| Message ID | 20200929105931.461063397@linuxfoundation.org |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On Tue, Sep 29, 2020 at 6:53 AM Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote: > > From: Tony Ambardar <tony.ambardar@gmail.com> > > [ Upstream commit 746f534a4809e07f427f7d13d10f3a6a9641e5c3 ] > > 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@gmail.com> > Signed-off-by: Alexei Starovoitov <ast@kernel.org> > Acked-by: Andrii Nakryiko <andriin@fb.com> > Link: https://lore.kernel.org/bpf/20200905214831.1565465-1-Tony.Ambardar@gmail.com > Signed-off-by: Sasha Levin <sashal@kernel.org> This seems to work everywhere else, but breaks PPC64LE. Justin > --- > tools/lib/bpf/Makefile | 2 ++ > 1 file changed, 2 insertions(+) > > --- a/tools/lib/bpf/Makefile > +++ b/tools/lib/bpf/Makefile > @@ -152,6 +152,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s -- > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > sort -u | wc -l) > VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l) > > CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) > @@ -219,6 +220,7 @@ check_abi: $(OUTPUT)libbpf.so > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > sort -u > $(OUTPUT)libbpf_global_syms.tmp; \ > readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \ > sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \ > diff -u $(OUTPUT)libbpf_global_syms.tmp \ > >
[adding Michael Ellerman, linux-ppc maintainer] Hello Justin, On Tue, 29 Sep 2020 at 14:54, Justin Forbes <jmforbes@linuxtx.org> wrote: > > On Tue, Sep 29, 2020 at 6:53 AM Greg Kroah-Hartman > <gregkh@linuxfoundation.org> wrote: > > > > From: Tony Ambardar <tony.ambardar@gmail.com> > > > > [ Upstream commit 746f534a4809e07f427f7d13d10f3a6a9641e5c3 ] > > > > 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@gmail.com> > > Signed-off-by: Alexei Starovoitov <ast@kernel.org> > > Acked-by: Andrii Nakryiko <andriin@fb.com> > > Link: https://lore.kernel.org/bpf/20200905214831.1565465-1-Tony.Ambardar@gmail.com > > Signed-off-by: Sasha Levin <sashal@kernel.org> > > This seems to work everywhere else, but breaks PPC64LE. > I also ran into a PPC build error while working on some bpf problems, but it seemed like a pre-existing PPC issue. I did submit an upstream fix, which is marked for stable and being reviewed by Michael. See here for discussion and the patch: https://lkml.org/lkml/2020/9/17/668. Is that the same problem you encountered? Does that patch address your issue? Thanks, Tony > Justin > > > --- > > tools/lib/bpf/Makefile | 2 ++ > > 1 file changed, 2 insertions(+) > > > > --- a/tools/lib/bpf/Makefile > > +++ b/tools/lib/bpf/Makefile > > @@ -152,6 +152,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s -- > > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > > sort -u | wc -l) > > VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l) > > > > CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) > > @@ -219,6 +220,7 @@ check_abi: $(OUTPUT)libbpf.so > > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > > sort -u > $(OUTPUT)libbpf_global_syms.tmp; \ > > readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \ > > sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \ > > diff -u $(OUTPUT)libbpf_global_syms.tmp \ > > > >
On Wed, Sep 30, 2020 at 12:02 AM Tony Ambardar <tony.ambardar@gmail.com> wrote: > > [adding Michael Ellerman, linux-ppc maintainer] > > Hello Justin, > > On Tue, 29 Sep 2020 at 14:54, Justin Forbes <jmforbes@linuxtx.org> wrote: > > > > On Tue, Sep 29, 2020 at 6:53 AM Greg Kroah-Hartman > > <gregkh@linuxfoundation.org> wrote: > > > > > > From: Tony Ambardar <tony.ambardar@gmail.com> > > > > > > [ Upstream commit 746f534a4809e07f427f7d13d10f3a6a9641e5c3 ] > > > > > > 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@gmail.com> > > > Signed-off-by: Alexei Starovoitov <ast@kernel.org> > > > Acked-by: Andrii Nakryiko <andriin@fb.com> > > > Link: https://lore.kernel.org/bpf/20200905214831.1565465-1-Tony.Ambardar@gmail.com > > > Signed-off-by: Sasha Levin <sashal@kernel.org> > > > > This seems to work everywhere else, but breaks PPC64LE. > > > > I also ran into a PPC build error while working on some bpf problems, > but it seemed > like a pre-existing PPC issue. I did submit an upstream fix, which is > marked for stable > and being reviewed by Michael. See here for discussion and the patch: > https://lkml.org/lkml/2020/9/17/668. > > Is that the same problem you encountered? Does that patch address your issue? It is not, the issue I see is: Warning: Num of global symbols in sharedobjs/libbpf-in.o (259) does NOT match with num of versioned symbols in libbpf.so (50). Please make sure all LIBBPF_API symbols are versioned in libbpf.map. I only see it on ppc64le with this patch, all other arch that Fedora builds are fine (x86_64, i686, aarch64, armv7, s390). If I revert this patch, all builds succeed. We are using gcc 10.2.1 though. Justin > > Thanks, > Tony > > > Justin > > > > > --- > > > tools/lib/bpf/Makefile | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > --- a/tools/lib/bpf/Makefile > > > +++ b/tools/lib/bpf/Makefile > > > @@ -152,6 +152,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s -- > > > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > > > sort -u | wc -l) > > > VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > > > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ > > > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l) > > > > > > CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) > > > @@ -219,6 +220,7 @@ check_abi: $(OUTPUT)libbpf.so > > > awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > > > sort -u > $(OUTPUT)libbpf_global_syms.tmp; \ > > > readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ > > > + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ > > > grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \ > > > sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \ > > > diff -u $(OUTPUT)libbpf_global_syms.tmp \ > > > > > >
--- a/tools/lib/bpf/Makefile +++ b/tools/lib/bpf/Makefile @@ -152,6 +152,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s -- awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ sort -u | wc -l) VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}' | \ grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l) CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) @@ -219,6 +220,7 @@ check_abi: $(OUTPUT)libbpf.so awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ sort -u > $(OUTPUT)libbpf_global_syms.tmp; \ readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \ + awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'| \ grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | \ sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; \ diff -u $(OUTPUT)libbpf_global_syms.tmp \