Commit 155f556d authored by Rafael David Tinoco's avatar Rafael David Tinoco Committed by Alexei Starovoitov
Browse files

libbpf: Add bpf object kern_version attribute setter 



Unfortunately some distros don't have their kernel version defined
accurately in <linux/version.h> due to different long term support
reasons.

It is important to have a way to override the bpf kern_version
attribute during runtime: some old kernels might still check for
kern_version attribute during bpf_prog_load().

Signed-off-by: default avatarRafael David Tinoco <rafaeldtinoco@ubuntu.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Acked-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210323040952.2118241-1-rafaeldtinoco@ubuntu.com
parent 3ac3f314

tools/lib/bpf/libbpf.c

+10 −0
Original line number Diff line number Diff line
@@ -8270,6 +8270,16 @@ int bpf_object__btf_fd(const struct bpf_object *obj) 
	return obj->btf ? btf__fd(obj->btf) : -1;

}



int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version)

{

	if (obj->loaded)

		return -EINVAL;



	obj->kern_version = kern_version;



	return 0;

}



int bpf_object__set_priv(struct bpf_object *obj, void *priv,

			 bpf_object_clear_priv_t clear_priv)

{

tools/lib/bpf/libbpf.h

+1 −0
Original line number Diff line number Diff line
@@ -143,6 +143,7 @@ LIBBPF_API int bpf_object__unload(struct bpf_object *obj); 


LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);

LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);

LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);



struct btf;

LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);

tools/lib/bpf/libbpf.map

+1 −0
Original line number Diff line number Diff line
@@ -359,4 +359,5 @@ LIBBPF_0.4.0 { 
		bpf_linker__finalize;

		bpf_linker__free;

		bpf_linker__new;

		bpf_object__set_kversion;

} LIBBPF_0.3.0;