mainline inclusion
from mainline-5.11-rc1
commit 4f33a53d
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5EUVD
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4f33a53d56000cfa67e2e4e8a5dac08f084a979b

-------------------------------------------------

Teach libbpf to search for candidate types for CO-RE relocations across kernel
modules BTFs, in addition to vmlinux BTF. If at least one candidate type is
found in vmlinux BTF, kernel module BTFs are not iterated. If vmlinux BTF has
no matching candidates, then find all kernel module BTFs and search for all
matching candidates across all of them.

Kernel's support for module BTFs are inferred from the support for BTF name
pointer in BPF UAPI.
Signed-off-by: NAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201203204634.1325171-6-andrii@kernel.org
(cherry picked from commit 4f33a53d)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>