[PATCH 0/3] Removing dead code

[PATCH 0/3] Removing dead code

[Christian Dietrich]

Hi all!
       
        As part of the VAMOS[0] research project at the University of
Erlangen we are looking at multiple integrity errors in linux'
configuration system.

        I've been running a check on the sound/ sourcetree for
config Items not defined in Kconfig and found 3 such cases. Sourcecode
blocks depending on these Items are not reachable from a vanilla
kernel -- dead code. I've seen such dead blocks made on purpose
e.g. while integrating new features into the kernel but generally
they're just useless.

        Each of the patches in this patchset removes on such dead
config Item, I'd be glad if you consider applying them. I've been
doing deeper analysis of such issues before and can do so again but
I'm not so sure they were fastly usefull.

        I build the patches against a vanilla kernel in order to
try if the kernel compiles with this patches

        Please keep me informed of this patch getting confirmed /
merged so we can keep track of it.

Regards

        Christian Dietrich

[0] http://vamos1.informatik.uni-erlangen.de/

Christian Dietrich (3):
  sound/oss: Remove dead CONFIG_SOFTOSS*
  sound/soc/atmel: Remove dead CONFIG_AT32_ENHANCED_PORTMUX
  sound/isa/gus: Remove dead CONFIG_SND_DEBUG_ROM

 sound/isa/gus/interwave.c        |    8 --------
 sound/oss/vidc.c                 |    3 ---
 sound/soc/atmel/playpaq_wm8510.c |    9 ---------
 3 files changed, 0 insertions(+), 20 deletions(-)

[PATCH 1/3] sound/oss: Remove dead CONFIG_SOFTOSS*

[Christian Dietrich]

CONFIG_SOFTOSS* doesn't exist in Kconfig or somewhere
else, therefore removing all references for it from the source code.

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 sound/oss/vidc.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)

diff --git a/sound/oss/vidc.c b/sound/oss/vidc.c
index ac39a53..f0e0caa 100644
--- a/sound/oss/vidc.c
+++ b/sound/oss/vidc.c
@@ -491,9 +491,6 @@ static void __init attach_vidc(struct address_info *hw_config)
 	vidc_adev = adev;
 	vidc_mixer_set(SOUND_MIXER_VOLUME, (85 | 85 << 8));
 
-#if defined(CONFIG_SOUND_SOFTOSS) || defined(CONFIG_SOUND_SOFTOSS_MODULE)
-	softoss_dev = adev;
-#endif
 	return;
 
 irq_failed:
-- 
1.7.0.4

Re: [PATCH 1/3] sound/oss: Remove dead CONFIG_SOFTOSS*

[Takashi Iwai]

At Wed, 21 Jul 2010 14:35:17 +0200,
Christian Dietrich wrote:
> 
> CONFIG_SOFTOSS* doesn't exist in Kconfig or somewhere
> else, therefore removing all references for it from the source code.
> 
> Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>

Applied this one.  Thanks.


Takashi

> ---
>  sound/oss/vidc.c |    3 ---
>  1 files changed, 0 insertions(+), 3 deletions(-)
> 
> diff --git a/sound/oss/vidc.c b/sound/oss/vidc.c
> index ac39a53..f0e0caa 100644
> --- a/sound/oss/vidc.c
> +++ b/sound/oss/vidc.c
> @@ -491,9 +491,6 @@ static void __init attach_vidc(struct address_info *hw_config)
>  	vidc_adev = adev;
>  	vidc_mixer_set(SOUND_MIXER_VOLUME, (85 | 85 << 8));
>  
> -#if defined(CONFIG_SOUND_SOFTOSS) || defined(CONFIG_SOUND_SOFTOSS_MODULE)
> -	softoss_dev = adev;
> -#endif
>  	return;
>  
>  irq_failed:
> -- 
> 1.7.0.4
> 

[PATCH 2/3] sound/soc/atmel: Remove dead CONFIG_AT32_ENHANCED_PORTMUX

[Christian Dietrich]

CONFIG_AT32_ENCHANCED_PORTMUX doesn't exist in Kconfig or somewhere
else, therefore removing all references for it from the source code.

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 sound/soc/atmel/playpaq_wm8510.c |    9 ---------
 1 files changed, 0 insertions(+), 9 deletions(-)

diff --git a/sound/soc/atmel/playpaq_wm8510.c b/sound/soc/atmel/playpaq_wm8510.c
index 9df4c68..fbd17e9 100644
--- a/sound/soc/atmel/playpaq_wm8510.c
+++ b/sound/soc/atmel/playpaq_wm8510.c
@@ -425,11 +425,6 @@ static int __init playpaq_asoc_init(void)
 	clk_set_rate(CODEC_CLK, 12000000);
 	clk_enable(CODEC_CLK);
 
-#if defined CONFIG_AT32_ENHANCED_PORTMUX
-	at32_select_periph(MCLK_PIN, MCLK_PERIPH, 0);
-#endif
-
-
 	/*
 	 * Create and register platform device
 	 */
@@ -496,10 +491,6 @@ static void __exit playpaq_asoc_exit(void)
 		_pll0 = NULL;
 	}
 
-#if defined CONFIG_AT32_ENHANCED_PORTMUX
-	at32_free_pin(MCLK_PIN);
-#endif
-
 	platform_device_unregister(playpaq_snd_device);
 	playpaq_snd_device = NULL;
 }
-- 
1.7.0.4

Re: [PATCH 2/3] sound/soc/atmel: Remove dead CONFIG_AT32_ENHANCED_PORTMUX

[Mark Brown]

On Wed, Jul 21, 2010 at 02:35:41PM +0200, Christian Dietrich wrote:
> CONFIG_AT32_ENCHANCED_PORTMUX doesn't exist in Kconfig or somewhere
> else, therefore removing all references for it from the source code.
> 
> Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>

Please remember to CC maintainers on patches - I've added Geoffrey.

> ---
>  sound/soc/atmel/playpaq_wm8510.c |    9 ---------
>  1 files changed, 0 insertions(+), 9 deletions(-)
> 
> diff --git a/sound/soc/atmel/playpaq_wm8510.c b/sound/soc/atmel/playpaq_wm8510.c
> index 9df4c68..fbd17e9 100644
> --- a/sound/soc/atmel/playpaq_wm8510.c
> +++ b/sound/soc/atmel/playpaq_wm8510.c
> @@ -425,11 +425,6 @@ static int __init playpaq_asoc_init(void)
>  	clk_set_rate(CODEC_CLK, 12000000);
>  	clk_enable(CODEC_CLK);
>  
> -#if defined CONFIG_AT32_ENHANCED_PORTMUX
> -	at32_select_periph(MCLK_PIN, MCLK_PERIPH, 0);
> -#endif
> -
> -
>  	/*
>  	 * Create and register platform device
>  	 */
> @@ -496,10 +491,6 @@ static void __exit playpaq_asoc_exit(void)
>  		_pll0 = NULL;
>  	}
>  
> -#if defined CONFIG_AT32_ENHANCED_PORTMUX
> -	at32_free_pin(MCLK_PIN);
> -#endif
> -
>  	platform_device_unregister(playpaq_snd_device);
>  	playpaq_snd_device = NULL;
>  }
> -- 
> 1.7.0.4
> 

[PATCH 3/3] sound/isa/gus: Remove dead CONFIG_SND_DEBUG_ROM

[Christian Dietrich]

CONFIG_SND_DEBUG_ROM doesn't exist in Kconfig, therefore it is never
defined and we can remove all references to it. If it should stay as a
debug flag, perhaps it shouldn't be named CONFIG_

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 sound/isa/gus/interwave.c |    8 --------
 1 files changed, 0 insertions(+), 8 deletions(-)

diff --git a/sound/isa/gus/interwave.c b/sound/isa/gus/interwave.c
index c7b80e4..ac60c7d 100644
--- a/sound/isa/gus/interwave.c
+++ b/sound/isa/gus/interwave.c
@@ -442,19 +442,11 @@ static void __devinit snd_interwave_detect_memory(struct snd_gus_card * gus)
 	for (bank_pos = 0; bank_pos < 16L * 1024L * 1024L; bank_pos += 4L * 1024L * 1024L) {
 		for (i = 0; i < 8; ++i)
 			iwave[i] = snd_gf1_peek(gus, bank_pos + i);
-#ifdef CONFIG_SND_DEBUG_ROM
-		printk(KERN_DEBUG "ROM at 0x%06x = %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", bank_pos,
-		       iwave[0], iwave[1], iwave[2], iwave[3],
-		       iwave[4], iwave[5], iwave[6], iwave[7]);
-#endif
 		if (strncmp(iwave, "INTRWAVE", 8))
 			continue;	/* first check */
 		csum = 0;
 		for (i = 0; i < sizeof(struct rom_hdr); i++)
 			csum += snd_gf1_peek(gus, bank_pos + i);
-#ifdef CONFIG_SND_DEBUG_ROM
-		printk(KERN_DEBUG "ROM checksum = 0x%x (computed)\n", csum);
-#endif
 		if (csum != 0)
 			continue;	/* not valid rom */
 		gus->gf1.rom_banks++;
-- 
1.7.0.4

Re: [PATCH 3/3] sound/isa/gus: Remove dead CONFIG_SND_DEBUG_ROM

[Takashi Iwai]

At Wed, 21 Jul 2010 14:36:02 +0200,
Christian Dietrich wrote:
> 
> CONFIG_SND_DEBUG_ROM doesn't exist in Kconfig, therefore it is never
> defined and we can remove all references to it. If it should stay as a
> debug flag, perhaps it shouldn't be named CONFIG_
> 
> Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>

This is rather a debug code, so it's often useful to keep as is.
At bets, we can rename the ifdef without CONFIG_ prefix.


thanks,

Takashi

> ---
>  sound/isa/gus/interwave.c |    8 --------
>  1 files changed, 0 insertions(+), 8 deletions(-)
> 
> diff --git a/sound/isa/gus/interwave.c b/sound/isa/gus/interwave.c
> index c7b80e4..ac60c7d 100644
> --- a/sound/isa/gus/interwave.c
> +++ b/sound/isa/gus/interwave.c
> @@ -442,19 +442,11 @@ static void __devinit snd_interwave_detect_memory(struct snd_gus_card * gus)
>  	for (bank_pos = 0; bank_pos < 16L * 1024L * 1024L; bank_pos += 4L * 1024L * 1024L) {
>  		for (i = 0; i < 8; ++i)
>  			iwave[i] = snd_gf1_peek(gus, bank_pos + i);
> -#ifdef CONFIG_SND_DEBUG_ROM
> -		printk(KERN_DEBUG "ROM at 0x%06x = %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", bank_pos,
> -		       iwave[0], iwave[1], iwave[2], iwave[3],
> -		       iwave[4], iwave[5], iwave[6], iwave[7]);
> -#endif
>  		if (strncmp(iwave, "INTRWAVE", 8))
>  			continue;	/* first check */
>  		csum = 0;
>  		for (i = 0; i < sizeof(struct rom_hdr); i++)
>  			csum += snd_gf1_peek(gus, bank_pos + i);
> -#ifdef CONFIG_SND_DEBUG_ROM
> -		printk(KERN_DEBUG "ROM checksum = 0x%x (computed)\n", csum);
> -#endif
>  		if (csum != 0)
>  			continue;	/* not valid rom */
>  		gus->gf1.rom_banks++;
> -- 
> 1.7.0.4
>