[S390] DEBUG_PAGEALLOC support for s390.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug
index 2283933..4599fa0 100644
--- a/arch/s390/Kconfig.debug
+++ b/arch/s390/Kconfig.debug
@@ -6,4 +6,12 @@
 
 source "lib/Kconfig.debug"
 
+config DEBUG_PAGEALLOC
+	bool "Debug page memory allocations"
+	depends on DEBUG_KERNEL
+	help
+	  Unmap pages from the kernel linear mapping after free_pages().
+	  This results in a slowdown, but helps to find certain types of
+	  memory corruptions.
+
 endmenu