[RFC PATCH net-next] tools/bpf: fix build with binutils >= 2.28

[Roman Gushchin <guro@fb.com>]

Bpftool build is broken with binutils version 2.28 and later.
The cause is commit 003ca0fd2286 ("Refactor disassembler selection")
in the binutils repo, which changed the disassembler() function
signature.

Fix this by checking binutils version and use an appropriate
disassembler() signature.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
---
 tools/bpf/Makefile             | 6 ++++++
 tools/bpf/bpf_jit_disasm.c     | 7 +++++++
 tools/bpf/bpftool/Makefile     | 6 ++++++
 tools/bpf/bpftool/jit_disasm.c | 5 +++++
 4 files changed, 24 insertions(+)

diff --git a/tools/bpf/Makefile b/tools/bpf/Makefile
index 07a6697466ef..3fd32fd0daa1 100644
--- a/tools/bpf/Makefile
+++ b/tools/bpf/Makefile
@@ -6,8 +6,14 @@ LEX = flex
 YACC = bison
 MAKE = make
 
+BINUTILS_VER := $(word 4, $(shell readelf -v | head -n 1))
+BINUTILS_VER_MAJ := $(word 1, $(subst ., , $(subst -, , ${BINUTILS_VER})))
+BINUTILS_VER_MIN := $(word 2, $(subst ., , $(subst -, , ${BINUTILS_VER})))
+
 CFLAGS += -Wall -O2
 CFLAGS += -D__EXPORTED_HEADERS__ -I../../include/uapi -I../../include
+CFLAGS += -DBINUTILS_VER_MAJ=${BINUTILS_VER_MAJ}
+CFLAGS += -DBINUTILS_VER_MIN=${BINUTILS_VER_MIN}
 
 %.yacc.c: %.y
 	$(YACC) -o $@ -d $<
diff --git a/tools/bpf/bpf_jit_disasm.c b/tools/bpf/bpf_jit_disasm.c
index 75bf526a0168..3ef7c8bdc0f3 100644
--- a/tools/bpf/bpf_jit_disasm.c
+++ b/tools/bpf/bpf_jit_disasm.c
@@ -72,7 +72,14 @@ static void get_asm_insns(uint8_t *image, size_t len, int opcodes)
 
 	disassemble_init_for_target(&info);
 
+#if (BINUTILS_VER_MAJ >= 2) && (BINUTILS_VER_MIN >= 28)
+	disassemble = disassembler(bfd_get_arch(bfdf),
+				   bfd_big_endian(bfdf),
+				   bfd_get_mach(bfdf),
+				   bfdf);
+#else
 	disassemble = disassembler(bfdf);
+#endif
 	assert(disassemble);
 
 	do {
diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index 3f17ad317512..94ad51bf14b5 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -40,6 +40,12 @@ CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wshadow
 CFLAGS += -D__EXPORTED_HEADERS__ -I$(srctree)/tools/include/uapi -I$(srctree)/tools/include -I$(srctree)/tools/lib/bpf -I$(srctree)/kernel/bpf/
 LIBS = -lelf -lbfd -lopcodes $(LIBBPF)
 
+BINUTILS_VER := $(word 4, $(shell readelf -v | head -n 1))
+BINUTILS_VER_MAJ := $(word 1, $(subst ., , $(subst -, , ${BINUTILS_VER})))
+BINUTILS_VER_MIN := $(word 2, $(subst ., , $(subst -, , ${BINUTILS_VER})))
+CFLAGS += -DBINUTILS_VER_MAJ=${BINUTILS_VER_MAJ}
+CFLAGS += -DBINUTILS_VER_MIN=${BINUTILS_VER_MIN}
+
 INSTALL ?= install
 RM ?= rm -f
 
diff --git a/tools/bpf/bpftool/jit_disasm.c b/tools/bpf/bpftool/jit_disasm.c
index 1551d3918d4c..eaa7127e9eeb 100644
--- a/tools/bpf/bpftool/jit_disasm.c
+++ b/tools/bpf/bpftool/jit_disasm.c
@@ -107,7 +107,12 @@ void disasm_print_insn(unsigned char *image, ssize_t len, int opcodes)
 
 	disassemble_init_for_target(&info);
 
+#if (BINUTILS_VER_MAJ >= 2) && (BINUTILS_VER_MIN >= 28)
+	disassemble = disassembler(bfd_get_arch(bfdf), bfd_big_endian(bfdf),
+				   bfd_get_mach(bfdf), bfdf);
+#else
 	disassemble = disassembler(bfdf);
+#endif
 	assert(disassemble);
 
 	if (json_output)
-- 
2.14.3