RE: [PATCH] clk: visconti: pll: use kzalloc_flex

From: nobuhiro.iwamatsu.x90

Date: Mon Mar 30 2026 - 22:43:14 EST


Hi Rosen,

Thanks for your patch.

> -----Original Message-----
> From: Rosen Penev <rosenp@xxxxxxxxx>
> Sent: Thursday, March 26, 2026 1:23 PM
> To: linux-clk@xxxxxxxxxxxxxxx
> Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>; Stephen Boyd <sboyd@xxxxxxxxxx>; iwamatsu nobuhiro(岩松 信洋
> □DITC○CPT) <nobuhiro.iwamatsu.x90@mail.toshiba>; Kees Cook <kees@xxxxxxxxxx>; Gustavo A. R. Silva
> <gustavoars@xxxxxxxxxx>; moderated list:ARM/TOSHIBA VISCONTI ARCHITECTURE
> <linux-arm-kernel@xxxxxxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>; open list:KERNEL HARDENING (not
> covered by other areas):Keyword:\b__counted_by(_le|_be)?\b <linux-hardening@xxxxxxxxxxxxxxx>
> Subject: [PATCH] clk: visconti: pll: use kzalloc_flex
>
> Simplify allocation by using a flexible array member and kzalloc_flex.
>
> Add __counted_by for extra runtime analysis. Assign after allocation as required by __counted_by.
>
> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>

Acked-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.x90@mail.toshiba>

Best regards,
Nobuhiro
> ---
> drivers/clk/visconti/pll.c | 17 +++++++----------
> 1 file changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/clk/visconti/pll.c b/drivers/clk/visconti/pll.c index 6fd02c4b641e..ca29d12f9316 100644
> --- a/drivers/clk/visconti/pll.c
> +++ b/drivers/clk/visconti/pll.c
> @@ -21,9 +21,9 @@ struct visconti_pll {
> void __iomem *pll_base;
> spinlock_t *lock;
> unsigned long flags;
> - const struct visconti_pll_rate_table *rate_table;
> size_t rate_count;
> struct visconti_pll_provider *ctx;
> + struct visconti_pll_rate_table rate_table[] __counted_by(rate_count);
> };
>
> #define PLL_CONF_REG 0x0000
> @@ -255,10 +255,6 @@ static struct clk_hw *visconti_register_pll(struct visconti_pll_provider *ctx,
> size_t len;
> int ret;
>
> - pll = kzalloc_obj(*pll);
> - if (!pll)
> - return ERR_PTR(-ENOMEM);
> -
> init.name = name;
> init.flags = CLK_IGNORE_UNUSED;
> init.parent_names = &parent_name;
> @@ -266,11 +262,13 @@ static struct clk_hw *visconti_register_pll(struct visconti_pll_provider *ctx,
>
> for (len = 0; rate_table[len].rate != 0; )
> len++;
> +
> + pll = kzalloc_flex(*pll, rate_table, len);
> + if (!pll)
> + return ERR_PTR(-ENOMEM);
> +
> pll->rate_count = len;
> - pll->rate_table = kmemdup_array(rate_table,
> - pll->rate_count, sizeof(*pll->rate_table),
> - GFP_KERNEL);
> - WARN(!pll->rate_table, "%s: could not allocate rate table for %s\n", __func__, name);
> + memcpy(pll->rate_table, rate_table, len * sizeof(*pll->rate_table));
>
> init.ops = &visconti_pll_ops;
> pll->hw.init = &init;
> @@ -282,7 +280,6 @@ static struct clk_hw *visconti_register_pll(struct visconti_pll_provider *ctx,
> ret = clk_hw_register(NULL, &pll->hw);
> if (ret) {
> pr_err("failed to register pll clock %s : %d\n", name, ret);
> - kfree(pll->rate_table);
> kfree(pll);
> pll_hw_clk = ERR_PTR(ret);
> }
> --
> 2.53.0