From: Borislav Petkov <bp@xxxxxxx> commit 256b92af784d5043eeb7d559b6d5963dcc2ecb10 upstream. Commit 20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel") disabled CET instrumentation which gets added by default by the Ubuntu gcc9 and 10 by default, but did that only for 64-bit builds. It would still fail when building a 32-bit target. So disable CET for all x86 builds. Fixes: 20bf2b378729 ("x86/build: Disable CET instrumentation in the kernel") Reported-by: AC <achirvasub@xxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Tested-by: AC <achirvasub@xxxxxxxxx> Link: https://lkml.kernel.org/r/YCCIgMHkzh/xT4ex@arch-chirva.localdomain Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/Makefile | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -61,6 +61,9 @@ endif KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow KBUILD_CFLAGS += $(call cc-option,-mno-avx,) +# Intel CET isn't enabled in the kernel +KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none) + ifeq ($(CONFIG_X86_32),y) BITS := 32 UTS_MACHINE := i386 @@ -137,9 +140,6 @@ else KBUILD_CFLAGS += -mno-red-zone KBUILD_CFLAGS += -mcmodel=kernel - # Intel CET isn't enabled in the kernel - KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none) - # -funit-at-a-time shrinks the kernel .text considerably # unfortunately it makes reading oopses harder. KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time)