Support BPF_PROG_TYPE_CGROUP_SYSCTL program in libbpf: identifying
program and attach types by section name, probe.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reported in [1].
With gcc 8.3.0 the following error is issued:
cc -Ibpf@sta -I. -I.. -I.././include -I.././include/uapi
-fdiagnostics-color=always -fsanitize=address,undefined -fno-omit-frame-pointer
-pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -Werror -g -fPIC -g -O2
-Werror -Wall -Wno-pointer-arith -Wno-sign-compare -MD -MQ
'bpf@sta/src_libbpf.c.o' -MF 'bpf@sta/src_libbpf.c.o.d' -o
'bpf@sta/src_libbpf.c.o' -c ../src/libbpf.c
../src/libbpf.c: In function 'bpf_object__elf_collect':
../src/libbpf.c:947:18: error: 'map_def_sz' may be used uninitialized in this
function [-Werror=maybe-uninitialized]
if (map_def_sz <= sizeof(struct bpf_map_def)) {
~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../src/libbpf.c:827:18: note: 'map_def_sz' was declared here
int i, map_idx, map_def_sz, nr_syms, nr_maps = 0, nr_maps_glob = 0;
^~~~~~~~~~
According to [2] -Wmaybe-uninitialized is enabled by -Wall.
Same error is generated by clang's -Wconditional-uninitialized.
[1] https://github.com/libbpf/libbpf/pull/29#issuecomment-481902601
[2] https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
Fixes: d859900c4c56 ("bpf, libbpf: support global data/bss/rodata sections")
Reported-by: Evgeny Vereshchagin <evvers@ya.ru>
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
vsprintf() in __base_pr() uses nonliteral format string and it breaks
compilation for those who provide corresponding extra CFLAGS, e.g.:
https://github.com/libbpf/libbpf/issues/27
If libbpf is built with the flags from PR:
libbpf.c:68:26: error: format string is not a string literal
[-Werror,-Wformat-nonliteral]
return vfprintf(stderr, format, args);
^~~~~~
1 error generated.
Ignore this warning since the use case in libbpf.c is legit.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
LIBBPF_VERSION is already used to generate libbpf.pc file but was not
actuall set.
Set it same way it's done in kernel tree. Version is in sync with
version script for DSO.
Before:
% grep Version src/libbpf.pc
Version:
After:
% grep Version src/libbpf.pc
Version: 0.0.2
Fixes: 93bc1d0 ("makefile: sync generate pkg-config file for libbpf")
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Version script was synced from kernel tree but not enabled in Makefile.
Enable it same way it's done in kernel tree.
% readelf -s --wide src/libbpf.so | grep -Eo '[^ ]+@LIBBPF_.*' | \
cut -d@ -f 3 | sort | uniq -c
121 LIBBPF_0.0.1
29 LIBBPF_0.0.2
Signed-off-by: Andrey Ignatov <rdna@fb.com>
OBJDIR was not specified for libbpf.pc. It works by default since
default value of OBJDIR is current directory, but breaks as soon as
OBJDIR is set to some other directory:
% OBJDIR=build DESTDIR=root make install
...
ar rcs build/libbpf.a build/bpf.o build/btf.o build/libbpf.o
build/libbpf_errno.o build/netlink.o build/nlattr.o build/str_error.o
build/libbpf_probes.o build/bpf_prog_linfo.o build/xsk.o
cc -shared -lelf build/bpf.o build/btf.o build/libbpf.o build/libbpf_errno.o
build/netlink.o build/nlattr.o build/str_error.o build/libbpf_probes.o
build/bpf_prog_linfo.o build/xsk.o -o build/libbpf.so
make: *** No rule to make target `libbpf.pc', needed by `all'. Stop.
Fix it.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Introduce multiple improvements to Makefile to make the build more
flexible and support install:
* Support overriding CFLAGS by user but keep required flags in place.
ALL_FLAGS is used in Makefile as recommended in [1].
* Add additional BUILD_SHARED flag to build dynamically linked flavor of
the library. If the flag is set, -fPIC is also passed to make it
possible to build .so.
* Support building in a separate directory provided by OBJDIR variable.
* Add multiple install targets. By default the library itself and libbpf
headers are installed (install target). UAPI headers can be optionally
installed by user.
* All installation paths, including PREFIX, library and include
directories can be overridden. UAPI can be made different from include
directory for libbpf headers. That makes it possible to keep latest
<linux/bpf.h> in a place that doesn't conflict with the one installed
e.g. by kernel-headers package and use it in user's build system.
* Support DESTDIR (see [2]).
* Support overriding LDFLAGS.
* Use utilities such as rm directly as recommended in [3].
* Use compiler and related programs (such as ar) via make variables as
recommended in [3].
* In clean rule remove all possible build artifacts not to rely on passed
options (e.g. if build was done w/ BUILD_SHARED, but clean w/o it).
* Document new build options in README.
[1] https://www.gnu.org/software/make/manual/html_node/Command-Variables.html#Command-Variables
[2] https://www.gnu.org/prep/standards/html_node/DESTDIR.html
[3] https://www.gnu.org/software/make/manual/html_node/Utilities-in-Makefiles.html#Utilities-in-Makefiles
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Andrey Ignatov