[PATCH] kconfig: Make KCONFIG_ALLCONFIG work with randconfig.

[PATCH] kconfig: Make KCONFIG_ALLCONFIG work with randconfig.

[Paul Mundt]

Adrian mentioned a few weeks ago that KCONFIG_ALLCONFIG is the way to
go to ensure that things like allyes/allmod/allnoconfig work with a
constrained set of symbols, with the implication that this holds
true for randconfig as well.

While allyes/mod/noconfigs do seem to work fine with KCONFIG_ALLCONFIG
provisions, randconfig tramples all over the provided values at perhaps
not surprisingly, random.

Debugging this a bit, there seemed to be two issues:

	- SYMBOL_DEF and SYMBOL_DEF_USER overlap, which made
	  def_sym->flags the same regardless of whether we came from an
	  KCONFIG_ALLCONFIG path or not.

	- clobbering of the fixed value in conf_choice() by way of
	  random() def assignment.

While I don't pretend to have any idea what I'm doing in Kconfig,
changing SYMBOL_DEF_USER to reuse the SYMBOL_DEF3 bit (and thereby
separating it from SYMBOL_DEF) in addition to checking the def_sym flag
before randomly assigning a new value ended up fixing things up.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

---

 scripts/kconfig/conf.c |    9 ++++++++-
 scripts/kconfig/expr.h |    3 +--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index a38787a..61a61df 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -374,7 +374,14 @@ static int conf_choice(struct menu *menu)
 				continue;
 			break;
 		case set_random:
-			def = (random() % cnt) + 1;
+			/*
+			 * Defined symbols need to be honoured even in
+			 * the randomization case, or else symbols set
+			 * via the KCONFIG_ALLCONFIG path are clobbered.
+			 *				- PFM.
+			 */
+			if (!(def_sym->flags & SYMBOL_DEF))
+				def = (random() % cnt) + 1;
 		case set_default:
 		case set_yes:
 		case set_mod:
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index a195986..f5b4873 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -95,9 +95,8 @@ struct symbol {
 #define SYMBOL_CHECKED		0x2000
 #define SYMBOL_WARNED		0x8000
 #define SYMBOL_DEF		0x10000
-#define SYMBOL_DEF_USER		0x10000
 #define SYMBOL_DEF_AUTO		0x20000
-#define SYMBOL_DEF3		0x40000
+#define SYMBOL_DEF_USER		0x40000
 #define SYMBOL_DEF4		0x80000
 
 #define SYMBOL_MAXLENGTH	256

Re: [PATCH] kconfig: Make KCONFIG_ALLCONFIG work with randconfig.

[Roman Zippel]

Hi,

On Wed, 28 Nov 2007, Paul Mundt wrote:

> Adrian mentioned a few weeks ago that KCONFIG_ALLCONFIG is the way to
> go to ensure that things like allyes/allmod/allnoconfig work with a
> constrained set of symbols, with the implication that this holds
> true for randconfig as well.

BTW another possibility is to use all{no,mod,yes,random,}.config.

> While allyes/mod/noconfigs do seem to work fine with KCONFIG_ALLCONFIG
> provisions, randconfig tramples all over the provided values at perhaps
> not surprisingly, random.

Please be careful with such broad statements, there is only an issue with 
choice values.

> Debugging this a bit, there seemed to be two issues:
> 
> 	- SYMBOL_DEF and SYMBOL_DEF_USER overlap, which made
> 	  def_sym->flags the same regardless of whether we came from an
> 	  KCONFIG_ALLCONFIG path or not.

Look at how SYMBOL_DEF is used in confdata.c.

> 	- clobbering of the fixed value in conf_choice() by way of
> 	  random() def assignment.

Simply add a test for is_new there.

bye, Roman

Re: [PATCH] kconfig: Make KCONFIG_ALLCONFIG work with randconfig.

[Paul Mundt]

On Wed, Nov 28, 2007 at 06:08:16PM +0100, Roman Zippel wrote:
> On Wed, 28 Nov 2007, Paul Mundt wrote:
> > While allyes/mod/noconfigs do seem to work fine with KCONFIG_ALLCONFIG
> > provisions, randconfig tramples all over the provided values at perhaps
> > not surprisingly, random.
> 
> Please be careful with such broad statements, there is only an issue with 
> choice values.
> 
Ok, I'll rephrase, '100% of the provided values I tested with were being
randomly clobbered'. Is that better? Broken is broken, whether it applies
to a small subset of symbols or not.

> > Debugging this a bit, there seemed to be two issues:
> > 
> > 	- SYMBOL_DEF and SYMBOL_DEF_USER overlap, which made
> > 	  def_sym->flags the same regardless of whether we came from an
> > 	  KCONFIG_ALLCONFIG path or not.
> 
> Look at how SYMBOL_DEF is used in confdata.c.
> 
Ah, ok. I was just trying to find something I could test that would be
different for the KCONFIG_ALLCONFIG path, but it seems like is_new is a
much cleaner solution for this, thanks for pointing it out!

Updated patch follows.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

---

 scripts/kconfig/conf.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index a38787a..8d6f174 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -374,7 +374,8 @@ static int conf_choice(struct menu *menu)
 				continue;
 			break;
 		case set_random:
-			def = (random() % cnt) + 1;
+			if (is_new)
+				def = (random() % cnt) + 1;
 		case set_default:
 		case set_yes:
 		case set_mod: