RE: [PATCH] tty: serial: fsl_lpuart: Constify struct lpuart_soc_data

From: Sherry Sun
Date: Sat Jun 28 2025 - 04:04:11 EST




> -----Original Message-----
> From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> Sent: Saturday, June 28, 2025 2:35 PM
> To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>; Jiri Slaby
> <jirislaby@xxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx; kernel-janitors@xxxxxxxxxxxxxxx; Christophe
> JAILLET <christophe.jaillet@xxxxxxxxxx>; linux-serial@xxxxxxxxxxxxxxx
> Subject: [PATCH] tty: serial: fsl_lpuart: Constify struct lpuart_soc_data
>
> 'struct lpuart_soc_data' are not modified in this driver.
>
> Constifying these structures moves some data to a read-only section, so
> increases overall security.
>
> This also makes the code more consistent.
>
> On a x86_64, with allmodconfig, as an example:
> Before:
> ======
> text data bss dec hex filename
> 172668 23470 128 196266 2feaa
> drivers/tty/serial/fsl_lpuart.o
>
> After:
> =====
> text data bss dec hex filename
> 172924 23214 128 196266 2feaa
> drivers/tty/serial/fsl_lpuart.o
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

Reviewed-by: Sherry Sun <sherry.sun@xxxxxxx>

Best Regards
Sherry


> ---
> Compile tested only
> ---
> drivers/tty/serial/fsl_lpuart.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index
> 2790b4078e7e..c9519e649e82 100644
> --- a/drivers/tty/serial/fsl_lpuart.c
> +++ b/drivers/tty/serial/fsl_lpuart.c
> @@ -318,27 +318,27 @@ static const struct lpuart_soc_data ls1028a_data = {
> .rx_watermark = 0,
> };
>
> -static struct lpuart_soc_data imx7ulp_data = {
> +static const struct lpuart_soc_data imx7ulp_data = {
> .devtype = IMX7ULP_LPUART,
> .iotype = UPIO_MEM32,
> .reg_off = IMX_REG_OFF,
> .rx_watermark = 1,
> };
>
> -static struct lpuart_soc_data imx8ulp_data = {
> +static const struct lpuart_soc_data imx8ulp_data = {
> .devtype = IMX8ULP_LPUART,
> .iotype = UPIO_MEM32,
> .reg_off = IMX_REG_OFF,
> .rx_watermark = 3,
> };
>
> -static struct lpuart_soc_data imx8qxp_data = {
> +static const struct lpuart_soc_data imx8qxp_data = {
> .devtype = IMX8QXP_LPUART,
> .iotype = UPIO_MEM32,
> .reg_off = IMX_REG_OFF,
> .rx_watermark = 7, /* A lower watermark is ideal for low baud rates.
> */ }; -static struct lpuart_soc_data imxrt1050_data = {
> +static const struct lpuart_soc_data imxrt1050_data = {
> .devtype = IMXRT1050_LPUART,
> .iotype = UPIO_MEM32,
> .reg_off = IMX_REG_OFF,
> --
> 2.50.0
>