kconfig: Make KCONFIG_ALLCONFIG work with randconfig.

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.

---

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

index a38787a..61a61df 100644
@@ -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:

index a195986..f5b4873 100644
@@ -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

Hi,

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

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

Look at how SYMBOL_DEF is used in confdata.c.

Simply add a test for is_new there.

bye, Roman

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.

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.

---

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

index a38787a..8d6f174 100644
@@ -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: