linux-stable.git/tools/lib/bpf/Makefile, branch linux-5.2.y Linux kernel stable tree libbpf: add libbpf_util.h to header install. 2019-05-05T07:06:59+00:00 William Tu u9012063@gmail.com 2019-05-02T18:33:38+00:00 7080da8909844602b650c8959ecd7814d2829ea5 The libbpf_util.h is used by xsk.h, so add it to the install headers. Reported-by: Ben Pfaff <blp@ovn.org> Signed-off-by: William Tu <u9012063@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
The libbpf_util.h is used by xsk.h, so add it to
the install headers.

Reported-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: William Tu <u9012063@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2019-04-12T00:00:05+00:00 David S. Miller davem@davemloft.net 2019-04-12T00:00:05+00:00 bb23581b9b38703257acabd520aa5ebf1db008af Daniel Borkmann says: ==================== pull-request: bpf-next 2019-04-12 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Improve BPF verifier scalability for large programs through two optimizations: i) remove verifier states that are not useful in pruning, ii) stop walking parentage chain once first LIVE_READ is seen. Combined gives approx 20x speedup. Increase limits for accepting large programs under root, and add various stress tests, from Alexei. 2) Implement global data support in BPF. This enables static global variables for .data, .rodata and .bss sections to be properly handled which allows for more natural program development. This also opens up the possibility to optimize program workflow by compiling ELFs only once and later only rewriting section data before reload, from Daniel and with test cases and libbpf refactoring from Joe. 3) Add config option to generate BTF type info for vmlinux as part of the kernel build process. DWARF debug info is converted via pahole to BTF. Latter relies on libbpf and makes use of BTF deduplication algorithm which results in 100x savings compared to DWARF data. Resulting .BTF section is typically about 2MB in size, from Andrii. 4) Add BPF verifier support for stack access with variable offset from helpers and add various test cases along with it, from Andrey. 5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header so that L2 encapsulation can be used for tc tunnels, from Alan. 6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that users can define a subset of allowed __sk_buff fields that get fed into the test program, from Stanislav. 7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up various UBSAN warnings in bpftool, from Yonghong. 8) Generate a pkg-config file for libbpf, from Luca. 9) Dump program's BTF id in bpftool, from Prashant. 10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP program, from Magnus. 11) kallsyms related fixes for the case when symbols are not present in BPF selftests and samples, from Daniel ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-04-12

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Improve BPF verifier scalability for large programs through two
   optimizations: i) remove verifier states that are not useful in pruning,
   ii) stop walking parentage chain once first LIVE_READ is seen. Combined
   gives approx 20x speedup. Increase limits for accepting large programs
   under root, and add various stress tests, from Alexei.

2) Implement global data support in BPF. This enables static global variables
   for .data, .rodata and .bss sections to be properly handled which allows
   for more natural program development. This also opens up the possibility
   to optimize program workflow by compiling ELFs only once and later only
   rewriting section data before reload, from Daniel and with test cases and
   libbpf refactoring from Joe.

3) Add config option to generate BTF type info for vmlinux as part of the
   kernel build process. DWARF debug info is converted via pahole to BTF.
   Latter relies on libbpf and makes use of BTF deduplication algorithm which
   results in 100x savings compared to DWARF data. Resulting .BTF section is
   typically about 2MB in size, from Andrii.

4) Add BPF verifier support for stack access with variable offset from
   helpers and add various test cases along with it, from Andrey.

5) Extend bpf_skb_adjust_room() growth BPF helper to mark inner MAC header
   so that L2 encapsulation can be used for tc tunnels, from Alan.

6) Add support for input __sk_buff context in BPF_PROG_TEST_RUN so that
   users can define a subset of allowed __sk_buff fields that get fed into
   the test program, from Stanislav.

7) Add bpf fs multi-dimensional array tests for BTF test suite and fix up
   various UBSAN warnings in bpftool, from Yonghong.

8) Generate a pkg-config file for libbpf, from Luca.

9) Dump program's BTF id in bpftool, from Prashant.

10) libbpf fix to use smaller BPF log buffer size for AF_XDP's XDP
    program, from Magnus.

11) kallsyms related fixes for the case when symbols are not present in
    BPF selftests and samples, from Daniel
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
bpf, libbpf: support global data/bss/rodata sections 2019-04-10T00:05:47+00:00 Daniel Borkmann daniel@iogearbox.net 2019-04-09T21:20:13+00:00 d859900c4c56dc4f0f8894c92a01dad86917453e This work adds BPF loader support for global data sections to libbpf. This allows to write BPF programs in more natural C-like way by being able to define global variables and const data. Back at LPC 2018 [0] we presented a first prototype which implemented support for global data sections by extending BPF syscall where union bpf_attr would get additional memory/size pair for each section passed during prog load in order to later add this base address into the ldimm64 instruction along with the user provided offset when accessing a variable. Consensus from LPC was that for proper upstream support, it would be more desirable to use maps instead of bpf_attr extension as this would allow for introspection of these sections as well as potential live updates of their content. This work follows this path by taking the following steps from loader side: 1) In bpf_object__elf_collect() step we pick up ".data", ".rodata", and ".bss" section information. 2) If present, in bpf_object__init_internal_map() we add maps to the obj's map array that corresponds to each of the present sections. Given section size and access properties can differ, a single entry array map is created with value size that is corresponding to the ELF section size of .data, .bss or .rodata. These internal maps are integrated into the normal map handling of libbpf such that when user traverses all obj maps, they can be differentiated from user-created ones via bpf_map__is_internal(). In later steps when we actually create these maps in the kernel via bpf_object__create_maps(), then for .data and .rodata sections their content is copied into the map through bpf_map_update_elem(). For .bss this is not necessary since array map is already zero-initialized by default. Additionally, for .rodata the map is frozen as read-only after setup, such that neither from program nor syscall side writes would be possible. 3) In bpf_program__collect_reloc() step, we record the corresponding map, insn index, and relocation type for the global data. 4) And last but not least in the actual relocation step in bpf_program__relocate(), we mark the ldimm64 instruction with src_reg = BPF_PSEUDO_MAP_VALUE where in the first imm field the map's file descriptor is stored as similarly done as in BPF_PSEUDO_MAP_FD, and in the second imm field (as ldimm64 is 2-insn wide) we store the access offset into the section. Given these maps have only single element ldimm64's off remains zero in both parts. 5) On kernel side, this special marked BPF_PSEUDO_MAP_VALUE load will then store the actual target address in order to have a 'map-lookup'-free access. That is, the actual map value base address + offset. The destination register in the verifier will then be marked as PTR_TO_MAP_VALUE, containing the fixed offset as reg->off and backing BPF map as reg->map_ptr. Meaning, it's treated as any other normal map value from verification side, only with efficient, direct value access instead of actual call to map lookup helper as in the typical case. Currently, only support for static global variables has been added, and libbpf rejects non-static global variables from loading. This can be lifted until we have proper semantics for how BPF will treat multi-object BPF loads. From BTF side, libbpf will set the value type id of the types corresponding to the ".bss", ".data" and ".rodata" names which LLVM will emit without the object name prefix. The key type will be left as zero, thus making use of the key-less BTF option in array maps. Simple example dump of program using globals vars in each section: # bpftool prog [...] 6784: sched_cls name load_static_dat tag a7e1291567277844 gpl loaded_at 2019-03-11T15:39:34+0000 uid 0 xlated 1776B jited 993B memlock 4096B map_ids 2238,2237,2235,2236,2239,2240 # bpftool map show id 2237 2237: array name test_glo.bss flags 0x0 key 4B value 64B max_entries 1 memlock 4096B # bpftool map show id 2235 2235: array name test_glo.data flags 0x0 key 4B value 64B max_entries 1 memlock 4096B # bpftool map show id 2236 2236: array name test_glo.rodata flags 0x80 key 4B value 96B max_entries 1 memlock 4096B # bpftool prog dump xlated id 6784 int load_static_data(struct __sk_buff * skb): ; int load_static_data(struct __sk_buff *skb) 0: (b7) r6 = 0 ; test_reloc(number, 0, &num0); 1: (63) *(u32 *)(r10 -4) = r6 2: (bf) r2 = r10 ; int load_static_data(struct __sk_buff *skb) 3: (07) r2 += -4 ; test_reloc(number, 0, &num0); 4: (18) r1 = map[id:2238] 6: (18) r3 = map[id:2237][0]+0 <-- direct addr in .bss area 8: (b7) r4 = 0 9: (85) call array_map_update_elem#100464 10: (b7) r1 = 1 ; test_reloc(number, 1, &num1); [...] ; test_reloc(string, 2, str2); 120: (18) r8 = map[id:2237][0]+16 <-- same here at offset +16 122: (18) r1 = map[id:2239] 124: (18) r3 = map[id:2237][0]+16 126: (b7) r4 = 0 127: (85) call array_map_update_elem#100464 128: (b7) r1 = 120 ; str1[5] = 'x'; 129: (73) *(u8 *)(r9 +5) = r1 ; test_reloc(string, 3, str1); 130: (b7) r1 = 3 131: (63) *(u32 *)(r10 -4) = r1 132: (b7) r9 = 3 133: (bf) r2 = r10 ; int load_static_data(struct __sk_buff *skb) 134: (07) r2 += -4 ; test_reloc(string, 3, str1); 135: (18) r1 = map[id:2239] 137: (18) r3 = map[id:2235][0]+16 <-- direct addr in .data area 139: (b7) r4 = 0 140: (85) call array_map_update_elem#100464 141: (b7) r1 = 111 ; __builtin_memcpy(&str2[2], "hello", sizeof("hello")); 142: (73) *(u8 *)(r8 +6) = r1 <-- further access based on .bss data 143: (b7) r1 = 108 144: (73) *(u8 *)(r8 +5) = r1 [...] For Cilium use-case in particular, this enables migrating configuration constants from Cilium daemon's generated header defines into global data sections such that expensive runtime recompilations with LLVM can be avoided altogether. Instead, the ELF file becomes effectively a "template", meaning, it is compiled only once (!) and the Cilium daemon will then rewrite relevant configuration data from the ELF's .data or .rodata sections directly instead of recompiling the program. The updated ELF is then loaded into the kernel and atomically replaces the existing program in the networking datapath. More info in [0]. Based upon recent fix in LLVM, commit c0db6b6bd444 ("[BPF] Don't fail for static variables"). [0] LPC 2018, BPF track, "ELF relocation for static data in BPF", http://vger.kernel.org/lpc-bpf2018.html#session-3 Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
This work adds BPF loader support for global data sections
to libbpf. This allows to write BPF programs in more natural
C-like way by being able to define global variables and const
data.

Back at LPC 2018 [0] we presented a first prototype which
implemented support for global data sections by extending BPF
syscall where union bpf_attr would get additional memory/size
pair for each section passed during prog load in order to later
add this base address into the ldimm64 instruction along with
the user provided offset when accessing a variable. Consensus
from LPC was that for proper upstream support, it would be
more desirable to use maps instead of bpf_attr extension as
this would allow for introspection of these sections as well
as potential live updates of their content. This work follows
this path by taking the following steps from loader side:

 1) In bpf_object__elf_collect() step we pick up ".data",
    ".rodata", and ".bss" section information.

 2) If present, in bpf_object__init_internal_map() we add
    maps to the obj's map array that corresponds to each
    of the present sections. Given section size and access
    properties can differ, a single entry array map is
    created with value size that is corresponding to the
    ELF section size of .data, .bss or .rodata. These
    internal maps are integrated into the normal map
    handling of libbpf such that when user traverses all
    obj maps, they can be differentiated from user-created
    ones via bpf_map__is_internal(). In later steps when
    we actually create these maps in the kernel via
    bpf_object__create_maps(), then for .data and .rodata
    sections their content is copied into the map through
    bpf_map_update_elem(). For .bss this is not necessary
    since array map is already zero-initialized by default.
    Additionally, for .rodata the map is frozen as read-only
    after setup, such that neither from program nor syscall
    side writes would be possible.

 3) In bpf_program__collect_reloc() step, we record the
    corresponding map, insn index, and relocation type for
    the global data.

 4) And last but not least in the actual relocation step in
    bpf_program__relocate(), we mark the ldimm64 instruction
    with src_reg = BPF_PSEUDO_MAP_VALUE where in the first
    imm field the map's file descriptor is stored as similarly
    done as in BPF_PSEUDO_MAP_FD, and in the second imm field
    (as ldimm64 is 2-insn wide) we store the access offset
    into the section. Given these maps have only single element
    ldimm64's off remains zero in both parts.

 5) On kernel side, this special marked BPF_PSEUDO_MAP_VALUE
    load will then store the actual target address in order
    to have a 'map-lookup'-free access. That is, the actual
    map value base address + offset. The destination register
    in the verifier will then be marked as PTR_TO_MAP_VALUE,
    containing the fixed offset as reg->off and backing BPF
    map as reg->map_ptr. Meaning, it's treated as any other
    normal map value from verification side, only with
    efficient, direct value access instead of actual call to
    map lookup helper as in the typical case.

Currently, only support for static global variables has been
added, and libbpf rejects non-static global variables from
loading. This can be lifted until we have proper semantics
for how BPF will treat multi-object BPF loads. From BTF side,
libbpf will set the value type id of the types corresponding
to the ".bss", ".data" and ".rodata" names which LLVM will
emit without the object name prefix. The key type will be
left as zero, thus making use of the key-less BTF option in
array maps.

Simple example dump of program using globals vars in each
section:

  # bpftool prog
  [...]
  6784: sched_cls  name load_static_dat  tag a7e1291567277844  gpl
        loaded_at 2019-03-11T15:39:34+0000  uid 0
        xlated 1776B  jited 993B  memlock 4096B  map_ids 2238,2237,2235,2236,2239,2240

  # bpftool map show id 2237
  2237: array  name test_glo.bss  flags 0x0
        key 4B  value 64B  max_entries 1  memlock 4096B
  # bpftool map show id 2235
  2235: array  name test_glo.data  flags 0x0
        key 4B  value 64B  max_entries 1  memlock 4096B
  # bpftool map show id 2236
  2236: array  name test_glo.rodata  flags 0x80
        key 4B  value 96B  max_entries 1  memlock 4096B

  # bpftool prog dump xlated id 6784
  int load_static_data(struct __sk_buff * skb):
  ; int load_static_data(struct __sk_buff *skb)
     0: (b7) r6 = 0
  ; test_reloc(number, 0, &num0);
     1: (63) *(u32 *)(r10 -4) = r6
     2: (bf) r2 = r10
  ; int load_static_data(struct __sk_buff *skb)
     3: (07) r2 += -4
  ; test_reloc(number, 0, &num0);
     4: (18) r1 = map[id:2238]
     6: (18) r3 = map[id:2237][0]+0    <-- direct addr in .bss area
     8: (b7) r4 = 0
     9: (85) call array_map_update_elem#100464
    10: (b7) r1 = 1
  ; test_reloc(number, 1, &num1);
  [...]
  ; test_reloc(string, 2, str2);
   120: (18) r8 = map[id:2237][0]+16   <-- same here at offset +16
   122: (18) r1 = map[id:2239]
   124: (18) r3 = map[id:2237][0]+16
   126: (b7) r4 = 0
   127: (85) call array_map_update_elem#100464
   128: (b7) r1 = 120
  ; str1[5] = 'x';
   129: (73) *(u8 *)(r9 +5) = r1
  ; test_reloc(string, 3, str1);
   130: (b7) r1 = 3
   131: (63) *(u32 *)(r10 -4) = r1
   132: (b7) r9 = 3
   133: (bf) r2 = r10
  ; int load_static_data(struct __sk_buff *skb)
   134: (07) r2 += -4
  ; test_reloc(string, 3, str1);
   135: (18) r1 = map[id:2239]
   137: (18) r3 = map[id:2235][0]+16   <-- direct addr in .data area
   139: (b7) r4 = 0
   140: (85) call array_map_update_elem#100464
   141: (b7) r1 = 111
  ; __builtin_memcpy(&str2[2], "hello", sizeof("hello"));
   142: (73) *(u8 *)(r8 +6) = r1       <-- further access based on .bss data
   143: (b7) r1 = 108
   144: (73) *(u8 *)(r8 +5) = r1
  [...]

For Cilium use-case in particular, this enables migrating configuration
constants from Cilium daemon's generated header defines into global
data sections such that expensive runtime recompilations with LLVM can
be avoided altogether. Instead, the ELF file becomes effectively a
"template", meaning, it is compiled only once (!) and the Cilium daemon
will then rewrite relevant configuration data from the ELF's .data or
.rodata sections directly instead of recompiling the program. The
updated ELF is then loaded into the kernel and atomically replaces
the existing program in the networking datapath. More info in [0].

Based upon recent fix in LLVM, commit c0db6b6bd444 ("[BPF] Don't fail
for static variables").

  [0] LPC 2018, BPF track, "ELF relocation for static data in BPF",
      http://vger.kernel.org/lpc-bpf2018.html#session-3

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
tools/bpf: generate pkg-config file for libbpf 2019-03-28T16:06:03+00:00 Luca Boccassi bluca@debian.org 2019-03-28T11:33:53+00:00 dd399ac9e343c7573c47d6820e4a23013c54749d Generate a libbpf.pc file at build time so that users can rely on pkg-config to find the library, its CFLAGS and LDFLAGS. Signed-off-by: Luca Boccassi <bluca@debian.org> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 
Generate a libbpf.pc file at build time so that users can rely
on pkg-config to find the library, its CFLAGS and LDFLAGS.

Signed-off-by: Luca Boccassi <bluca@debian.org>
Acked-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpf, libbpf: fix quiet install_headers 2019-03-28T16:01:37+00:00 Daniel Borkmann daniel@iogearbox.net 2019-03-28T15:44:28+00:00 8543e437807970166c2b66b79935c9f4b0e6d1f9 Both btf.h and xsk.h headers are not installed quietly due to missing '\' for the call to QUIET_INSTALL. Lets fix it. Before: # make install_headers INSTALL headers if [ ! -d '''/usr/local/include/bpf' ]; then install -d -m 755 '''/usr/local/include/bpf'; fi; install btf.h -m 644 '''/usr/local/include/bpf'; if [ ! -d '''/usr/local/include/bpf' ]; then install -d -m 755 '''/usr/local/include/bpf'; fi; install xsk.h -m 644 '''/usr/local/include/bpf'; # ls /usr/local/include/bpf/ bpf.h btf.h libbpf.h xsk.h After: # make install_headers INSTALL headers # ls /usr/local/include/bpf/ bpf.h btf.h libbpf.h xsk.h Fixes: a493f5f9d8c2 ("libbpf: Install btf.h with libbpf") Fixes: 379e2014c95b ("libbpf: add xsk.h to install_headers target") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> 
Both btf.h and xsk.h headers are not installed quietly due to
missing '\' for the call to QUIET_INSTALL. Lets fix it.

Before:

  # make install_headers
    INSTALL  headers
  if [ ! -d '''/usr/local/include/bpf' ]; then install -d -m 755 '''/usr/local/include/bpf'; fi; install btf.h -m 644 '''/usr/local/include/bpf';
  if [ ! -d '''/usr/local/include/bpf' ]; then install -d -m 755 '''/usr/local/include/bpf'; fi; install xsk.h -m 644 '''/usr/local/include/bpf';
  # ls /usr/local/include/bpf/
  bpf.h  btf.h  libbpf.h  xsk.h

After:

  # make install_headers
    INSTALL  headers
  # ls /usr/local/include/bpf/
  bpf.h  btf.h  libbpf.h  xsk.h

Fixes: a493f5f9d8c2 ("libbpf: Install btf.h with libbpf")
Fixes: 379e2014c95b ("libbpf: add xsk.h to install_headers target")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
libbpf: add libelf dependency to shared library build 2019-03-28T15:24:52+00:00 Björn Töpel bjorn.topel@intel.com 2019-03-27T13:51:14+00:00 89dedaef49d36adc2bb5e7e4c38b52fa3013c7c8 The DPDK project is moving forward with its AF_XDP PMD, and during that process some libbpf issues surfaced [1]: When libbpf was built as a shared library, libelf was not included in the linking phase. Since libelf is an internal depedency to libbpf, libelf should be included. This patch adds '-lelf' to resolve that. [1] https://patches.dpdk.org/patch/50704/#93571 Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check") Suggested-by: Luca Boccassi <bluca@debian.org> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 
The DPDK project is moving forward with its AF_XDP PMD, and during
that process some libbpf issues surfaced [1]: When libbpf was built
as a shared library, libelf was not included in the linking phase.
Since libelf is an internal depedency to libbpf, libelf should be
included. This patch adds '-lelf' to resolve that.

  [1] https://patches.dpdk.org/patch/50704/#93571

Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check")
Suggested-by: Luca Boccassi <bluca@debian.org>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
libbpf: add xsk.h to install_headers target 2019-03-28T15:24:21+00:00 Björn Töpel bjorn.topel@intel.com 2019-03-27T13:51:13+00:00 379e2014c95b7a454713da822b8ef4ec51ab8a75 The xsk.h header file was missing from the install_headers target in the Makefile. This patch simply adds xsk.h to the set of installed headers. Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets") Reported-by: Bruce Richardson <bruce.richardson@intel.com> Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 
The xsk.h header file was missing from the install_headers target in
the Makefile. This patch simply adds xsk.h to the set of installed
headers.

Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets")
Reported-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
bpf, libbpf: fix version info and add it to shared object 2019-03-25T02:49:04+00:00 Daniel Borkmann daniel@iogearbox.net 2019-03-23T00:49:10+00:00 1d382264d911d91a8be5dbed1f0e053eb3245d81 Even though libbpf's versioning script for the linker (libbpf.map) is pointing to 0.0.2, the BPF_EXTRAVERSION in the Makefile has not been updated along with it and is therefore still on 0.0.1. While fixing up, I also noticed that the generated shared object versioning information is missing, typical convention is to have a linker name (libbpf.so), soname (libbpf.so.0) and real name (libbpf.so.0.0.2) for library management. This is based upon the LIBBPF_VERSION as well. The build will then produce the following bpf libraries: # ll libbpf* libbpf.a libbpf.so -> libbpf.so.0.0.2 libbpf.so.0 -> libbpf.so.0.0.2 libbpf.so.0.0.2 # readelf -d libbpf.so.0.0.2 | grep SONAME 0x000000000000000e (SONAME) Library soname: [libbpf.so.0] And install them accordingly: # rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld install Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/nlattr.o CC /tmp/bld/btf.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so.0.0.2 LINK /tmp/bld/test_libbpf INSTALL /tmp/bld/libbpf.a INSTALL /tmp/bld/libbpf.so.0.0.2 # ll /usr/local/lib64/libbpf.* /usr/local/lib64/libbpf.a /usr/local/lib64/libbpf.so -> libbpf.so.0.0.2 /usr/local/lib64/libbpf.so.0 -> libbpf.so.0.0.2 /usr/local/lib64/libbpf.so.0.0.2 Fixes: 1bf4b05810fe ("tools: bpftool: add probes for eBPF program types") Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check") Reported-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Even though libbpf's versioning script for the linker (libbpf.map)
is pointing to 0.0.2, the BPF_EXTRAVERSION in the Makefile has
not been updated along with it and is therefore still on 0.0.1.

While fixing up, I also noticed that the generated shared object
versioning information is missing, typical convention is to have
a linker name (libbpf.so), soname (libbpf.so.0) and real name
(libbpf.so.0.0.2) for library management. This is based upon the
LIBBPF_VERSION as well.

The build will then produce the following bpf libraries:

  # ll libbpf*
  libbpf.a
  libbpf.so -> libbpf.so.0.0.2
  libbpf.so.0 -> libbpf.so.0.0.2
  libbpf.so.0.0.2

  # readelf -d libbpf.so.0.0.2 | grep SONAME
  0x000000000000000e (SONAME)             Library soname: [libbpf.so.0]

And install them accordingly:

  # rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld install

  Auto-detecting system features:
  ...                        libelf: [ on  ]
  ...                           bpf: [ on  ]

    CC       /tmp/bld/libbpf.o
    CC       /tmp/bld/bpf.o
    CC       /tmp/bld/nlattr.o
    CC       /tmp/bld/btf.o
    CC       /tmp/bld/libbpf_errno.o
    CC       /tmp/bld/str_error.o
    CC       /tmp/bld/netlink.o
    CC       /tmp/bld/bpf_prog_linfo.o
    CC       /tmp/bld/libbpf_probes.o
    CC       /tmp/bld/xsk.o
    LD       /tmp/bld/libbpf-in.o
    LINK     /tmp/bld/libbpf.a
    LINK     /tmp/bld/libbpf.so.0.0.2
    LINK     /tmp/bld/test_libbpf
    INSTALL  /tmp/bld/libbpf.a
    INSTALL  /tmp/bld/libbpf.so.0.0.2

  # ll /usr/local/lib64/libbpf.*
  /usr/local/lib64/libbpf.a
  /usr/local/lib64/libbpf.so -> libbpf.so.0.0.2
  /usr/local/lib64/libbpf.so.0 -> libbpf.so.0.0.2
  /usr/local/lib64/libbpf.so.0.0.2

Fixes: 1bf4b05810fe ("tools: bpftool: add probes for eBPF program types")
Fixes: 1b76c13e4b36 ("bpf tools: Introduce 'bpf' library and add bpf feature check")
Reported-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
libbpf: force fixdep compilation at the start of the build 2019-03-07T09:44:41+00:00 Stanislav Fomichev sdf@google.com 2019-03-06T19:59:27+00:00 8e2688876c7f7073d925e1f150e86b8ed3338f52 libbpf targets don't explicitly depend on fixdep target, so when we do 'make -j$(nproc)', there is a high probability, that some objects will be built before fixdep binary is available. Fix this by running sub-make; this makes sure that fixdep dependency is properly accounted for. For the same issue in perf, see commit abb26210a395 ("perf tools: Force fixdep compilation at the start of the build"). Before: $ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/ Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] HOSTCC /tmp/bld/fixdep.o CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/btf.o CC /tmp/bld/nlattr.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o HOSTLD /tmp/bld/fixdep-in.o LINK /tmp/bld/fixdep LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so LINK /tmp/bld/test_libbpf $ head /tmp/bld/.libbpf.o.cmd # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep) # using basic dep data /tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \ /usr/include/stdlib.h /usr/include/features.h \ /usr/include/x86_64-linux-gnu/sys/cdefs.h \ /usr/include/x86_64-linux-gnu/bits/wordsize.h \ /usr/include/x86_64-linux-gnu/gnu/stubs.h \ /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \ /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \ After: $ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/ Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] HOSTCC /tmp/bld/fixdep.o HOSTLD /tmp/bld/fixdep-in.o LINK /tmp/bld/fixdep CC /tmp/bld/libbpf.o CC /tmp/bld/bpf.o CC /tmp/bld/nlattr.o CC /tmp/bld/btf.o CC /tmp/bld/libbpf_errno.o CC /tmp/bld/str_error.o CC /tmp/bld/netlink.o CC /tmp/bld/bpf_prog_linfo.o CC /tmp/bld/libbpf_probes.o CC /tmp/bld/xsk.o LD /tmp/bld/libbpf-in.o LINK /tmp/bld/libbpf.a LINK /tmp/bld/libbpf.so LINK /tmp/bld/test_libbpf $ head /tmp/bld/.libbpf.o.cmd cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c source_/tmp/bld/libbpf.o := libbpf.c deps_/tmp/bld/libbpf.o := \ /usr/include/stdc-predef.h \ /usr/include/stdlib.h \ /usr/include/features.h \ /usr/include/x86_64-linux-gnu/sys/cdefs.h \ /usr/include/x86_64-linux-gnu/bits/wordsize.h \ Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 
libbpf targets don't explicitly depend on fixdep target, so when
we do 'make -j$(nproc)', there is a high probability, that some
objects will be built before fixdep binary is available.

Fix this by running sub-make; this makes sure that fixdep dependency
is properly accounted for.

For the same issue in perf, see commit abb26210a395 ("perf tools: Force
fixdep compilation at the start of the build").

Before:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
 # cannot find fixdep (/usr/local/google/home/sdf/src/linux/xxx//fixdep)
 # using basic dep data

/tmp/bld/libbpf.o: libbpf.c /usr/include/stdc-predef.h \
 /usr/include/stdlib.h /usr/include/features.h \
 /usr/include/x86_64-linux-gnu/sys/cdefs.h \
 /usr/include/x86_64-linux-gnu/bits/wordsize.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs.h \
 /usr/include/x86_64-linux-gnu/gnu/stubs-64.h \
 /usr/lib/gcc/x86_64-linux-gnu/7/include/stddef.h \

After:

$ rm -rf /tmp/bld; mkdir /tmp/bld; make -j$(nproc) O=/tmp/bld -C tools/lib/bpf/

Auto-detecting system features:
...                        libelf: [ on  ]
...                           bpf: [ on  ]

  HOSTCC   /tmp/bld/fixdep.o
  HOSTLD   /tmp/bld/fixdep-in.o
  LINK     /tmp/bld/fixdep
  CC       /tmp/bld/libbpf.o
  CC       /tmp/bld/bpf.o
  CC       /tmp/bld/nlattr.o
  CC       /tmp/bld/btf.o
  CC       /tmp/bld/libbpf_errno.o
  CC       /tmp/bld/str_error.o
  CC       /tmp/bld/netlink.o
  CC       /tmp/bld/bpf_prog_linfo.o
  CC       /tmp/bld/libbpf_probes.o
  CC       /tmp/bld/xsk.o
  LD       /tmp/bld/libbpf-in.o
  LINK     /tmp/bld/libbpf.a
  LINK     /tmp/bld/libbpf.so
  LINK     /tmp/bld/test_libbpf

$ head /tmp/bld/.libbpf.o.cmd
cmd_/tmp/bld/libbpf.o := gcc -Wp,-MD,/tmp/bld/.libbpf.o.d -Wp,-MT,/tmp/bld/libbpf.o -g -Wall -DHAVE_LIBELF_MMAP_SUPPORT -DCOMPAT_NEED_REALLOCARRAY -Wbad-function-cast -Wdeclaration-after-statement -Wformat-security -Wformat-y2k -Winit-self -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wno-system-headers -Wold-style-definition -Wpacked -Wredundant-decls -Wshadow -Wstrict-prototypes -Wswitch-default -Wswitch-enum -Wundef -Wwrite-strings -Wformat -Wstrict-aliasing=3 -Werror -Wall -fPIC -I. -I/usr/local/google/home/sdf/src/linux/tools/include -I/usr/local/google/home/sdf/src/linux/tools/arch/x86/include/uapi -I/usr/local/google/home/sdf/src/linux/tools/include/uapi -fvisibility=hidden -D"BUILD_STR(s)=$(pound)s" -c -o /tmp/bld/libbpf.o libbpf.c

source_/tmp/bld/libbpf.o := libbpf.c

deps_/tmp/bld/libbpf.o := \
  /usr/include/stdc-predef.h \
  /usr/include/stdlib.h \
  /usr/include/features.h \
  /usr/include/x86_64-linux-gnu/sys/cdefs.h \
  /usr/include/x86_64-linux-gnu/bits/wordsize.h \

Fixes: 7c422f557266 ("tools build: Build fixdep helper from perf and basic libs")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
tools: libbpf: make sure readelf shows full names in build checks 2019-02-28T23:53:46+00:00 Jakub Kicinski jakub.kicinski@netronome.com 2019-02-28T03:04:14+00:00 771744f9dc9742dc4259eb57f3a687d1630e1159 readelf truncates its output by default to attempt to make it more readable. This can lead to function names getting aliased if they differ late in the string. Use --wide parameter to avoid truncation. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 
readelf truncates its output by default to attempt to make it more
readable.  This can lead to function names getting aliased if they
differ late in the string.  Use --wide parameter to avoid
truncation.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>