On Tue, Sep 8, 2020 at 12:53 PM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Sat, Sep 5, 2020 at 2:49 PM Tony Ambardar <tony.ambardar@xxxxxxxxx> wrote:
> >
> > Encountered the following failure building libbpf from kernel 5.8.5 sources
> > with GCC 8.4.0 and binutils 2.34: (long paths shortened)
> >
> > Warning: Num of global symbols in sharedobjs/libbpf-in.o (234) does NOT
> > match with num of versioned symbols in libbpf.so (236). Please make sure
> > all LIBBPF_API symbols are versioned in libbpf.map.
> > --- libbpf_global_syms.tmp 2020-09-02 07:30:58.920084380 +0000
> > +++ libbpf_versioned_syms.tmp 2020-09-02 07:30:58.924084388 +0000
> > @@ -1,3 +1,5 @@
> > +_fini
> > +_init
> > bpf_btf_get_fd_by_id
> > bpf_btf_get_next_id
> > bpf_create_map
> > make[4]: *** [Makefile:210: check_abi] Error 1
> >
> > Investigation shows _fini and _init are actually local symbols counted
> > amongst global ones:
> >
> > $ readelf --dyn-syms --wide libbpf.so|head -10
> >
> > Symbol table '.dynsym' contains 343 entries:
> > Num: Value Size Type Bind Vis Ndx Name
> > 0: 00000000 0 NOTYPE LOCAL DEFAULT UND
> > 1: 00004098 0 SECTION LOCAL DEFAULT 11
> > 2: 00004098 8 FUNC LOCAL DEFAULT 11 _init@@LIBBPF_0.0.1
> > 3: 00023040 8 FUNC LOCAL DEFAULT 14 _fini@@LIBBPF_0.0.1
> > 4: 00000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.0.4
> > 5: 00000000 0 OBJECT GLOBAL DEFAULT ABS LIBBPF_0.0.1
> > 6: 0000ffa4 8 FUNC GLOBAL DEFAULT 12 bpf_object__find_map_by_offset@@LIBBPF_0.0.1
> >
> > A previous commit filtered global symbols in sharedobjs/libbpf-in.o. Do the
> > same with the libbpf.so DSO for consistent comparison.
> >
> > Fixes: 306b267cb3c4 ("libbpf: Verify versioned symbols")
> >
> > Signed-off-by: Tony Ambardar <Tony.Ambardar@xxxxxxxxx>
Applied. Thanks
