Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

PATCH Superseded Josh Triplett 3 participants 18 messages Jun 5, 2011 – Jun 7, 2011 Library code

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Josh Triplett

author

2011-06-05 21:02 UTC #0 lore raw

PATCH 1/1 Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.

Signed-off-by Josh Triplett <[email protected]>

---

Revised as requested by Ingo Molnar.

 init/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

init/Kconfig +1 -0

index ebafac4..5e482a3 100644
@@ -909,6 +909,7 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

Signature · 1 line

1.7.5.3

Frederic Weisbecker

2011-06-05 21:31 UTC #1 lore raw

Quoted 22 lines · Josh Triplett

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Signed-off-by Josh Triplett <[email protected]>
---
Revised as requested by Ingo Molnar.
 init/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
init/Kconfig +0 -0
index ebafac4..5e482a3 100644

init/Kconfig config ANON_INODES · line 912

Quoted 4 lines

init/Kconfig +1 -0

@@ -909,6 +909,7 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	select DEBUG_KERNEL

Please add a quick comment that explains the reason for that select. Because without that changelog, it's very non obvious.

Thanks.

Quoted 11 lines

init/Kconfig +0 -0

 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

Signature · 7 lines

1.7.5.3

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Josh Triplett

author

2011-06-06 01:24 UTC #2 lore raw

PATCH v2 1/1 Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Signed-off-by Josh Triplett <[email protected]>

---

v2: Add a comment explaining the select of DEBUG_KERNEL, as suggested by Frederic Weisbecker.

 init/Kconfig |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

init/Kconfig +2 -0

index ebafac4..48a173e 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+ 	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

Signature · 1 line

1.7.5.3

tip-bot for Josh Triplett

author

2011-06-06 22:07 UTC #3 lore raw

[tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Commit-ID:  f505c553dbe24b18a8590eb0eb5890a839acd0c3
Gitweb:     http://git.kernel.org/tip/f505c553dbe24b18a8590eb0eb5890a839acd0c3
Author:     Josh Triplett <[email protected]>
AuthorDate: Sun, 5 Jun 2011 18:23:58 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Tue, 7 Jun 2011 00:05:15 +0200

debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Signed-off-by Josh Triplett <[email protected]>

Acked-by Frederic Weisbecker <[email protected]>

Cc Sam Ravnborg <[email protected]>

Cc Linus Torvalds <[email protected]>

Link http://lkml.kernel.org/r/20110606012358.GA1909@leaf open here

Signed-off-by Ingo Molnar <[email protected]>

---
 init/Kconfig |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

init/Kconfig +2 -0

index ebafac4..14370d3 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

Ingo Molnar

2011-06-06 15:18 UTC #4 lore raw

In reply to Josh Triplett

Quoted 22 lines · Josh Triplett

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Signed-off-by Josh Triplett <[email protected]>
---
Revised as requested by Ingo Molnar.
 init/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
init/Kconfig +0 -0
index ebafac4..5e482a3 100644

init/Kconfig config ANON_INODES · line 915

Quoted 7 lines

init/Kconfig +1 -0

@@ -909,6 +909,7 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

So now that it's selected, mind removing the superfluous EXPERT bits from the Kconfig files that have it?

Thanks,

Ingo

Josh Triplett

author

2011-06-06 16:51 UTC #5 lore raw

PATCH v3 1/1 Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.

Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".) Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.

Signed-off-by Josh Triplett <[email protected]>

---

v3: Changed other debugging options to stop referencing EXPERT.

 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)

arch/tile/Kconfig.debug +1 -1

index ddbfc33..afc9cf3 100644
@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if DEBUG_KERNEL
 	default y
 	help
 	  Write kernel log output directly via the hypervisor console.

init/Kconfig +2 -0

index ebafac4..14370d3 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

lib/Kconfig.debug +3 -3

index dd373c8..b121413 100644
@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL
 	depends on BUG
 	depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \
 		   FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300 || TILE

@@ -766,8 +766,8 @@ config DEBUG_WRITECOUNT
 	  If unsure, say N.
 
 config DEBUG_MEMORY_INIT
-	bool "Debug memory initialisation" if EXPERT
-	default !EXPERT
+	bool "Debug memory initialisation" if DEBUG_KERNEL
+	default y
 	help
 	  Enable this for additional checks during memory initialisation.
 	  The sanity checks verify aspects of the VM such as the memory model

Signature · 1 line

1.7.5.3

Frederic Weisbecker

2011-06-06 18:16 UTC #6 lore raw

Quoted 11 lines · Josh Triplett

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.

Ok, so ideally this should have been done in two patches. They are both different logical changes that don't imply the same.

v2 was fine, and should be an independent change.

But some comment on what was added in this v3 below:

Quoted 23 lines

Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".) Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
---
v3: Changed other debugging options to stop referencing EXPERT.
 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)
arch/tile/Kconfig.debug +0 -0
index ddbfc33..afc9cf3 100644

arch/tile/Kconfig.debug menu "Kernel hacking" · line 7

Quoted 6 lines

arch/tile/Kconfig.debug +1 -1

@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if DEBUG_KERNEL
 	default y

I don't understand why early_printk is default y. But that's debatable, we may want to have any user able to run a raw vga console for debugging requests.

Either:

- if we consider it's very important and mandatory, let's keep it "if EXPERT" and default y.

- if we consider it's only used by kernel developers, it should be off by default and depend on DEBUG_KERNEL only.

Quoted 20 lines

arch/tile/Kconfig.debug +0 -0

 	help
 	  Write kernel log output directly via the hypervisor console.

init/Kconfig +2 -0

index ebafac4..14370d3 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

lib/Kconfig.debug +0 -0

index dd373c8..b121413 100644

lib/Kconfig.debug config DEBUG_HIGHMEM · line 697

Quoted 5 lines

lib/Kconfig.debug +1 -1

@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL

I believe this should not be changed, let keep it how it is, or change to "if EXPERT" because EXPERT selects DEBUG_KERNEL anyway.

There are no good reason to disable this option, except for some embedded system perhaps, so EXPERT still make sense here.

Thanks.

Josh Triplett

author

2011-06-06 18:39 UTC #7 lore raw

Quoted 10 lines · Frederic Weisbecker

Quoted 9 lines · Josh Triplett
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.

Quoted 5 lines

Quoted 2 lines
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Ok, so ideally this should have been done in two patches. They are both different logical changes that don't imply the same.

Fair enough; I'd considered whether to split this patch or not, and ended up with "not" on the theory that this seemed like a case of "fix an API and fix up the callers", but I can easily split it in v4.

Quoted 37 lines

v2 was fine, and should be an independent change.
But some comment on what was added in this v3 below:
Quoted 22 lines
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".) Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
---
v3: Changed other debugging options to stop referencing EXPERT.
 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)
arch/tile/Kconfig.debug +0 -0
index ddbfc33..afc9cf3 100644
arch/tile/Kconfig.debug menu "Kernel hacking" · line 7
Quoted 6 lines
arch/tile/Kconfig.debug +1 -1
@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if DEBUG_KERNEL
 	default y
I don't understand why early_printk is default y. But that's debatable, we may want to have any user able to run a raw vga console for debugging requests.

Quoted 7 lines

Either:
- if we consider it's very important and mandatory, let's keep it "if EXPERT" and default y.
- if we consider it's only used by kernel developers, it should be off by default and depend on DEBUG_KERNEL only.

Note that this change occurs in arch/tile/Kconfig.debug; you'd have to ask the Tile architecture developers about the rationale there. For the purposes of this change, I'd prefer not to make any semantic change there. Based on your explanation, that probably means I should change it to "if EXPERT" rather than "if DEBUG_KERNEL", keeping the current behavior of "only experts can turn this off". I'll do that in v4.

Quoted 12 lines

lib/Kconfig.debug config DEBUG_HIGHMEM · line 697
Quoted 8 lines
lib/Kconfig.debug +1 -1
@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL
I believe this should not be changed, let keep it how it is, or change to "if EXPERT" because EXPERT selects DEBUG_KERNEL anyway.

Quoted 2 lines

There are no good reason to disable this option, except for some embedded system perhaps, so EXPERT still make sense here.

I guess this matches the rationale above for tile's EARLY_PRINTK; I'll use "if EXPERT" to preserve the behavior of "only experts can turn this off". To me it seems equivalent to any other debug option, and I don't really see the harm in allowing users to turn it off if they turned on DEBUG_KERNEL, but nevertheless this patch shouldn't make that kind of semantic change.

- Josh Triplett

Frederic Weisbecker

2011-06-06 21:34 UTC #8 lore raw

Quoted 14 lines · Josh Triplett

Quoted 13 lines · Frederic Weisbecker
Quoted 11 lines · Josh Triplett
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.

Quoted 6 lines

Quoted 2 lines
Ok, so ideally this should have been done in two patches. They are both different logical changes that don't imply the same.
Fair enough; I'd considered whether to split this patch or not, and ended up with "not" on the theory that this seemed like a case of "fix an API and fix up the callers", but I can easily split it in v4.

You haven't just fixed the API and propagated to the callers accordingly. What you did is to fix the API and also completely change the behaviour of the callers.

You have changed EXPERT to imply DEBUG_KERNEL.
You'd have fixed the callers accordingly if you only changed "depend on EXPERT && DEBUG_KERNEL" into "depend on EXPERT" in the callers, because if EXPERT => DEBUG_KERNEL then (EXPERT && DEBUG_KERNEL) == EXPERT. Thus it would have fit into the same logic and gathering the whole into a single patch would have made sense (although that's debatable, I would have cut that personally, but we don't care at that level).

Now changing callers that "depend on EXPERT && DEBUG_KERNEL" to "depend on DEBUG_KERNEL" subscribes to a completely different logical change. It has actually even nothing to deal with the previous change. You can make that behaviour change even without having EXPERT => DEBUG_KERNEL.

So not only you gathered two different logical changes into a same patch, but the two things even hardly have any connection together.

Quoted 45 lines

Quoted 37 lines
v2 was fine, and should be an independent change.
But some comment on what was added in this v3 below:
Quoted 22 lines
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".) Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
---
v3: Changed other debugging options to stop referencing EXPERT.
 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)
arch/tile/Kconfig.debug +0 -0
index ddbfc33..afc9cf3 100644
arch/tile/Kconfig.debug menu "Kernel hacking" · line 7
Quoted 6 lines
arch/tile/Kconfig.debug +1 -1
@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if DEBUG_KERNEL
 	default y
I don't understand why early_printk is default y. But that's debatable, we may want to have any user able to run a raw vga console for debugging requests.
Quoted 7 lines
Either:
- if we consider it's very important and mandatory, let's keep it "if EXPERT" and default y.
- if we consider it's only used by kernel developers, it should be off by default and depend on DEBUG_KERNEL only.

Quoted 6 lines

Note that this change occurs in arch/tile/Kconfig.debug; you'd have to ask the Tile architecture developers about the rationale there. For the purposes of this change, I'd prefer not to make any semantic change there. Based on your explanation, that probably means I should change it to "if EXPERT" rather than "if DEBUG_KERNEL", keeping the current behavior of "only experts can turn this off". I'll do that in v4.

Ah it's in tile! I read that part too quickly, sorry. Yeah let them deal with that and only have "depend on EXPERT"

Quoted 12 lines

Quoted 12 lines
lib/Kconfig.debug config DEBUG_HIGHMEM · line 697
Quoted 8 lines
lib/Kconfig.debug +1 -1
@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL
I believe this should not be changed, let keep it how it is, or change to "if EXPERT" because EXPERT selects DEBUG_KERNEL anyway.

Quoted 6 lines

Quoted 2 lines
There are no good reason to disable this option, except for some embedded system perhaps, so EXPERT still make sense here.
I guess this matches the rationale above for tile's EARLY_PRINTK; I'll use "if EXPERT" to preserve the behavior of "only experts can turn this off".

Cool.

Quoted 4 lines

To me it seems equivalent to any other debug option, and I don't really see the harm in allowing users to turn it off if they turned on DEBUG_KERNEL, but nevertheless this patch shouldn't make that kind of semantic change.

It's not equivalent to other kernel debug options because unlike most other debug options we don't want only kernel developers to enable it, we want everyone to enable it.

If you let this option to be easily turned off, people may disable it by mistake and then developers will suddenly receive useless bug reports, which can be a frustrating experience.

There is no good reason to disable it except in some particular embedded cases I guess.

Ingo Molnar

2011-06-06 22:02 UTC #9 lore raw

Quoted 18 lines · Frederic Weisbecker

Quoted 17 lines · Josh Triplett
Quoted 15 lines · Frederic Weisbecker
Quoted 11 lines · Josh Triplett
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Ok, so ideally this should have been done in two patches. They are both different logical changes that don't imply the same.

Quoted 8 lines

Quoted 3 lines
Fair enough; I'd considered whether to split this patch or not, and ended up with "not" on the theory that this seemed like a case of "fix an API and fix up the callers", but I can easily split it in v4.
You haven't just fixed the API and propagated to the callers accordingly. What you did is to fix the API and also completely change the behaviour of the callers.
You have changed EXPERT to imply DEBUG_KERNEL.

yes, i suggested that, because it leads to a more maintainable (EXPERT noise free) DEBUG_KERNEL Kconfig section.

Quoted 7 lines

You'd have fixed the callers accordingly if you only changed "depend on EXPERT && DEBUG_KERNEL" into "depend on EXPERT" in the callers, because if EXPERT => DEBUG_KERNEL then (EXPERT && DEBUG_KERNEL) == EXPERT. Thus it would have fit into the same logic and gathering the whole into a single patch would have made sense (although that's debatable, I would have cut that personally, but we don't care at that level).

Hm, that's my fault - i missed that.

Thanks,

Ingo

Josh Triplett

author

2011-06-06 22:08 UTC #10 lore raw

PATCH v4 1/1 Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

In reply to Josh Triplett

Since EXPERT now implies DEBUG_KERNEL, change debugging options that reference DEBUG_KERNEL && EXPERT to just reference EXPERT.

Signed-off-by Josh Triplett <[email protected]>

---
v4: Avoid semantic changes, by changing DEBUG_KERNEL && EXPERT to EXPERT rather than to DEBUG_KERNEL. This avoids exposing debug options that only experts should turn off, such as DEBUG_BUGVERBOSE.

A subsequent patch should probably go through and change the various "default !EXPERT" lines to "default y", since enabling CONFIG_EXPERT should not directly change anything.

 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

arch/tile/Kconfig.debug +1 -1

index ddbfc33..1d31246 100644
@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if EXPERT
 	default y
 	help
 	  Write kernel log output directly via the hypervisor console.

init/Kconfig +2 -0

index ebafac4..14370d3 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

lib/Kconfig.debug +1 -1

index dd373c8..9a00361 100644
@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if EXPERT
 	depends on BUG
 	depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \
 		   FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300 || TILE

Signature · 1 line

1.7.5.3

Frederic Weisbecker

Acked-by on v4 1/1

2011-06-06 23:48 UTC #11 lore raw

Quoted 9 lines · Josh Triplett

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA. Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.

Quoted 4 lines

Since EXPERT now implies DEBUG_KERNEL, change debugging options that reference DEBUG_KERNEL && EXPERT to just reference EXPERT.
Signed-off-by Josh Triplett <[email protected]>

Acked-by Frederic Weisbecker <[email protected]>

Ingo, is it possible to zap the old one from the tree and apply this one instead?

Or may be Josh can send an incremental patch instead (I just feel bad in advance to ask him for a v5 :)

tip-bot for Josh Triplett

author

2011-06-06 21:40 UTC #12 lore raw

[tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

In reply to Josh Triplett

Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200

debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.

Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.

Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.

Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.

Signed-off-by Josh Triplett <[email protected]>

Acked-by Frederic Weisbecker <[email protected]>

Cc Sam Ravnborg <[email protected]>

Cc Linus Torvalds <[email protected]>

Link http://lkml.kernel.org/r/20110606165130.GA1844@leaf open here

Signed-off-by Ingo Molnar <[email protected]>

---
 arch/tile/Kconfig.debug |    2 +-
 init/Kconfig            |    2 ++
 lib/Kconfig.debug       |    6 +++---
 3 files changed, 6 insertions(+), 4 deletions(-)

arch/tile/Kconfig.debug +1 -1

index ddbfc33..afc9cf3 100644
@@ -3,7 +3,7 @@ menu "Kernel hacking"
 source "lib/Kconfig.debug"
 
 config EARLY_PRINTK
-	bool "Early printk" if EXPERT && DEBUG_KERNEL
+	bool "Early printk" if DEBUG_KERNEL
 	default y
 	help
 	  Write kernel log output directly via the hypervisor console.

init/Kconfig +2 -0

index ebafac4..14370d3 100644
@@ -909,6 +909,8 @@ config ANON_INODES
 
 menuconfig EXPERT
 	bool "Configure standard kernel features (expert users)"
+	# Unhide debug options, to make the on-by-default options visible
+	select DEBUG_KERNEL
 	help
 	  This option allows certain base kernel options and settings
           to be disabled or tweaked. This is for specialized

lib/Kconfig.debug +3 -3

index dd373c8..b121413 100644
@@ -694,7 +694,7 @@ config DEBUG_HIGHMEM
 	  Disable for production systems.
 
 config DEBUG_BUGVERBOSE
-	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL
 	depends on BUG
 	depends on ARM || AVR32 || M32R || M68K || SPARC32 || SPARC64 || \
 		   FRV || SUPERH || GENERIC_BUG || BLACKFIN || MN10300 || TILE

@@ -766,8 +766,8 @@ config DEBUG_WRITECOUNT
 	  If unsure, say N.
 
 config DEBUG_MEMORY_INIT
-	bool "Debug memory initialisation" if EXPERT
-	default !EXPERT
+	bool "Debug memory initialisation" if DEBUG_KERNEL
+	default y
 	help
 	  Enable this for additional checks during memory initialisation.
 	  The sanity checks verify aspects of the VM such as the memory model

Frederic Weisbecker

2011-06-06 21:45 UTC #13 lore raw

Re: [tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Quoted 27 lines · tip-bot for Josh Triplett

Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200
debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.
Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".)

Quoted 6 lines

Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
Acked-by Frederic Weisbecker <[email protected]>

No, Nacked actually. I'm fine with the v2 that only changed the EXPERT config to imply DEBUG_KERNEL. But all the other changes here need to be revised, as I outlined in the thread.

Josh Triplett

author

2011-06-06 22:09 UTC #14 lore raw

Re: [tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Quoted 32 lines · Frederic Weisbecker

Quoted 31 lines · tip-bot for Josh Triplett
Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200
debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.
Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".)
Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.

Quoted 6 lines

Quoted 2 lines
Signed-off-by Josh Triplett <[email protected]>
Acked-by Frederic Weisbecker <[email protected]>
No, Nacked actually. I'm fine with the v2 that only changed the EXPERT config to imply DEBUG_KERNEL. But all the other changes here need to be revised, as I outlined in the thread.

Fixed in v4; please replace the patch in tip with that.

- Josh Triplett

Ingo Molnar

2011-06-07 10:19 UTC #15 lore raw

Re: [tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Quoted 33 lines · Josh Triplett

Quoted 32 lines · Frederic Weisbecker
Quoted 31 lines · tip-bot for Josh Triplett
Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200
debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.
Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".)
Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.

Quoted 8 lines

Quoted 6 lines
Quoted 2 lines
Signed-off-by Josh Triplett <[email protected]>
Acked-by Frederic Weisbecker <[email protected]>
No, Nacked actually. I'm fine with the v2 that only changed the EXPERT config to imply DEBUG_KERNEL. But all the other changes here need to be revised, as I outlined in the thread.
Fixed in v4; please replace the patch in tip with that.

i applied the much simpler v2 twoliner version instead.

Thanks,

Ingo

Josh Triplett

author

2011-06-07 15:34 UTC #16 lore raw

Re: [tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Quoted 39 lines · Ingo Molnar

Quoted 36 lines · Josh Triplett
Quoted 35 lines · Frederic Weisbecker
Quoted 33 lines · tip-bot for Josh Triplett
Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200
debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.
Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".)
Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
Acked-by Frederic Weisbecker <[email protected]>

Quoted 7 lines

Quoted 5 lines
Quoted 3 lines
No, Nacked actually. I'm fine with the v2 that only changed the EXPERT config to imply DEBUG_KERNEL. But all the other changes here need to be revised, as I outlined in the thread.
Fixed in v4; please replace the patch in tip with that.
i applied the much simpler v2 twoliner version instead.

OK...

So, should I prepare a separate patch which changes the instances of DEBUG_KERNEL && EXPERT, or just leave them?

- Josh Triplett

Ingo Molnar

2011-06-07 18:04 UTC #17 lore raw

Re: [tip:core/debug] debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options

Quoted 44 lines · Josh Triplett

Quoted 43 lines · Ingo Molnar
Quoted 40 lines · Josh Triplett
Quoted 38 lines · Frederic Weisbecker
Quoted 27 lines · tip-bot for Josh Triplett
Commit-ID:  2458073da04571182748aa4289630dca52ba63cc
Gitweb:     http://git.kernel.org/tip/2458073da04571182748aa4289630dca52ba63cc
Author:     Josh Triplett <[email protected]>
AuthorDate: Mon, 6 Jun 2011 09:51:30 -0700
Committer:  Ingo Molnar <[email protected]>
CommitDate: Mon, 6 Jun 2011 19:30:01 +0200
debug: Make CONFIG_EXPERT select CONFIG_DEBUG_KERNEL to unhide debug options
Several debugging options currently default to y, such as CONFIG_DEBUG_BUGVERBOSE and CONFIG_DEBUG_RODATA.
Embedded users might want to turn those options off to save space; however, turning them off requires turning on CONFIG_DEBUG_KERNEL to unhide them. Since CONFIG_DEBUG_KERNEL exists specifically to unhide debugging options, and CONFIG_EXPERT exists specifically to unhide options potentially needed by experts and/or embedded users, make CONFIG_EXPERT automatically imply CONFIG_DEBUG_KERNEL.
Change various debugging options to only reference DEBUG_KERNEL, not EXPERT.
Note that DEBUG_MEMORY_INIT defaulted to !EXPERT, which seemed wrong, since EXPERT should not directly affect anything except the availability of other options. (And EXPERT definitely shouldn't mean "implicitly turn off default safety features".)
Quoted 6 lines
Change it to default to y, which means that turning on EXPERT does not automatically disable it, but will provide the option to disable it.
Signed-off-by Josh Triplett <[email protected]>
Acked-by Frederic Weisbecker <[email protected]>
No, Nacked actually. I'm fine with the v2 that only changed the EXPERT config to imply DEBUG_KERNEL. But all the other changes here need to be revised, as I outlined in the thread.

Quoted 8 lines

Quoted 3 lines
Quoted 1 line
Fixed in v4; please replace the patch in tip with that.
i applied the much simpler v2 twoliner version instead.
OK...
So, should I prepare a separate patch which changes the instances of DEBUG_KERNEL && EXPERT, or just leave them?

Yeah, would be nice to send a separate patch for that - 'DEBUG_KERNEL && EXPERT' is equivalent to EXPERT now, right?

Thanks,

Ingo