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authorAkinobu Mita <akinobu.mita@gmail.com>2009-03-31 15:23:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-01 08:59:13 -0700
commit6a11f75b6a17b5d9ac5025f8d048382fd1f47377 (patch)
treea3415cd897823975b927f89a233d2703bf97ba2b /arch/x86/Kconfig.debug
parent610a77e04a8d9fe8764dc484e2182fa251ce1cc2 (diff)
generic debug pagealloc
CONFIG_DEBUG_PAGEALLOC is now supported by x86, powerpc, sparc64, and s390. This patch implements it for the rest of the architectures by filling the pages with poison byte patterns after free_pages() and verifying the poison patterns before alloc_pages(). This generic one cannot detect invalid page accesses immediately but invalid read access may cause invalid dereference by poisoned memory and invalid write access can be detected after a long delay. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/Kconfig.debug')
-rw-r--r--arch/x86/Kconfig.debug1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index fdb45df608b..a345cb5447a 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -75,6 +75,7 @@ config DEBUG_STACK_USAGE
config DEBUG_PAGEALLOC
bool "Debug page memory allocations"
depends on DEBUG_KERNEL
+ depends on 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