lkml.org 
[lkml]   [2022]   [Jul]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 5/5] tools bpftool: Fix compilation error with new binutils
Date
binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpftool/jit_disasm.c, e.g. on debian
unstable. Relevant binutils commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07

Wire up the feature test and switch to init_disassemble_info_compat(),
which were introduced in prior commits, fixing the compilation failure.

I verified that bpftool can still disassemble bpf programs, both with an
old and new dis-asm.h API. There are no output changes for plain and json
formats. When comparing the output from old binutils (2.35)
to new bintuils with the patch (upstream snapshot) there are a few output
differences, but they are unrelated to this patch. An example hunk is:
2f: pop %r14
31: pop %r13
33: pop %rbx
- 34: leaveq
- 35: retq
+ 34: leave
+ 35: ret

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Quentin Monnet <quentin@isovalent.com>
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Signed-off-by: Andres Freund <andres@anarazel.de>
---
tools/bpf/bpftool/Makefile | 7 ++++--
tools/bpf/bpftool/jit_disasm.c | 42 +++++++++++++++++++++++++++-------
2 files changed, 39 insertions(+), 10 deletions(-)

diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index c6d2c77d0252..62195118d377 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -93,9 +93,9 @@ INSTALL ?= install
RM ?= rm -f

FEATURE_USER = .bpftool
-FEATURE_TESTS = libbfd disassembler-four-args zlib libcap \
+FEATURE_TESTS = libbfd disassembler-four-args disassembler-init-styled zlib libcap \
clang-bpf-co-re
-FEATURE_DISPLAY = libbfd disassembler-four-args zlib libcap \
+FEATURE_DISPLAY = libbfd disassembler-four-args disassembler-init-styled zlib libcap \
clang-bpf-co-re

check_feat := 1
@@ -117,6 +117,9 @@ endif
ifeq ($(feature-disassembler-four-args), 1)
CFLAGS += -DDISASM_FOUR_ARGS_SIGNATURE
endif
+ifeq ($(feature-disassembler-init-styled), 1)
+ CFLAGS += -DDISASM_INIT_STYLED
+endif

LIBS = $(LIBBPF) -lelf -lz
LIBS_BOOTSTRAP = $(LIBBPF_BOOTSTRAP) -lelf -lz
diff --git a/tools/bpf/bpftool/jit_disasm.c b/tools/bpf/bpftool/jit_disasm.c
index 24734f2249d6..aaf99a0168c9 100644
--- a/tools/bpf/bpftool/jit_disasm.c
+++ b/tools/bpf/bpftool/jit_disasm.c
@@ -24,6 +24,7 @@
#include <sys/stat.h>
#include <limits.h>
#include <bpf/libbpf.h>
+#include <tools/dis-asm-compat.h>

#include "json_writer.h"
#include "main.h"
@@ -39,15 +40,12 @@ static void get_exec_path(char *tpath, size_t size)
}

static int oper_count;
-static int fprintf_json(void *out, const char *fmt, ...)
+static int printf_json(void *out, const char *fmt, va_list ap)
{
- va_list ap;
char *s;
int err;

- va_start(ap, fmt);
err = vasprintf(&s, fmt, ap);
- va_end(ap);
if (err < 0)
return -1;

@@ -73,6 +71,32 @@ static int fprintf_json(void *out, const char *fmt, ...)
return 0;
}

+static int fprintf_json(void *out, const char *fmt, ...)
+{
+ va_list ap;
+ int r;
+
+ va_start(ap, fmt);
+ r = printf_json(out, fmt, ap);
+ va_end(ap);
+
+ return r;
+}
+
+static int fprintf_json_styled(void *out,
+ enum disassembler_style style __maybe_unused,
+ const char *fmt, ...)
+{
+ va_list ap;
+ int r;
+
+ va_start(ap, fmt);
+ r = printf_json(out, fmt, ap);
+ va_end(ap);
+
+ return r;
+}
+
void disasm_print_insn(unsigned char *image, ssize_t len, int opcodes,
const char *arch, const char *disassembler_options,
const struct btf *btf,
@@ -99,11 +123,13 @@ void disasm_print_insn(unsigned char *image, ssize_t len, int opcodes,
assert(bfd_check_format(bfdf, bfd_object));

if (json_output)
- init_disassemble_info(&info, stdout,
- (fprintf_ftype) fprintf_json);
+ init_disassemble_info_compat(&info, stdout,
+ (fprintf_ftype) fprintf_json,
+ fprintf_json_styled);
else
- init_disassemble_info(&info, stdout,
- (fprintf_ftype) fprintf);
+ init_disassemble_info_compat(&info, stdout,
+ (fprintf_ftype) fprintf,
+ fprintf_styled);

/* Update architecture info for offload. */
if (arch) {
--
2.37.0.3.g30cc8d0f14
\
 
 \ /
  Last update: 2022-07-03 23:28    [W:0.520 / U:0.240 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site