On Fri, Oct 21, 2016 at 5:16 AM, Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> wrote: > Debian started to build the gcc with --enable-default-pie by default so the > kernel build ends before it starts properly with: > |kernel/bounds.c:1:0: error: code model kernel does not support PIC mode > > Is this okay or do we want some kind of check to see if -fno-PIE is supported? > It is mentioned in the 4.4.7 gcc manpage is it is not *that* new :) > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> > --- > Makefile | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/Makefile b/Makefile > index bf6e44a421df..97296d66b586 100644 > --- a/Makefile > +++ b/Makefile > @@ -398,7 +398,7 @@ KBUILD_CPPFLAGS := -D__KERNEL__ > KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ > -fno-strict-aliasing -fno-common \ > -Werror-implicit-function-declaration \ > - -Wno-format-security \ > + -Wno-format-security -fno-PIE \ > -std=gnu89 > > KBUILD_AFLAGS_KERNEL := > -- > 2.9.3 > Hi, I ran into this when I upgraded to Ubuntu 16.10. Ubuntu kernel team has a patch posted for Ubuntu kernels. The patch talks about needing have this work for other architectures. I applied part of the change from the original Ubuntu patch - https://patchwork.ozlabs.org/patch/616621/ Anyway, the following worked for me on x86-64 - both 4.8.4 and 4.9 diff --git a/Makefile b/Makefile index 82a36ab..0a01ad1 100644 --- a/Makefile +++ b/Makefile @@ -651,6 +651,11 @@ ifneq ($(CONFIG_FRAME_WARN),0) KBUILD_CFLAGS += $(call cc-option,-Wframe-larger-than=${CONFIG_FRAME_WARN}) endif +# force no-pie for distro compilers that enable pie by default +KBUILD_CFLAGS += $(call cc-option, -fno-pie) +KBUILD_CFLAGS += $(call cc-option, -no-pie) +KBUILD_AFLAGS += $(call cc-option, -fno-pie) + # This selects the stack protector compiler flag. Testing it is delayed # until after .config has been reprocessed, in the prepare-compiler-check # target. thanks, -- Shuah -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
