[PATCH] rtc: rx6110: Constify struct regmap_config

Christophe JAILLET posted 1 patch 2 weeks ago
drivers/rtc/rtc-rx6110.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
[PATCH] rtc: rx6110: Constify struct regmap_config
Posted by Christophe JAILLET 2 weeks ago
'regmap_spi_config' and 'regmap_i2c_config' are not modified in this diver
and are only used as a const struct regmap_config.

Constifying these structures moves some data to a read-only section, so
increase overall security.

On a x86_64, with allmodconfig:
Before:
   text	   data	    bss	    dec	    hex	filename
   8896	   1554	     32	  10482	   28f2	drivers/rtc/rtc-rx6110.o

After:
   text	   data	    bss	    dec	    hex	filename
   9536	    914	     32	  10482	   28f2	drivers/rtc/rtc-rx6110.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 drivers/rtc/rtc-rx6110.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/rtc-rx6110.c b/drivers/rtc/rtc-rx6110.c
index 834274db8c3f..af6dd6ccbe3b 100644
--- a/drivers/rtc/rtc-rx6110.c
+++ b/drivers/rtc/rtc-rx6110.c
@@ -330,7 +330,7 @@ static int rx6110_probe(struct rx6110_data *rx6110, struct device *dev)
 }
 
 #if IS_ENABLED(CONFIG_SPI_MASTER)
-static struct regmap_config regmap_spi_config = {
+static const struct regmap_config regmap_spi_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = RX6110_REG_IRQ,
@@ -410,7 +410,7 @@ static void rx6110_spi_unregister(void)
 #endif /* CONFIG_SPI_MASTER */
 
 #if IS_ENABLED(CONFIG_I2C)
-static struct regmap_config regmap_i2c_config = {
+static const struct regmap_config regmap_i2c_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.max_register = RX6110_REG_IRQ,
-- 
2.45.0
Re: [PATCH] rtc: rx6110: Constify struct regmap_config
Posted by Alexandre Belloni 1 week, 4 days ago
On Sun, 05 May 2024 00:43:07 +0200, Christophe JAILLET wrote:
> 'regmap_spi_config' and 'regmap_i2c_config' are not modified in this diver
> and are only used as a const struct regmap_config.
> 
> Constifying these structures moves some data to a read-only section, so
> increase overall security.
> 
> On a x86_64, with allmodconfig:
> Before:
>    text	   data	    bss	    dec	    hex	filename
>    8896	   1554	     32	  10482	   28f2	drivers/rtc/rtc-rx6110.o
> 
> [...]

Applied, thanks!

[1/1] rtc: rx6110: Constify struct regmap_config
      https://git.kernel.org/abelloni/c/6a216cbadbe0

Best regards,

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com