Messages in this thread | | | Subject | Re: [PATCH] powerpc: Default to enabling STRICT_KERNEL_RWX | From | Christophe LEROY <> | Date | Thu, 5 Oct 2017 09:49:06 +0200 |
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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 <benh@kernel.crashing.org> > Cc: Paul Mackerras <paulus@samba.org> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: linuxppc-dev@lists.ozlabs.org > Signed-off-by: Kees Cook <keescook@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 >
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