|  | config DEBUG_PAGEALLOC | 
|  | bool "Debug page memory allocations" | 
|  | 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 | 
|  | select WANT_PAGE_DEBUG_FLAGS |