commit 338d4f49d6f7114a017d294ccf7374df4f998edc ("arm64: kernel: Add support for Privileged Access Never") includes sysreg.h into futex.h and uaccess.h. But, the inline assembly used by asm/sysreg.h is incompatible with llvm so it will cause BPF samples build failure for ARM64. Since sysreg.h is useless for BPF samples, just exclude it from Makefile via defining __ASM_SYSREG_H.

Signed-off-by: Yang Shi yang.shi@linaro.org --- samples/bpf/Makefile | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 79b4596..edd638b 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -67,10 +67,13 @@ HOSTLOADLIBES_lathist += -lelf # point this to your LLVM backend with bpf support LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc

+# asm/sysreg.h inline assmbly used by it is incompatible with llvm. +# But, ehere is not easy way to fix it, so just exclude it since it is +# useless for BPF samples. $(obj)/%.o: $(src)/%.c clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \ - -D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \ + -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@ clang $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \ - -D__KERNEL__ -Wno-unused-value -Wno-pointer-sign \ + -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=asm -o $@.s