[PATCH 13/14] kconfig: loop as long as we changed some symbols in randconfig

From: Yann E. MORIN
Date: Tue Jun 18 2013 - 18:46:20 EST


From: "Yann E. MORIN" <yann.morin.1998@xxxxxxx>

Because of choice-in-a-choice constructs, it can happen that not all
symbols are assigned a value during randconfig, leading in rare cases
to this situation:

---8<--- choice-in-choice.in
choice
bool "A/B/C"
config A
bool "A"

config B
bool "B"
if B
choice
bool "E/F"
config E
bool "E"
config F
bool "F"
endchoice
endif # B

config C
bool "C"
endchoice
---8<---

$ ./scripts/kconfig/conf --randconfig choice-in-choice.in
[--SNIP--]
$ ./scripts/kconfig/conf --silentoldconfig choice-in-choice.in </dev/null
[--SNIP--]
A/B/C
1. A (A)
> 2. B (B)
3. C (C)
choice[1-3]: 2
E/F
> 1. E (E) (NEW)
2. F (F) (NEW)
choice[1-2]: aborted!

Console input/output is redirected. Run 'make oldconfig' to update
configuration.

Fix this by looping in randconfig for as long as some symbol gets assigned
a value.

Note: this was spotted with the USB EHCI Debug Device Gadget (USB_G_DBGP),
which uses this choice-in-a-choice construct, and exhibits this problem.
The example above is just a stripped-down minimalist test-case.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@xxxxxxx>
---
scripts/kconfig/conf.c | 3 ++-
scripts/kconfig/confdata.c | 18 ++++++++++++++----
scripts/kconfig/lkc.h | 2 +-
3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index 38616c1..d19944f 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -654,7 +654,8 @@ int main(int ac, char **av)
conf_set_all_new_symbols(def_default);
break;
case randconfig:
- conf_set_all_new_symbols(def_random);
+ /* Really nothing to do in this loop */
+ while (conf_set_all_new_symbols(def_random)) ;
break;
case defconfig:
conf_set_all_new_symbols(def_default);
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index d36bc1f..c55c227 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -1040,7 +1040,7 @@ void conf_set_changed_callback(void (*fn)(void))
conf_changed_callback = fn;
}

-static void randomize_choice_values(struct symbol *csym)
+static bool randomize_choice_values(struct symbol *csym)
{
struct property *prop;
struct symbol *sym;
@@ -1053,7 +1053,7 @@ static void randomize_choice_values(struct symbol *csym)
* In both cases stop.
*/
if (csym->curr.tri != yes)
- return;
+ return false;

prop = sym_get_choice_prop(csym);

@@ -1084,6 +1084,8 @@ static void randomize_choice_values(struct symbol *csym)
csym->flags |= SYMBOL_DEF_USER;
/* clear VALID to get value calculated */
csym->flags &= ~(SYMBOL_VALID);
+
+ return true;
}

void set_all_choice_values(struct symbol *csym)
@@ -1106,7 +1108,7 @@ void set_all_choice_values(struct symbol *csym)
csym->flags &= ~(SYMBOL_VALID | SYMBOL_NEED_SET_CHOICE_VALUES);
}

-void conf_set_all_new_symbols(enum conf_def_mode mode)
+bool conf_set_all_new_symbols(enum conf_def_mode mode)
{
struct symbol *sym, *csym;
int i, cnt, pby, pty, ptm; /* pby: probability of boolean = y
@@ -1154,6 +1156,7 @@ void conf_set_all_new_symbols(enum conf_def_mode mode)
exit( 1 );
}
}
+ bool has_changed = false;

for_all_symbols(i, sym) {
if (sym_has_value(sym) || (sym->flags & SYMBOL_VALID))
@@ -1161,6 +1164,7 @@ void conf_set_all_new_symbols(enum conf_def_mode mode)
switch (sym_get_type(sym)) {
case S_BOOLEAN:
case S_TRISTATE:
+ has_changed = true;
switch (mode) {
case def_yes:
sym->def[S_DEF_USER].tri = yes;
@@ -1219,6 +1223,12 @@ void conf_set_all_new_symbols(enum conf_def_mode mode)

sym_calc_value(csym);
if (mode == def_random)
- randomize_choice_values(csym);
+ has_changed = randomize_choice_values(csym);
+ else {
+ set_all_choice_values(csym);
+ has_changed = true;
+ }
}
+
+ return has_changed;
}
diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h
index 0c8d419..09f4edf 100644
--- a/scripts/kconfig/lkc.h
+++ b/scripts/kconfig/lkc.h
@@ -86,7 +86,7 @@ const char *conf_get_autoconfig_name(void);
char *conf_get_default_confname(void);
void sym_set_change_count(int count);
void sym_add_change_count(int count);
-void conf_set_all_new_symbols(enum conf_def_mode mode);
+bool conf_set_all_new_symbols(enum conf_def_mode mode);
void set_all_choice_values(struct symbol *csym);

struct conf_printer {
--
1.8.1.2

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