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Commit 96ed0660 authored by Andres Freund's avatar Andres Freund Committed by Arnaldo Carvalho de Melo
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tools bpf_jit_disasm: Fix compilation error with new binutils

binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpf_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 bpf_jit_disasm can still disassemble bpf programs, both
with the old and new dis-asm.h API. With old binutils there's no change in
output before/after this patch. 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:

     f4:	mov    %r14,%rsi
     f7:	mov    %r15,%rdx
     fa:	mov    $0x2a,%ecx
  -  ff:	callq  0xffffffffea8c4988
  +  ff:	call   0xffffffffea8c4988
    104:	test   %rax,%rax
    107:	jge    0x0000000000000110
    109:	xor    %eax,%eax
  - 10b:	jmpq   0x0000000000000073
  + 10b:	jmp    0x0000000000000073
    110:	cmp    $0x16,%rax

However, I had to use an older kernel to generate the bpf_jit_enabled =
2 output, as that has been broken since 5.18 / 1022a549

 ("bpf,
x86_64: Use bpf_jit_binary_pack_alloc").

  https://lore.kernel.org/20220703030210.pmjft7qc2eajzi6c@alap3.anarazel.de

Signed-off-by: default avatarAndres Freund <andres@anarazel.de>
Acked-by: default avatarQuentin Monnet <quentin@isovalent.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Ben Hutchings <benh@debian.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-6-andres@anarazel.de
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 83aa0120
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