kmemcheck: add the kmemcheck core

General description: kmemcheck is a patch to the linux kernel that
detects use of uninitialized memory. It does this by trapping every
read and write to memory that was allocated dynamically (e.g. using
kmalloc()). If a memory address is read that has not previously been
written to, a message is printed to the kernel log.

Thanks to Andi Kleen for the set_memory_4k() solution.

Andrew Morton suggested documenting the shadow member of struct page.

Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

[export kmemcheck_mark_initialized]
[build fix for setup_max_cpus]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

[rebased for mainline inclusion]
Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index edbd0ca62067..1b68659c41b4 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile
@@ -81,6 +81,11 @@ ifdef CONFIG_CC_STACKPROTECTOR
         endif
 endif
 
+# Don't unroll struct assignments with kmemcheck enabled
+ifeq ($(CONFIG_KMEMCHECK),y)
+        KBUILD_CFLAGS += $(call cc-option,-fno-builtin-memcpy)
+endif
+
 # Stackpointer is addressed different for 32 bit and 64 bit x86
 sp-$(CONFIG_X86_32) := esp
 sp-$(CONFIG_X86_64) := rsp