On Wed, Feb 28, 2018 at 4:39 PM, Segher Boessenkool <seg...@kernel.crashing.org> wrote: > On Wed, Feb 28, 2018 at 04:15:23PM -0800, Kees Cook wrote: >> On Wed, Feb 28, 2018 at 3:23 PM, Segher Boessenkool >> <seg...@kernel.crashing.org> wrote: >> > I'm trying to figure out how to get that file to build at all :-) > >> $ CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc make wii_defconfig >> $ for i in CONFIG_STRICT_KERNEL_RWX \ >> CONFIG_DEBUG_KERNEL \ >> CONFIG_DEBUG_RODATA_TEST ; do >> CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc ./scripts/config -e $i >> done > > I use ppc6xx_defconfig normally; I had to disable CONFIG_HIBERNATION > as well. > > Without the new flag, rodata_test_data ends up in .sdata in the object > file and in .data in vmlinux. > > Adding > > === > diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile > index ccd2556..31b9613 100644 > --- a/arch/powerpc/Makefile > +++ b/arch/powerpc/Makefile > @@ -143,6 +143,8 @@ CFLAGS-$(CONFIG_PPC64) += $(call > cc-option,-mcmodel=med > CFLAGS-$(CONFIG_PPC64) += $(call cc-option,-mno-pointers-to-nested-functions) > CFLAGS-$(CONFIG_PPC32) := -ffixed-r2 $(MULTIPLEWORD) > > +CFLAGS-$(CONFIG_PPC32) += $(call cc-option,-mno-readonly-in-sdata) > + > ifeq ($(CONFIG_PPC_BOOK3S_64),y) > CFLAGS-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=power7,-mtune=power4) > CFLAGS-$(CONFIG_GENERIC_CPU) += -mcpu=power4 > === > > it ends up in .rodata in both.
Excellent! That's perfect. :) > It would be nice to have a more comprehensive test, but this will do; I'll > commit it tomorrow (will resend, with doc and changelog and all that). Thank you! Do you want to send the Makefile fix upstream too, or should I route that? -Kees -- Kees Cook Pixel Security
