[PATCH bpf-next 0/3] Fix handling of CO-RE relos for __weak subprogs

From: Andrii Nakryiko <andrii@kernel.org>
To: <bpf@vger.kernel.org>, <ast@kernel.org>, <daniel@iogearbox.net>
Cc: <andrii@kernel.org>, <kernel-team@fb.com>
Subject: [PATCH bpf-next 0/3] Fix handling of CO-RE relos for __weak subprogs
Date: Fri, 8 Apr 2022 11:14:22 -0700	[thread overview]
Message-ID: <20220408181425.2287230-1-andrii@kernel.org> (raw)

Fix the issue accidentally discovered during libbpf USDT support testing.
Libbpf overzealously complained about CO-RE relocations belonging to the code
of a __weak subprog that got overriden by another instance of that function.

Fix the issue fixed, return back to __weak __hidden annotation for USDT
BPF-side APIs.

And add CO-RE relos to linked_funcs selftest to ensure such combo keeps
working going forward.

Andrii Nakryiko (3):
  libbpf: don't error out on CO-RE relos for overriden weak subprogs
  libbpf: use weak hidden modifier for USDT BPF-side API functions
  selftests/bpf: add CO-RE relos into linked_funcs selftests

 tools/lib/bpf/libbpf.c                            | 15 +++++++++++----
 tools/lib/bpf/usdt.bpf.h                          |  6 +++---
 tools/testing/selftests/bpf/progs/linked_funcs1.c |  8 ++++++++
 tools/testing/selftests/bpf/progs/linked_funcs2.c |  8 ++++++++
 4 files changed, 30 insertions(+), 7 deletions(-)

-- 
2.30.2