[PATCH] mm: remove bad_range

bad_range is supposed to be a temporary check.  It would be a pity to throw it
out.  Make it depend on CONFIG_DEBUG_VM instead.

CONFIG_HOLES_IN_ZONE systems were relying on this to check pfn_valid in the
page allocator.  Add that to page_is_buddy instead.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 156822e..1cedc23 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -172,7 +172,8 @@
 	bool "Debug VM"
 	depends on DEBUG_KERNEL
 	help
-	  Enable this to debug the virtual-memory system.
+	  Enable this to turn on extended checks in the virtual-memory system
+          that may impact performance.
 
 	  If unsure, say N.