[PATCH] ARM: S3C2410: Remove section mismatch warning

[PATCH] ARM: S3C2410: Remove section mismatch warning

[Tushar Behera]

Some of the functions and structures did not have _init or __initdata
attributes, even though they were referenced from functions / structures
with those attribute, resulting in section mismatches.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
---

The patch is rebased on v3.1-rc8.

The patch has only been build tested, they are not boot tested on any
hardware.

 arch/arm/mach-s3c2410/usb-simtec.c |    2 +-
 arch/arm/mach-s3c2410/usb-simtec.h |    2 +-
 arch/arm/mach-s3c2416/irq.c        |    2 +-
 arch/arm/mach-s3c2440/clock.c      |    4 ++--
 arch/arm/mach-s3c2443/irq.c        |    2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-s3c2410/usb-simtec.c b/arch/arm/mach-s3c2410/usb-simtec.c
index 29bd3d9..3a1028c 100644
--- a/arch/arm/mach-s3c2410/usb-simtec.c
+++ b/arch/arm/mach-s3c2410/usb-simtec.c
@@ -104,7 +104,7 @@ static struct s3c2410_hcd_info usb_simtec_info __initdata = {
 };
 
 
-int usb_simtec_init(void)
+int __init usb_simtec_init(void)
 {
 	int ret;
 
diff --git a/arch/arm/mach-s3c2410/usb-simtec.h b/arch/arm/mach-s3c2410/usb-simtec.h
index 03842ed..43cc88f 100644
--- a/arch/arm/mach-s3c2410/usb-simtec.h
+++ b/arch/arm/mach-s3c2410/usb-simtec.h
@@ -12,5 +12,5 @@
  * published by the Free Software Foundation.
 */
 
-extern int usb_simtec_init(void);
+extern int __init usb_simtec_init(void);
 
diff --git a/arch/arm/mach-s3c2416/irq.c b/arch/arm/mach-s3c2416/irq.c
index 28ad20d..153cb2f 100644
--- a/arch/arm/mach-s3c2416/irq.c
+++ b/arch/arm/mach-s3c2416/irq.c
@@ -234,7 +234,7 @@ static int __init s3c2416_irq_add(struct sys_device *sysdev)
 	return 0;
 }
 
-static struct sysdev_driver s3c2416_irq_driver = {
+static struct sysdev_driver s3c2416_irq_driver __initdata = {
 	.add		= s3c2416_irq_add,
 };
 
diff --git a/arch/arm/mach-s3c2440/clock.c b/arch/arm/mach-s3c2440/clock.c
index f9e6bda..3b3bec5 100644
--- a/arch/arm/mach-s3c2440/clock.c
+++ b/arch/arm/mach-s3c2440/clock.c
@@ -108,7 +108,7 @@ static struct clk s3c2440_clk_ac97 = {
 	.ctrlbit	= S3C2440_CLKCON_CAMERA,
 };
 
-static int s3c2440_clk_add(struct sys_device *sysdev)
+static int __init s3c2440_clk_add(struct sys_device *sysdev)
 {
 	struct clk *clock_upll;
 	struct clk *clock_h;
@@ -137,7 +137,7 @@ static int s3c2440_clk_add(struct sys_device *sysdev)
 	return 0;
 }
 
-static struct sysdev_driver s3c2440_clk_driver = {
+static struct sysdev_driver s3c2440_clk_driver __initdata = {
 	.add	= s3c2440_clk_add,
 };
 
diff --git a/arch/arm/mach-s3c2443/irq.c b/arch/arm/mach-s3c2443/irq.c
index 83ecb11..1d483d9 100644
--- a/arch/arm/mach-s3c2443/irq.c
+++ b/arch/arm/mach-s3c2443/irq.c
@@ -265,7 +265,7 @@ static int __init s3c2443_irq_add(struct sys_device *sysdev)
 	return 0;
 }
 
-static struct sysdev_driver s3c2443_irq_driver = {
+static struct sysdev_driver s3c2443_irq_driver __initdata = {
 	.add		= s3c2443_irq_add,
 };
 
-- 
1.7.4.1

[PATCH] ARM: S3C2410: Remove section mismatch warning

[Russell King - ARM Linux]

On Mon, Oct 03, 2011 at 03:10:41PM +0530, Tushar Behera wrote:
> Some of the functions and structures did not have _init or __initdata
> attributes, even though they were referenced from functions / structures
> with those attribute, resulting in section mismatches.

Firstly - it's a good idea to include the warnings which you're fixing
in the commit log text, so that people know exactly what is being fixed.

> diff --git a/arch/arm/mach-s3c2410/usb-simtec.c b/arch/arm/mach-s3c2410/usb-simtec.c
> index 29bd3d9..3a1028c 100644
> --- a/arch/arm/mach-s3c2410/usb-simtec.c
> +++ b/arch/arm/mach-s3c2410/usb-simtec.c
> @@ -104,7 +104,7 @@ static struct s3c2410_hcd_info usb_simtec_info __initdata = {
>  };
>  
>  
> -int usb_simtec_init(void)
> +int __init usb_simtec_init(void)
>  {
>  	int ret;
>  

This one looks fine.

> diff --git a/arch/arm/mach-s3c2416/irq.c b/arch/arm/mach-s3c2416/irq.c
> index 28ad20d..153cb2f 100644
> --- a/arch/arm/mach-s3c2416/irq.c
> +++ b/arch/arm/mach-s3c2416/irq.c
> @@ -234,7 +234,7 @@ static int __init s3c2416_irq_add(struct sys_device *sysdev)
>  	return 0;
>  }
>  
> -static struct sysdev_driver s3c2416_irq_driver = {
> +static struct sysdev_driver s3c2416_irq_driver __initdata = {
>  	.add		= s3c2416_irq_add,
>  };
>  

I remain entirely unconvinced that this is correct.  As a result of
the "sysdev_driver_register(&s3c2416_sysclass, &s3c2416_irq_driver);"
call, this structure is placed on a list.

If this structure is marked __initdata, then the memory behind the
structure will be freed and overwritten - however, it's still on a
list which might be walked.  Such a walk would cause a kernel oops
or might even be an exploitable security hole if that page ends up
in userspace - especially as said structure contains function calls
which would be called in privileged mode.

The same comment applies to the other sysdev driver structures you're
marking __initdata too.

[PATCH] ARM: S3C2410: Remove section mismatch warning

[Tushar Behera]

Hi Russell,

On Monday 03 October 2011 03:29 PM, Russell King - ARM Linux wrote:
> On Mon, Oct 03, 2011 at 03:10:41PM +0530, Tushar Behera wrote:
>> Some of the functions and structures did not have _init or __initdata
>> attributes, even though they were referenced from functions / structures
>> with those attribute, resulting in section mismatches.
>
> Firstly - it's a good idea to include the warnings which you're fixing
> in the commit log text, so that people know exactly what is being fixed.
>
Thanks for your review.

Sure, I will add it in next revision.

[ snip ]

>> diff --git a/arch/arm/mach-s3c2416/irq.c b/arch/arm/mach-s3c2416/irq.c
>> index 28ad20d..153cb2f 100644
>> --- a/arch/arm/mach-s3c2416/irq.c
>> +++ b/arch/arm/mach-s3c2416/irq.c
>> @@ -234,7 +234,7 @@ static int __init s3c2416_irq_add(struct sys_device *sysdev)
>>   	return 0;
>>   }
>>
>> -static struct sysdev_driver s3c2416_irq_driver = {
>> +static struct sysdev_driver s3c2416_irq_driver __initdata = {
>>   	.add		= s3c2416_irq_add,
>>   };
>>
>
> I remain entirely unconvinced that this is correct.  As a result of
> the "sysdev_driver_register(&s3c2416_sysclass,&s3c2416_irq_driver);"
> call, this structure is placed on a list.
>
> If this structure is marked __initdata, then the memory behind the
> structure will be freed and overwritten - however, it's still on a
> list which might be walked.  Such a walk would cause a kernel oops
> or might even be an exploitable security hole if that page ends up
> in userspace - especially as said structure contains function calls
> which would be called in privileged mode.
>

The function s3c2416_irq_add() is defined with __init attribute. Also a 
cascade of functions called from s3c2416_irq_add() are also defined with 
__init attribute.

Would it be a good idea to remove __init attribute of all these 
functions (there are 2 of them) called from s3c2416_irq_add() instead?

> The same comment applies to the other sysdev driver structures you're
> marking __initdata too.

-- 
Tushar Behera