| config PAGE_EXTENSION |
| bool "Extend memmap on extra space for more information on page" |
| ---help--- |
| Extend memmap on extra space for more information on page. This |
| could be used for debugging features that need to insert extra |
| field for every page. This extension enables us to save memory |
| by not allocating this extra memory according to boottime |
| configuration. |
| |
| 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_EXTENSION |
| 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 PAGE_POISONING |
| bool |
