[PATCH] x86: boot: Remove ancient dead code

[PATCH] x86: boot: Remove ancient dead code

[Paul Bolle]

Release v1.3.82 wrapped a few lines of code in an "#ifdef
SAFE_RESET_DISK_CONTROLLER" and "#endif" pair. Since
SAFE_RESET_DISK_CONTROLLER was never defined anywhere that was basically
a verbose "#ifdef 0" and "#endif" pair. These dead lines have been in
the tree for sixteen years but now the time has come to remove them.

I guess the main lesson here is that if you want your dead code in the
tree for a very long time you'd better be creative. A plain old "#ifdef
0" and "#endif" pair just doesn't cut it!

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Link: https://lkml.org/lkml/1996/3/30/38
Cc: Jeff Epler <jepler@inetnebr.com>
---
 arch/x86/boot/header.S |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index efe5acf..9b9c647 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -406,13 +406,6 @@ init_size:		.long INIT_SIZE		# kernel initialization size
 
 	.section ".entrytext", "ax"
 start_of_setup:
-#ifdef SAFE_RESET_DISK_CONTROLLER
-# Reset the disk controller.
-	movw	$0x0000, %ax		# Reset disk controller
-	movb	$0x80, %dl		# All disks
-	int	$0x13
-#endif
-
 # Force %es = %ds
 	movw	%ds, %ax
 	movw	%ax, %es
-- 
1.7.7.6

Re: [PATCH] x86: boot: Remove ancient dead code

[Jesper Juhl]

On Thu, 21 Jun 2012, Paul Bolle wrote:

> Release v1.3.82 wrapped a few lines of code in an "#ifdef
> SAFE_RESET_DISK_CONTROLLER" and "#endif" pair. Since
> SAFE_RESET_DISK_CONTROLLER was never defined anywhere that was basically
> a verbose "#ifdef 0" and "#endif" pair. These dead lines have been in
> the tree for sixteen years but now the time has come to remove them.
> 
> I guess the main lesson here is that if you want your dead code in the
> tree for a very long time you'd better be creative. A plain old "#ifdef
> 0" and "#endif" pair just doesn't cut it!
> 
> Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
> Link: https://lkml.org/lkml/1996/3/30/38
> Cc: Jeff Epler <jepler@inetnebr.com>
> ---
>  arch/x86/boot/header.S |    7 -------
>  1 files changed, 0 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
> index efe5acf..9b9c647 100644
> --- a/arch/x86/boot/header.S
> +++ b/arch/x86/boot/header.S
> @@ -406,13 +406,6 @@ init_size:		.long INIT_SIZE		# kernel initialization size
>  
>  	.section ".entrytext", "ax"
>  start_of_setup:
> -#ifdef SAFE_RESET_DISK_CONTROLLER
> -# Reset the disk controller.
> -	movw	$0x0000, %ax		# Reset disk controller
> -	movb	$0x80, %dl		# All disks
> -	int	$0x13
> -#endif
> -
>  # Force %es = %ds
>  	movw	%ds, %ax
>  	movw	%ax, %es
> 
Looks good to me.
Not that I have much knowledge of the code, but I did dig the history a 
bit and yes, this looks like long dead stuff that should just go away.

Acked-by: Jesper Juhl <jj@chaosbits.net>


-- 
Jesper Juhl <jj@chaosbits.net>       http://www.chaosbits.net/
Don't top-post http://www.catb.org/jargon/html/T/top-post.html
Plain text mails only, please.

Re: [PATCH] x86: boot: Remove ancient dead code

[Jeff Epler]

I hope you didn't spend too much time tracking me down just to Cc me on
this proposed change.

Unfortunately, I no longer have access to the hardware that I reported
the problem on.  :-P  Anyway,

Acked-by: Jeff Epler <jepler@unpythonic.net>

Jeff

[tip:x86/cleanups] x86, boot: Remove ancient, unconditionally #ifdef'd out dead code

[tip-bot for Paul Bolle]

Commit-ID:  e5a7286b5f1b0b5beb97275f2152bf10c4aa4204
Gitweb:     http://git.kernel.org/tip/e5a7286b5f1b0b5beb97275f2152bf10c4aa4204
Author:     Paul Bolle <pebolle@tiscali.nl>
AuthorDate: Thu, 21 Jun 2012 00:16:29 +0200
Committer:  H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 20 Jun 2012 17:28:56 -0700

x86, boot: Remove ancient, unconditionally #ifdef'd out dead code

Release v1.3.82 wrapped a few lines of code in an "#ifdef
SAFE_RESET_DISK_CONTROLLER" and "#endif" pair. Since
SAFE_RESET_DISK_CONTROLLER was never defined anywhere that was basically
a verbose "#ifdef 0" and "#endif" pair. These dead lines have been in
the tree for sixteen years but now the time has come to remove them.

I guess the main lesson here is that if you want your dead code in the
tree for a very long time you'd better be creative. A plain old "#ifdef
0" and "#endif" pair just doesn't cut it!

See: http://lkml.kernel.org/r/199603301718.LAA00178@craie.inetnebr.com

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Link: http://lkml.kernel.org/r/1340230589.1773.7.camel@x61.thuisdomein
Acked-by: Jeff Epler <jepler@unpythonic.net>
Acked-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
 arch/x86/boot/header.S |    7 -------
 1 files changed, 0 insertions(+), 7 deletions(-)

diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 8bbea6a..fde5bde 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -386,13 +386,6 @@ init_size:		.long INIT_SIZE		# kernel initialization size
 
 	.section ".entrytext", "ax"
 start_of_setup:
-#ifdef SAFE_RESET_DISK_CONTROLLER
-# Reset the disk controller.
-	movw	$0x0000, %ax		# Reset disk controller
-	movb	$0x80, %dl		# All disks
-	int	$0x13
-#endif
-
 # Force %es = %ds
 	movw	%ds, %ax
 	movw	%ax, %es

Re: [PATCH] x86: boot: Remove ancient dead code

[Ingo Molnar]

* Paul Bolle <pebolle@tiscali.nl> wrote:

> Release v1.3.82 wrapped a few lines of code in an "#ifdef
> SAFE_RESET_DISK_CONTROLLER" and "#endif" pair. Since
> SAFE_RESET_DISK_CONTROLLER was never defined anywhere that was basically
> a verbose "#ifdef 0" and "#endif" pair. These dead lines have been in
> the tree for sixteen years but now the time has come to remove them.
> 
> I guess the main lesson here is that if you want your dead code in the
> tree for a very long time you'd better be creative. A plain old "#ifdef
> 0" and "#endif" pair just doesn't cut it!

and putting it into assembly code is also key to success!

Thanks,

	Ingo