drivers/clk/microchip/clk-mpfs-ccc.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-)
In various places, string buffers of a fixed size are allocated, and
filled using snprintf() with the same fixed size, which is error-prone.
Replace this by calling devm_kasprintf() instead, which always uses the
appropriate size.
While at it, remove an unneeded intermediate variable, which allows us
to drop a cast as a bonus.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/clk/microchip/clk-mpfs-ccc.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/clk/microchip/clk-mpfs-ccc.c b/drivers/clk/microchip/clk-mpfs-ccc.c
index 32aae880a14f3b1c..0ddc73e07be42973 100644
--- a/drivers/clk/microchip/clk-mpfs-ccc.c
+++ b/drivers/clk/microchip/clk-mpfs-ccc.c
@@ -164,12 +164,11 @@ static int mpfs_ccc_register_outputs(struct device *dev, struct mpfs_ccc_out_hw_
for (unsigned int i = 0; i < num_clks; i++) {
struct mpfs_ccc_out_hw_clock *out_hw = &out_hws[i];
- char *name = devm_kzalloc(dev, 23, GFP_KERNEL);
+ char *name = devm_kasprintf(dev, GFP_KERNEL, "%s_out%u", parent->name, i);
if (!name)
return -ENOMEM;
- snprintf(name, 23, "%s_out%u", parent->name, i);
out_hw->divider.hw.init = CLK_HW_INIT_HW(name, &parent->hw, &clk_divider_ops, 0);
out_hw->divider.reg = data->pll_base[i / MPFS_CCC_OUTPUTS_PER_PLL] +
out_hw->reg_offset;
@@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
for (unsigned int i = 0; i < num_clks; i++) {
struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
- char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
- if (!name)
+ pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
+ strchrnul(dev->of_node->full_name, '@'), i);
+ if (!pll_hw->name)
return -ENOMEM;
pll_hw->base = data->pll_base[i];
- snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
- pll_hw->name = (const char *)name;
pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
pll_hw->parents,
&mpfs_ccc_pll_ops, 0);
--
2.25.1On 03.01.2023 18:45, Geert Uytterhoeven wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> In various places, string buffers of a fixed size are allocated, and
> filled using snprintf() with the same fixed size, which is error-prone.
>
> Replace this by calling devm_kasprintf() instead, which always uses the
> appropriate size.
>
> While at it, remove an unneeded intermediate variable, which allows us
> to drop a cast as a bonus.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Applied to clk-microchip-fixes, thanks!
> ---
> drivers/clk/microchip/clk-mpfs-ccc.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/clk/microchip/clk-mpfs-ccc.c b/drivers/clk/microchip/clk-mpfs-ccc.c
> index 32aae880a14f3b1c..0ddc73e07be42973 100644
> --- a/drivers/clk/microchip/clk-mpfs-ccc.c
> +++ b/drivers/clk/microchip/clk-mpfs-ccc.c
> @@ -164,12 +164,11 @@ static int mpfs_ccc_register_outputs(struct device *dev, struct mpfs_ccc_out_hw_
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_out_hw_clock *out_hw = &out_hws[i];
> - char *name = devm_kzalloc(dev, 23, GFP_KERNEL);
> + char *name = devm_kasprintf(dev, GFP_KERNEL, "%s_out%u", parent->name, i);
>
> if (!name)
> return -ENOMEM;
>
> - snprintf(name, 23, "%s_out%u", parent->name, i);
> out_hw->divider.hw.init = CLK_HW_INIT_HW(name, &parent->hw, &clk_divider_ops, 0);
> out_hw->divider.reg = data->pll_base[i / MPFS_CCC_OUTPUTS_PER_PLL] +
> out_hw->reg_offset;
> @@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
> - char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
>
> - if (!name)
> + pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
> + strchrnul(dev->of_node->full_name, '@'), i);
> + if (!pll_hw->name)
> return -ENOMEM;
>
> pll_hw->base = data->pll_base[i];
> - snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
> - pll_hw->name = (const char *)name;
> pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
> pll_hw->parents,
> &mpfs_ccc_pll_ops, 0);
> --
> 2.25.1
>
Hey Claudiu,
Could you pick this one up when you get a chance please?
Thanks,
Conor.
On Tue, Jan 03, 2023 at 05:45:30PM +0100, Geert Uytterhoeven wrote:
> In various places, string buffers of a fixed size are allocated, and
> filled using snprintf() with the same fixed size, which is error-prone.
>
> Replace this by calling devm_kasprintf() instead, which always uses the
> appropriate size.
>
> While at it, remove an unneeded intermediate variable, which allows us
> to drop a cast as a bonus.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> drivers/clk/microchip/clk-mpfs-ccc.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/clk/microchip/clk-mpfs-ccc.c b/drivers/clk/microchip/clk-mpfs-ccc.c
> index 32aae880a14f3b1c..0ddc73e07be42973 100644
> --- a/drivers/clk/microchip/clk-mpfs-ccc.c
> +++ b/drivers/clk/microchip/clk-mpfs-ccc.c
> @@ -164,12 +164,11 @@ static int mpfs_ccc_register_outputs(struct device *dev, struct mpfs_ccc_out_hw_
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_out_hw_clock *out_hw = &out_hws[i];
> - char *name = devm_kzalloc(dev, 23, GFP_KERNEL);
> + char *name = devm_kasprintf(dev, GFP_KERNEL, "%s_out%u", parent->name, i);
>
> if (!name)
> return -ENOMEM;
>
> - snprintf(name, 23, "%s_out%u", parent->name, i);
> out_hw->divider.hw.init = CLK_HW_INIT_HW(name, &parent->hw, &clk_divider_ops, 0);
> out_hw->divider.reg = data->pll_base[i / MPFS_CCC_OUTPUTS_PER_PLL] +
> out_hw->reg_offset;
> @@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
> - char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
>
> - if (!name)
> + pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
> + strchrnul(dev->of_node->full_name, '@'), i);
> + if (!pll_hw->name)
> return -ENOMEM;
>
> pll_hw->base = data->pll_base[i];
> - snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
> - pll_hw->name = (const char *)name;
> pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
> pll_hw->parents,
> &mpfs_ccc_pll_ops, 0);
> --
> 2.25.1
>
Hi, Conor, On 11.01.2023 21:26, Conor Dooley wrote: > Hey Claudiu, > > Could you pick this one up when you get a chance please? It's already in my tree, not pushed yet, though. It'll do it soon. I'll let you know. Claudiu > > Thanks,
On Tue, Jan 03, 2023 at 05:45:30PM +0100, Geert Uytterhoeven wrote:
> In various places, string buffers of a fixed size are allocated, and
> filled using snprintf() with the same fixed size, which is error-prone.
>
> Replace this by calling devm_kasprintf() instead, which always uses the
> appropriate size.
>
> While at it, remove an unneeded intermediate variable, which allows us
> to drop a cast as a bonus.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
I half wonder if this should actually have a fixes tag too. Since it
used what came after the @ in $full_name, it'd be possible to create
(an incorrect) DTS that would lead to a clash between pll names &
therefore probe would fail.
The tag would be:
Fixes: d39fb172760e ("clk: microchip: add PolarFire SoC fabric clock support")
Either way, thanks for pointing out a function that does exactly what I
initially wanted to do but could not find! Glad to be rid of those
"oddly specific" allocations.
Thanks,
Conor.
> ---
> drivers/clk/microchip/clk-mpfs-ccc.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/clk/microchip/clk-mpfs-ccc.c b/drivers/clk/microchip/clk-mpfs-ccc.c
> index 32aae880a14f3b1c..0ddc73e07be42973 100644
> --- a/drivers/clk/microchip/clk-mpfs-ccc.c
> +++ b/drivers/clk/microchip/clk-mpfs-ccc.c
> @@ -164,12 +164,11 @@ static int mpfs_ccc_register_outputs(struct device *dev, struct mpfs_ccc_out_hw_
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_out_hw_clock *out_hw = &out_hws[i];
> - char *name = devm_kzalloc(dev, 23, GFP_KERNEL);
> + char *name = devm_kasprintf(dev, GFP_KERNEL, "%s_out%u", parent->name, i);
>
> if (!name)
> return -ENOMEM;
>
> - snprintf(name, 23, "%s_out%u", parent->name, i);
> out_hw->divider.hw.init = CLK_HW_INIT_HW(name, &parent->hw, &clk_divider_ops, 0);
> out_hw->divider.reg = data->pll_base[i / MPFS_CCC_OUTPUTS_PER_PLL] +
> out_hw->reg_offset;
> @@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
> - char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
>
> - if (!name)
> + pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
> + strchrnul(dev->of_node->full_name, '@'), i);
> + if (!pll_hw->name)
> return -ENOMEM;
>
> pll_hw->base = data->pll_base[i];
> - snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
> - pll_hw->name = (const char *)name;
> pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
> pll_hw->parents,
> &mpfs_ccc_pll_ops, 0);
> --
> 2.25.1
>
>
Hi Conor,
On Tue, Jan 3, 2023 at 6:32 PM Conor Dooley <conor@kernel.org> wrote:
> On Tue, Jan 03, 2023 at 05:45:30PM +0100, Geert Uytterhoeven wrote:
> > In various places, string buffers of a fixed size are allocated, and
> > filled using snprintf() with the same fixed size, which is error-prone.
> >
> > Replace this by calling devm_kasprintf() instead, which always uses the
> > appropriate size.
> >
> > While at it, remove an unneeded intermediate variable, which allows us
> > to drop a cast as a bonus.
> >
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> Tested-by: Conor Dooley <conor.dooley@microchip.com>
Thanks!
> I half wonder if this should actually have a fixes tag too. Since it
> used what came after the @ in $full_name, it'd be possible to create
> (an incorrect) DTS that would lead to a clash between pll names &
> therefore probe would fail.
> The tag would be:
> Fixes: d39fb172760e ("clk: microchip: add PolarFire SoC fabric clock support")
But I don't change any of that in my patch?
/me confused.
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
On Wed, Jan 04, 2023 at 02:26:53PM +0100, Geert Uytterhoeven wrote:
> Hi Conor,
>
> On Tue, Jan 3, 2023 at 6:32 PM Conor Dooley <conor@kernel.org> wrote:
> > I half wonder if this should actually have a fixes tag too. Since it
> > used what came after the @ in $full_name, it'd be possible to create
> > (an incorrect) DTS that would lead to a clash between pll names &
> > therefore probe would fail.
> > The tag would be:
> > Fixes: d39fb172760e ("clk: microchip: add PolarFire SoC fabric clock support")
>
> But I don't change any of that in my patch?
> /me confused.
The numbers in there were chosen to fit exactly what is in mpfs.dtsi
(IOW the correct node address), so doing
@@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
for (unsigned int i = 0; i < num_clks; i++) {
struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
- char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
- if (!name)
+ pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
+ strchrnul(dev->of_node->full_name, '@'), i);
+ if (!pll_hw->name)
return -ENOMEM;
pll_hw->base = data->pll_base[i];
- snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
- pll_hw->name = (const char *)name;
pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
pll_hw->parents,
&mpfs_ccc_pll_ops, 0);
means that we no longer have to worry that someone would provide a
device tree with a node address that would make "ccc<node_address>_pll<N>"
exceed 18 characters. If that happened, the <N> would be cut off & both
pll 0 & 1 would be named identically. If that happens, pll1 would fail
to register.
Or am I misunderstanding something? Probably am..
Thanks,
Conor.
Hi Conor,
On Wed, Jan 4, 2023 at 2:40 PM Conor Dooley <conor@kernel.org> wrote:
> On Wed, Jan 04, 2023 at 02:26:53PM +0100, Geert Uytterhoeven wrote:
> > On Tue, Jan 3, 2023 at 6:32 PM Conor Dooley <conor@kernel.org> wrote:
> > > I half wonder if this should actually have a fixes tag too. Since it
> > > used what came after the @ in $full_name, it'd be possible to create
> > > (an incorrect) DTS that would lead to a clash between pll names &
> > > therefore probe would fail.
> > > The tag would be:
> > > Fixes: d39fb172760e ("clk: microchip: add PolarFire SoC fabric clock support")
> >
> > But I don't change any of that in my patch?
> > /me confused.
>
> The numbers in there were chosen to fit exactly what is in mpfs.dtsi
> (IOW the correct node address), so doing
> @@ -201,14 +200,13 @@ static int mpfs_ccc_register_plls(struct device *dev, struct mpfs_ccc_pll_hw_clo
>
> for (unsigned int i = 0; i < num_clks; i++) {
> struct mpfs_ccc_pll_hw_clock *pll_hw = &pll_hws[i];
> - char *name = devm_kzalloc(dev, 18, GFP_KERNEL);
>
> - if (!name)
> + pll_hw->name = devm_kasprintf(dev, GFP_KERNEL, "ccc%s_pll%u",
> + strchrnul(dev->of_node->full_name, '@'), i);
> + if (!pll_hw->name)
> return -ENOMEM;
>
> pll_hw->base = data->pll_base[i];
> - snprintf(name, 18, "ccc%s_pll%u", strchrnul(dev->of_node->full_name, '@'), i);
> - pll_hw->name = (const char *)name;
> pll_hw->hw.init = CLK_HW_INIT_PARENTS_DATA_FIXED_SIZE(pll_hw->name,
> pll_hw->parents,
> &mpfs_ccc_pll_ops, 0);
>
> means that we no longer have to worry that someone would provide a
> device tree with a node address that would make "ccc<node_address>_pll<N>"
> exceed 18 characters. If that happened, the <N> would be cut off & both
> pll 0 & 1 would be named identically. If that happens, pll1 would fail
> to register.
Oh right. Yeah, before we would get collisions, now we would get
a different broken system.
DTS garbage in, garbage behavior out ;-)
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
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