Le 05/10/2017 à 05:45, Kees Cook a écrit :
When available, CONFIG_KERNEL_RWX should be default-enabled.
On PPC32, this option implies deactivating BATs and/or LTLB mapping of
the linear kernel address space, hence a significant performance
degradation.
So at least on PPC32, it should remain unselected by default.
Christophe
Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org>
Cc: Paul Mackerras <pau...@samba.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: linuxppc-...@lists.ozlabs.org
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
arch/powerpc/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 809c468edab1..9a549bbfc278 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -178,6 +178,7 @@ config PPC
select HAVE_ARCH_TRACEHOOK
select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) &&
!RELOCATABLE && !HIBERNATION)
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
+ select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
select HAVE_CBPF_JIT if !PPC64
select HAVE_CONTEXT_TRACKING if PPC64
select HAVE_DEBUG_KMEMLEAK
