From 11bb2f7a45909f4f64afe471875672ae1b84a380 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 14 Jul 2020 12:25:34 +0200 Subject: [PATCH] bpf: Fix cross build for CONFIG_DEBUG_INFO_BTF option Stephen and 0-DAY CI Kernel Test Service reported broken cross build for arm (arm-linux-gnueabi-gcc (GCC) 9.3.0), with following output: /tmp/ccMS5uth.s: Assembler messages: /tmp/ccMS5uth.s:69: Error: unrecognized symbol type "" /tmp/ccMS5uth.s:82: Error: unrecognized symbol type "" Having '@object' for .type diretive is wrong because '@' is comment character for some architectures. Using STT_OBJECT instead that should work everywhere. Also using HOST* variables to build resolve_btfids so it's properly build in crossbuilds (stolen from objtool's Makefile). Reported-by: kernel test robot Reported-by: Stephen Rothwell Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Tested-by: Geert Uytterhoeven Link: https://lore.kernel.org/bpf/20200714102534.299280-2-jolsa@kernel.org --- include/linux/btf_ids.h | 2 +- tools/bpf/resolve_btfids/Makefile | 14 ++++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h index b3c73db9587c..1cdb56950ffe 100644 --- a/include/linux/btf_ids.h +++ b/include/linux/btf_ids.h @@ -23,7 +23,7 @@ asm( \ ".pushsection " BTF_IDS_SECTION ",\"a\"; \n" \ ".local " #symbol " ; \n" \ -".type " #symbol ", @object; \n" \ +".type " #symbol ", STT_OBJECT; \n" \ ".size " #symbol ", 4; \n" \ #symbol ": \n" \ ".zero 4 \n" \ diff --git a/tools/bpf/resolve_btfids/Makefile b/tools/bpf/resolve_btfids/Makefile index 948378ca73d4..a88cd4426398 100644 --- a/tools/bpf/resolve_btfids/Makefile +++ b/tools/bpf/resolve_btfids/Makefile @@ -16,6 +16,20 @@ else MAKEFLAGS=--no-print-directory endif +# always use the host compiler +ifneq ($(LLVM),) +HOSTAR ?= llvm-ar +HOSTCC ?= clang +HOSTLD ?= ld.lld +else +HOSTAR ?= ar +HOSTCC ?= gcc +HOSTLD ?= ld +endif +AR = $(HOSTAR) +CC = $(HOSTCC) +LD = $(HOSTLD) + OUTPUT ?= $(srctree)/tools/bpf/resolve_btfids/ LIBBPF_SRC := $(srctree)/tools/lib/bpf/