[PATCH] kasan: only select SLUB_DEBUG with SYSFS=y

[Arnd Bergmann]

Building with KASAN and SLUB but without sysfs now results in a build-time error:

WARNING: unmet direct dependencies detected for SLUB_DEBUG
  Depends on [n]: SLUB [=y] && SYSFS [=n]
  Selected by [y]:
  - KASAN [=y] && HAVE_ARCH_KASAN [=y] && (SLUB [=y] || SLAB [=n] && !DEBUG_SLAB [=n]) && SLUB [=y]
mm/slub.c:4565:12: error: 'list_locations' defined but not used [-Werror=unused-function]
 static int list_locations(struct kmem_cache *s, char *buf,
            ^~~~~~~~~~~~~~
mm/slub.c:4406:13: error: 'validate_slab_cache' defined but not used [-Werror=unused-function]
 static long validate_slab_cache(struct kmem_cache *s)

This disallows that broken configuration in Kconfig.

Fixes: dd275caf4a0d ("kasan: depend on CONFIG_SLUB_DEBUG")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 lib/Kconfig.kasan | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index c253c1b46c6b..befb127507c0 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -5,7 +5,7 @@ if HAVE_ARCH_KASAN
 
 config KASAN
 	bool "KASan: runtime memory debugger"
-	depends on SLUB || (SLAB && !DEBUG_SLAB)
+	depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
 	select SLUB_DEBUG if SLUB
 	select CONSTRUCTORS
 	select STACKDEPOT
-- 
2.9.0