On Thu, Oct 5, 2017 at 12:49 AM, Christophe LEROY <[email protected]> wrote: > > > 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.
Alright, sounds fine to me. Would this be okay? + select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if !PPC64 -Kees > > Christophe > > >> >> Cc: Benjamin Herrenschmidt <[email protected]> >> Cc: Paul Mackerras <[email protected]> >> Cc: Michael Ellerman <[email protected]> >> Cc: [email protected] >> Signed-off-by: Kees Cook <[email protected]> >> --- >> 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 >> > -- Kees Cook Pixel Security
