linux-stable.git/tools/lib/bpf, branch v5.5.7

libbpf: Extract and generalize CPU mask parsing logic

2020-02-11T12:37:22+00:00

commit 6803ee25f0ead1e836808acb14396bb9a9849113 upstream.

This logic is re-used for parsing a set of online CPUs. Having it as an
isolated piece of code working with input string makes it conveninent to test
this logic as well. While refactoring, also improve the robustness of original
implementation.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20191212013548.1690564-1-andriin@fb.com
Signed-off-by: Greg Kroah-Hartman

libbpf: Fix realloc usage in bpf_core_find_cands

2020-02-11T12:36:59+00:00

commit 35b9211c0a2427e8f39e534f442f43804fc8d5ca upstream.

Fix bug requesting invalid size of reallocated array when constructing CO-RE
relocation candidate list. This can cause problems if there are many potential
candidates and a very fine-grained memory allocator bucket sizes are used.

Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm")
Reported-by: William Smith 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20200124201847.212528-1-andriin@fb.com
Signed-off-by: Greg Kroah-Hartman

libbpf: Add missing newline in opts validation macro

2020-02-11T12:36:59+00:00

commit 12dd14b230b3c742b80272ecb8a83cdf824625ca upstream.

The error log output in the opts validation macro was missing a newline.

Fixes: 2ce8450ef5a3 ("libbpf: add bpf_object__open_{file, mem} w/ extensible opts")
Signed-off-by: Toke Høiland-Jørgensen 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20191219120714.928380-1-toke@redhat.com
Signed-off-by: Greg Kroah-Hartman

libbpf: Don't attach perf_buffer to offline/missing CPUs

2020-02-11T12:36:59+00:00

commit 783b8f01f5942a786998f5577bd9ff3992f22a1a upstream.

It's quite common on some systems to have more CPUs enlisted as "possible",
than there are (and could ever be) present/online CPUs. In such cases,
perf_buffer creationg will fail due to inability to create perf event on
missing CPU with error like this:

libbpf: failed to open perf buffer event on cpu #16: No such device

This patch fixes the logic of perf_buffer__new() to ignore CPUs that are
missing or currently offline. In rare cases where user explicitly listed
specific CPUs to connect to, behavior is unchanged: libbpf will try to open
perf event buffer on specified CPU(s) anyways.

Fixes: fb84b8224655 ("libbpf: add perf buffer API")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20191212013609.1691168-1-andriin@fb.com
Signed-off-by: Greg Kroah-Hartman

libbpf: Fix printf compilation warnings on ppc64le arch

2020-02-11T12:36:58+00:00

commit 679152d3a32e305c213f83160c328c37566ae8bc upstream.

On ppc64le __u64 and __s64 are defined as long int and unsigned long int,
respectively. This causes compiler to emit warning when %lld/%llu are used to
printf 64-bit numbers. Fix this by casting to size_t/ssize_t with %zu and %zd
format specifiers, respectively.

v1->v2:
- use size_t/ssize_t instead of custom typedefs (Martin).

Fixes: 1f8e2bcb2cd5 ("libbpf: Refactor relocation handling")
Fixes: abd29c931459 ("libbpf: allow specifying map definitions using BTF")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Acked-by: Martin KaFai Lau 
Link: https://lore.kernel.org/bpf/20191212171918.638010-1-andriin@fb.com
Signed-off-by: Greg Kroah-Hartman

libbpf: Fix readelf output parsing for Fedora

2020-02-11T12:36:58+00:00

commit aa915931ac3e53ccf371308e6750da510e3591dd upstream.

Fedora binutils has been patched to show "other info" for a symbol at the
end of the line. This was done in order to support unmaintained scripts
that would break with the extra info. [1]

[1] https://src.fedoraproject.org/rpms/binutils/c/b8265c46f7ddae23a792ee8306fbaaeacba83bf8

This in turn has been done to fix the build of ruby, because of checksec.
[2] Thanks Michael Ellerman for the pointer.

[2] https://bugzilla.redhat.com/show_bug.cgi?id=1479302

As libbpf Makefile is not unmaintained, we can simply deal with either
output format, by just removing the "other info" field, as it always comes
inside brackets.

Fixes: 3464afdf11f9 (libbpf: Fix readelf output parsing on powerpc with recent binutils)
Reported-by: Justin Forbes 
Signed-off-by: Thadeu Lima de Souza Cascardo 
Signed-off-by: Alexei Starovoitov 
Acked-by: Andrii Nakryiko 
Cc: Aurelien Jarno 
Link: https://lore.kernel.org/bpf/20191213101114.GA3986@calabresa
Signed-off-by: Greg Kroah-Hartman

libbpf: Fix build on read-only filesystems

2019-12-23T14:34:06+00:00

I got the following error when I tried to build perf on a read-only
filesystem with O=dir option.

  $ cd /some/where/ro/linux/tools/perf
  $ make O=$HOME/build/perf
  ...
    CC       /home/namhyung/build/perf/lib.o
  /bin/sh: bpf_helper_defs.h: Read-only file system
  make[3]: *** [Makefile:184: bpf_helper_defs.h] Error 1
  make[2]: *** [Makefile.perf:778: /home/namhyung/build/perf/libbpf.a] Error 2
  make[2]: *** Waiting for unfinished jobs....
    LD       /home/namhyung/build/perf/libperf-in.o
    AR       /home/namhyung/build/perf/libperf.a
    PERF_VERSION = 5.4.0
  make[1]: *** [Makefile.perf:225: sub-make] Error 2
  make: *** [Makefile:70: all] Error 2

It was becaused bpf_helper_defs.h was generated in current directory.
Move it to OUTPUT directory.

Signed-off-by: Namhyung Kim 
Signed-off-by: Daniel Borkmann 
Tested-by: Andrii Nakryiko 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20191223061326.843366-1-namhyung@kernel.org

selftests/bpf: Bring back c++ include/link test

2019-12-05T01:57:55+00:00

Commit 5c26f9a78358 ("libbpf: Don't use cxx to test_libpf target")
converted existing c++ test to c. We still want to include and
link against libbpf from c++ code, so reinstate this test back,
this time in a form of a selftest with a clear comment about
its purpose.

v2:
* -lelf -> $(LDLIBS) (Andrii Nakryiko)

Fixes: 5c26f9a78358 ("libbpf: Don't use cxx to test_libpf target")
Signed-off-by: Stanislav Fomichev 
Signed-off-by: Alexei Starovoitov 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20191202215931.248178-1-sdf@google.com

libbpf: Fix readelf output parsing on powerpc with recent binutils

2019-12-02T09:31:54+00:00

On powerpc with recent versions of binutils, readelf outputs an extra
field when dumping the symbols of an object file. For example:

    35: 0000000000000838    96 FUNC    LOCAL  DEFAULT [: 8]     1 btf_is_struct

The extra "[: 8]" prevents the GLOBAL_SYM_COUNT variable to
be computed correctly and causes the check_abi target to fail.

Fix that by looking for the symbol name in the last field instead of the
8th one. This way it should also cope with future extra fields.

Signed-off-by: Aurelien Jarno 
Signed-off-by: Daniel Borkmann 
Tested-by: Michael Ellerman 
Link: https://lore.kernel.org/bpf/20191201195728.4161537-1-aurelien@aurel32.net

libbpf: Fix sym->st_value print on 32-bit arches

2019-11-28T01:46:56+00:00

The st_value field is a 64-bit value and causing this error on 32-bit arches:

In file included from libbpf.c:52:
libbpf.c: In function 'bpf_program__record_reloc':
libbpf_internal.h:59:22: error: format '%lu' expects argument of type 'long unsigned int', but argument 3 has type 'Elf64_Addr' {aka 'const long long unsigned int'} [-Werror=format=]

Fix it with (__u64) cast.

Fixes: 1f8e2bcb2cd5 ("libbpf: Refactor relocation handling")
Reported-by: Arnaldo Carvalho de Melo 
Signed-off-by: Alexei Starovoitov