mainline inclusion
from mainline-5.13-rc1
commit 6be6a0ba
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5Q927
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6be6a0baffc1357b6d2023155753f111624c4fec

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

Also document the expansion of the kind bitfield.
Signed-off-by: NIlya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NYonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210226202256.116518-11-iii@linux.ibm.com
(cherry picked from commit 6be6a0ba)
Signed-off-by: NWang Yufen <wangyufen@huawei.com>

Conflicts:
	Documentation/bpf/btf.rst