Non-ancient ip (iproute2-5.15.0, libbpf 0.7.0) refuses to load the sample with maps because we don't generate BTF:
libbpf: BTF is required, but is missing or corrupted. ERROR: opening BPF object file failed
Enable BTF by adding -g to clang flags. With that done neither of the programs load:
libbpf: prog 'func': error relocating .BTF.ext function info: -22 libbpf: prog 'func': failed to relocate calls: -22 libbpf: failed to load object 'ksft-net-drv/net/sample_ret0.bpf.o'
Andrii explains that this is because we don't specify section names for the code. Add the section names, too.
Signed-off-by: Jakub Kicinski kuba@kernel.org --- tools/testing/selftests/net/Makefile | 3 ++- tools/testing/selftests/net/bpf_offload.py | 2 +- tools/testing/selftests/net/sample_map_ret0.bpf.c | 2 +- tools/testing/selftests/net/sample_ret0.bpf.c | 3 +++ 4 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index e8bfa715aa49..a3c781cb8367 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -149,7 +149,8 @@ BPF_PROG_OBJS := $(OUTPUT)/nat6to4.o $(OUTPUT)/xdp_dummy.o \ $(OUTPUT)/sample_map_ret0.bpf.o $(OUTPUT)/sample_ret0.bpf.o
$(BPF_PROG_OBJS): $(OUTPUT)/%.o : %.c $(BPFOBJ) | $(MAKE_DIRS) - $(CLANG) -O2 --target=bpf -c $< $(CCINCLUDE) $(CLANG_SYS_INCLUDES) -o $@ + $(CLANG) -O2 -g --target=bpf $(CCINCLUDE) $(CLANG_SYS_INCLUDES) \ + -c $< -o $@
$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ $(APIDIR)/linux/bpf.h \ diff --git a/tools/testing/selftests/net/bpf_offload.py b/tools/testing/selftests/net/bpf_offload.py index 174dba1a48d3..76b53ac2c8c6 100755 --- a/tools/testing/selftests/net/bpf_offload.py +++ b/tools/testing/selftests/net/bpf_offload.py @@ -237,7 +237,7 @@ def bpftool_prog_load(sample, file_name, maps=[], prog_type="xdp", dev=None, def ethtool(dev, opt, args, fail=True): return cmd("ethtool %s %s %s" % (opt, dev["ifname"], args), fail=fail)
-def bpf_obj(name, sec=".text", path=bpf_test_dir,): +def bpf_obj(name, sec="xdp", path=bpf_test_dir,): return "obj %s sec %s" % (os.path.join(path, name), sec)
def bpf_pinned(name): diff --git a/tools/testing/selftests/net/sample_map_ret0.bpf.c b/tools/testing/selftests/net/sample_map_ret0.bpf.c index 495990d355ef..43ca92594926 100644 --- a/tools/testing/selftests/net/sample_map_ret0.bpf.c +++ b/tools/testing/selftests/net/sample_map_ret0.bpf.c @@ -17,7 +17,7 @@ struct { } array SEC(".maps");
/* Sample program which should always load for testing control paths. */ -SEC(".text") int func() +SEC("xdp") int func() { __u64 key64 = 0; __u32 key = 0; diff --git a/tools/testing/selftests/net/sample_ret0.bpf.c b/tools/testing/selftests/net/sample_ret0.bpf.c index fec99750d6ea..1df5ca98bb65 100644 --- a/tools/testing/selftests/net/sample_ret0.bpf.c +++ b/tools/testing/selftests/net/sample_ret0.bpf.c @@ -1,6 +1,9 @@ /* SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) */
+#define SEC(name) __attribute__((section(name), used)) + /* Sample program which should always load for testing control paths. */ +SEC("xdp") int func() { return 0;