[linux-2.6-block.git] / mm / Kconfig.debug

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
Commit	Line	Data
eefa864b JK	1	config PAGE_EXTENSION
	2	bool "Extend memmap on extra space for more information on page"
	3	---help---
	4	Extend memmap on extra space for more information on page. This
	5	could be used for debugging features that need to insert extra
	6	field for every page. This extension enables us to save memory
	7	by not allocating this extra memory according to boottime
	8	configuration.
	9
ee3b4290 AM	10	config DEBUG_PAGEALLOC
ee3b4290 AM	11	bool "Debug page memory allocations"
7bc32f6f AM	12	depends on DEBUG_KERNEL
7bc32f6f AM	13	depends on !HIBERNATION \|\| ARCH_SUPPORTS_DEBUG_PAGEALLOC && !PPC && !SPARC
7d46d9e6	14	depends on !KMEMCHECK
e30825f1	15	select PAGE_EXTENSION
7bc32f6f	16	select PAGE_POISONING if !ARCH_SUPPORTS_DEBUG_PAGEALLOC
ee3b4290 AM	17	---help---
	18	Unmap pages from the kernel linear mapping after free_pages().
	19	This results in a large slowdown, but helps to find certain types
22f8b458	20	of memory corruption.
ee3b4290	21
7bc32f6f AM	22	For architectures which don't enable ARCH_SUPPORTS_DEBUG_PAGEALLOC,
	23	fill the pages with poison patterns after free_pages() and verify
	24	the patterns before alloc_pages(). Additionally,
	25	this option cannot be enabled in combination with hibernation as
	26	that would result in incorrect warnings of memory corruption after
	27	a resume because free pages are not saved to the suspend image.
	28
6a11f75b	29	config PAGE_POISONING
7bc32f6f	30	bool