diff options
| author | Akinobu Mita <akinobu.mita@gmail.com> | 2009-03-31 15:23:17 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-04-01 08:59:13 -0700 |
| commit | 6a11f75b6a17b5d9ac5025f8d048382fd1f47377 (patch) | |
| tree | a3415cd897823975b927f89a233d2703bf97ba2b /arch/s390 | |
| parent | 610a77e04a8d9fe8764dc484e2182fa251ce1cc2 (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/s390')
| -rw-r--r-- | arch/s390/Kconfig | 3 | ||||
| -rw-r--r-- | arch/s390/Kconfig.debug | 1 |
2 files changed, 4 insertions, 0 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 2a8af5e16345..dcb667c4375a 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -72,6 +72,9 @@ config PGSTE config VIRT_CPU_ACCOUNTING def_bool y +config ARCH_SUPPORTS_DEBUG_PAGEALLOC + def_bool y + mainmenu "Linux Kernel Configuration" config S390 diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug index 4599fa06bd82..7e297a3cde34 100644 --- a/arch/s390/Kconfig.debug +++ b/arch/s390/Kconfig.debug @@ -9,6 +9,7 @@ source "lib/Kconfig.debug" 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 slowdown, but helps to find certain types of |