mm: debug-pagealloc: fix kconfig dependency warning

Fix kconfig dependency warning to satisfy dependencies:

warning: (PAGE_POISONING) selects DEBUG_PAGEALLOC which has unmet
direct dependencies (DEBUG_KERNEL && ARCH_SUPPORTS_DEBUG_PAGEALLOC &&
(!HIBERNATION || !PPC && !SPARC) && !KMEMCHECK)

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index af7cfb4..8b1a477 100644 (file)
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -1,27 +1,24 @@
 config DEBUG_PAGEALLOC
        bool "Debug page memory allocations"
-       depends on DEBUG_KERNEL && ARCH_SUPPORTS_DEBUG_PAGEALLOC
-       depends on !HIBERNATION || !PPC && !SPARC
+       depends on DEBUG_KERNEL
+       depends on !HIBERNATION || ARCH_SUPPORTS_DEBUG_PAGEALLOC && !PPC && !SPARC
        depends on !KMEMCHECK
+       select PAGE_POISONING if !ARCH_SUPPORTS_DEBUG_PAGEALLOC
        ---help---
          Unmap pages from the kernel linear mapping after free_pages().
          This results in a large slowdown, but helps to find certain types
          of memory corruption.
 
+         For architectures which don't enable ARCH_SUPPORTS_DEBUG_PAGEALLOC,
+         fill the pages with poison patterns after free_pages() and verify
+         the patterns before alloc_pages().  Additionally,
+         this option cannot be enabled in combination with hibernation as
+         that would result in incorrect warnings of memory corruption after
+         a resume because free pages are not saved to the suspend image.
+
 config WANT_PAGE_DEBUG_FLAGS
        bool
 
 config PAGE_POISONING
-       bool "Debug page memory allocations"
-       depends on DEBUG_KERNEL && !ARCH_SUPPORTS_DEBUG_PAGEALLOC
-       depends on !HIBERNATION
-       select DEBUG_PAGEALLOC
+       bool
        select WANT_PAGE_DEBUG_FLAGS
-       ---help---
-          Fill the pages with poison patterns after free_pages() and verify
-          the patterns before alloc_pages(). This results in a large slowdown,
-          but helps to find certain types of memory corruption.
-
-          This option cannot be enabled in combination with hibernation as
-          that would result in incorrect warnings of memory corruption after
-          a resume because free pages are not saved to the suspend image.