On 07/27/2015 07:40 PM, Catalin Marinas wrote:

On Fri, Jul 24, 2015 at 07:41:53PM +0300, Andrey Ryabinin wrote:

quoted

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b3a1a5d..6d6dd6f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig

@@ -255,11 +255,6 @@ config ARCH_SUPPORTS_OPTIMIZED_INLINING
 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 	def_bool y
 
-config KASAN_SHADOW_OFFSET
-	hex
-	depends on KASAN
-	default 0xdffffc0000000000
-
 config HAVE_INTEL_TXT
 	def_bool y
 	depends on INTEL_IOMMU && ACPI

diff --git a/arch/x86/Makefile b/arch/x86/Makefile
index 118e6de..c666989 100644
--- a/arch/x86/Makefile
+++ b/arch/x86/Makefile

@@ -39,6 +39,8 @@ ifdef CONFIG_X86_NEED_RELOCS
         LDFLAGS_vmlinux := --emit-relocs
 endif
 
+KASAN_SHADOW_OFFSET := 0xdffffc0000000000

To keep things simple for x86, can you not just define:

KASAN_SHADOW_OFFSET := $(CONFIG_KASAN_SHADOW_OFFSET)

or, even better, in scripts/Makefile.kasan:

KASAN_SHADOW_OFFSET ?= $(CONFIG_KASAN_SHADOW_OFFSET)

and set it under arch/arm64/Makefile only.

Yes, this much better.