Re: [PATCH] clk: imx: pll14xx: initialize flags to 0

From: Marc Gonzalez <marc.w.gonzalez@free.fr>
To: Peng Fan <peng.fan@nxp.com>
Cc: Stephen Boyd <sboyd@kernel.org>,
	linux-clk <linux-clk@vger.kernel.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] clk: imx: pll14xx: initialize flags to 0
Date: Tue, 5 Nov 2019 10:47:50 +0100	[thread overview]
Message-ID: <5fc2dfd6-ae59-6af8-0423-ddc8e0b4f78f@free.fr> (raw)
In-Reply-To: <1572938372-7006-1-git-send-email-peng.fan@nxp.com>

On 05/11/2019 08:21, Peng Fan wrote:

> From: Peng Fan <peng.fan@nxp.com>
> 
> init.flags is initialized with value from pll_clk->flags, however
> imx_1443x_pll and imx_1416x_pll are not static structure, so flags
> might be random value. So let's initialize flags as 0 now.

This is incorrect. When using an initializer list, struct members
not explicitly specified are initialized to 0.

https://port70.net/~nsz/c/c11/n1570.html#6.7.9p19

> The initialization shall occur in initializer list order, each
> initializer provided for a particular subobject overriding any
> previously listed initializer for the same subobject; all
> subobjects that are not initialized explicitly shall be initialized
> implicitly the same as objects that have static storage duration.
(You might point out that the kernel is compiled with -std=gnu89 not C11,
but GCC's semantics are the same.)

https://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated-Inits

> diff --git a/drivers/clk/imx/clk-pll14xx.c b/drivers/clk/imx/clk-pll14xx.c
> index fa76e04251c4..a7f1c1abe664 100644
> --- a/drivers/clk/imx/clk-pll14xx.c
> +++ b/drivers/clk/imx/clk-pll14xx.c
> @@ -65,12 +65,14 @@ struct imx_pll14xx_clk imx_1443x_pll = {
>  	.type = PLL_1443X,
>  	.rate_table = imx_pll1443x_tbl,
>  	.rate_count = ARRAY_SIZE(imx_pll1443x_tbl),
> +	.flags = 0,
>  };

What tree is this patch based on?

https://elixir.bootlin.com/linux/v5.4-rc1/source/drivers/clk/imx/clk-pll14xx.c#L65

Regards.