, .div = 4 },
> >   	[2] = { .val = 2, .div = 3 },
> >   	[3] = { .val = 3, .div = 3 },
> > +	[4] = { /* sentinel */ },
> 
> Sorry for being nitpicky here, but we don't need the trailing comma,
> since this is the last entry.

Good point.

Thanks,
Jonathan

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[PATCH v3 3/4] clk: hisilicon: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

In order that the end of a clk_div_table can be detected, it must be
terminated with a sentinel element (.div = 0).

Fixes: 6c81966107dc0 ("clk: hisilicon: Add clock driver for hi3559A SoC")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---

v3:
- no changes

v2:
- Add Fixes tag
---
 drivers/clk/hisilicon/clk-hi3559a.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/hisilicon/clk-hi3559a.c b/drivers/clk/hisilicon/clk-hi3559a.c
index 56012a3d02192..28c2a0630474d 100644
--- a/drivers/clk/hisilicon/clk-hi3559a.c
+++ b/drivers/clk/hisilicon/clk-hi3559a.c
@@ -611,8 +611,8 @@ static struct hisi_mux_clock hi3559av100_shub_mux_clks[] = {


 /* shub div clk */
-static struct clk_div_table shub_spi_clk_table[] = {{0, 8}, {1, 4}, {2, 2}};
-static struct clk_div_table shub_uart_div_clk_table[] = {{1, 8}, {2, 4}};
+static struct clk_div_table shub_spi_clk_table[] = {{0, 8}, {1, 4}, {2, 2}, {}};
+static struct clk_div_table shub_uart_div_clk_table[] = {{1, 8}, {2, 4}, {}};

 static struct hisi_divider_clock hi3559av100_shub_div_clks[] = {
 	{ HI3559AV100_SHUB_SPI_SOURCE_CLK, "clk_spi_clk", "shub_clk", 0, 0x20, 24, 2,
--
2.34.1

[PATCH v3 4/4] clk: clps711x: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

In order that the end of a clk_div_table can be detected, it must be
terminated with a sentinel element (.div = 0).

Fixes: 631c53478973d ("clk: Add CLPS711X clk driver")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
---

v3:
- no changes

v2:
- Add Fixes tag
---
 drivers/clk/clk-clps711x.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/clk/clk-clps711x.c b/drivers/clk/clk-clps711x.c
index a2c6486ef1708..d96d96c8752c7 100644
--- a/drivers/clk/clk-clps711x.c
+++ b/drivers/clk/clk-clps711x.c
@@ -28,11 +28,13 @@ static const struct clk_div_table spi_div_table[] = {
 	{ .val = 1, .div = 8, },
 	{ .val = 2, .div = 2, },
 	{ .val = 3, .div = 1, },
+	{}
 };

 static const struct clk_div_table timer_div_table[] = {
 	{ .val = 0, .div = 256, },
 	{ .val = 1, .div = 1, },
+	{}
 };

 struct clps711x_clk {
--
2.34.1

Re: [PATCH v3 4/4] clk: clps711x: Terminate clk_div_table with sentinel element

[Philippe Mathieu-Daudé]

On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> In order that the end of a clk_div_table can be detected, it must be
> terminated with a sentinel element (.div = 0).
> 
> Fixes: 631c53478973d ("clk: Add CLPS711X clk driver")
> Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> ---
> 
> v3:
> - no changes
> 
> v2:
> - Add Fixes tag
> ---
>   drivers/clk/clk-clps711x.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/clk/clk-clps711x.c b/drivers/clk/clk-clps711x.c
> index a2c6486ef1708..d96d96c8752c7 100644
> --- a/drivers/clk/clk-clps711x.c
> +++ b/drivers/clk/clk-clps711x.c
> @@ -28,11 +28,13 @@ static const struct clk_div_table spi_div_table[] = {
>   	{ .val = 1, .div = 8, },
>   	{ .val = 2, .div = 2, },
>   	{ .val = 3, .div = 1, },
> +	{}

Why not use the same style on all patches? Others developers looking
at this code will directly grab this is a sentinel section, instead of
wondering why this empty section is here.

         { /* sentinel */ }

Anyhow the patch logic is correct, so:
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

>   };
> 
>   static const struct clk_div_table timer_div_table[] = {
>   	{ .val = 0, .div = 256, },
>   	{ .val = 1, .div = 1, },
> +	{}

(same comment)

>   };
> 
>   struct clps711x_clk {
> --
> 2.34.1
> 

Re: [PATCH v3 4/4] clk: clps711x: Terminate clk_div_table with sentinel element

[Jonathan Neuschäfer]

[-- Attachment #1: Type: text/plain, Size: 1376 bytes --]

On Sat, Feb 05, 2022 at 01:13:00PM +0100, Philippe Mathieu-Daudé wrote:
> On 5/2/22 01:52, Jonathan Neuschäfer wrote:
> > In order that the end of a clk_div_table can be detected, it must be
> > terminated with a sentinel element (.div = 0).
> > 
> > Fixes: 631c53478973d ("clk: Add CLPS711X clk driver")
> > Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
> > ---
> > 
> > v3:
> > - no changes
> > 
> > v2:
> > - Add Fixes tag
> > ---
> >   drivers/clk/clk-clps711x.c | 2 ++
> >   1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/clk/clk-clps711x.c b/drivers/clk/clk-clps711x.c
> > index a2c6486ef1708..d96d96c8752c7 100644
> > --- a/drivers/clk/clk-clps711x.c
> > +++ b/drivers/clk/clk-clps711x.c
> > @@ -28,11 +28,13 @@ static const struct clk_div_table spi_div_table[] = {
> >   	{ .val = 1, .div = 8, },
> >   	{ .val = 2, .div = 2, },
> >   	{ .val = 3, .div = 1, },
> > +	{}
> 
> Why not use the same style on all patches? Others developers looking
> at this code will directly grab this is a sentinel section, instead of
> wondering why this empty section is here.
> 
>         { /* sentinel */ }

I found the {} style sufficient.
But ok, I'll go with { /* sentinel */ } now.

> 
> Anyhow the patch logic is correct, so:
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

Thanks!

Jonathan

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