On Fri, Oct 6, 2017 at 6:03 AM, Kees Cook <keesc...@chromium.org> wrote: > When available, CONFIG_KERNEL_RWX should be default-enabled for PPC64. > On PPC32, there is a performance trade-off. > > Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> > Cc: Paul Mackerras <pau...@samba.org> > Cc: Michael Ellerman <m...@ellerman.id.au> > Cc: Christophe LEROY <christophe.le...@c-s.fr> > Cc: Balbir Singh <bsinghar...@gmail.com> > Cc: linuxppc-...@lists.ozlabs.org > Signed-off-by: Kees Cook <keesc...@chromium.org> > --- > v2: > - depend on PPC64, as noted by Christophe. > --- > arch/powerpc/Kconfig | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 809c468edab1..4315c9b2db4f 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 if PPC64
We usually have CONFIG_RELOCATABLE on - on most configs. Our STRICT RWX depends on !RELOCATABLE as you've seen. I have patches to fix STRICT_KERNEL_RWX on CONFIG_RELOCATABLE https://patchwork.ozlabs.org/patch/795744/ (I need to rebase this to use generic helpers we have to convert an mm,addr to pte) Aside, I also have set_memory_xx at https://patchwork.ozlabs.org/patch/796183/ (again I need to rebase them) I hope to get to them next week, hopefully Balbir Singh.
