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[v2,bpf-next,0/2] Strip away modifiers from BPF skeleton global variables

Message ID 20200713232409.3062144-1-andriin@fb.com
Headers show
Series Strip away modifiers from BPF skeleton global variables | expand

Message

Andrii Nakryiko July 13, 2020, 11:24 p.m. UTC 
Fix bpftool logic of stripping away const/volatile modifiers for all global
variables during BPF skeleton generation. See patch #1 for details on when
existing logic breaks and why it's important. Support special .strip_mods=true
mode in btf_dump__emit_type_decl.

Recent example of when this has caused problems can be found in [0].

  [0] https://github.com/iovisor/bcc/pull/2994#issuecomment-650588533

Cc: Anton Protopopov <a.s.protopopov@gmail.com>

Andrii Nakryiko (2):
  libbpf: support stripping modifiers for btf_dump
  tools/bpftool: strip away modifiers from global variables

 tools/bpf/bpftool/gen.c                       | 23 ++++++++-----------
 tools/lib/bpf/btf.h                           |  4 +++-
 tools/lib/bpf/btf_dump.c                      | 10 ++++++--
 .../selftests/bpf/prog_tests/skeleton.c       |  6 ++---
 .../selftests/bpf/progs/test_skeleton.c       |  6 +++--
 5 files changed, 28 insertions(+), 21 deletions(-)

Comments

Alexei Starovoitov July 14, 2020, 12:11 a.m. UTC | #1 
On Mon, Jul 13, 2020 at 4:25 PM Andrii Nakryiko <andriin@fb.com> wrote:
>
> Fix bpftool logic of stripping away const/volatile modifiers for all global
> variables during BPF skeleton generation. See patch #1 for details on when
> existing logic breaks and why it's important. Support special .strip_mods=true
> mode in btf_dump__emit_type_decl.
>
> Recent example of when this has caused problems can be found in [0].
>
>   [0] https://github.com/iovisor/bcc/pull/2994#issuecomment-650588533

Applied. Thanks