Commit Graph

43 Commits

Author SHA1 Message Date
Viktor Malik 0c7e6ff75e tools/resolve_btfids: Fix setting HOSTCFLAGS
commit edd75c8028 upstream.

Building BPF selftests with custom HOSTCFLAGS yields an error:

    # make HOSTCFLAGS="-O2"
    [...]
      HOSTCC  ./tools/testing/selftests/bpf/tools/build/resolve_btfids/main.o
    main.c:73:10: fatal error: linux/rbtree.h: No such file or directory
       73 | #include <linux/rbtree.h>
          |          ^~~~~~~~~~~~~~~~

The reason is that tools/bpf/resolve_btfids/Makefile passes header
include paths by extending HOSTCFLAGS which is overridden by setting
HOSTCFLAGS in the make command (because of Makefile rules [1]).

This patch fixes the above problem by passing the include paths via
`HOSTCFLAGS_resolve_btfids` which is used by tools/build/Build.include
and can be combined with overridding HOSTCFLAGS.

[1] https://www.gnu.org/software/make/manual/html_node/Overriding.html

Fixes: 56a2df7615 ("tools/resolve_btfids: Compile resolve_btfids as host program")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230530123352.1308488-1-vmalik@redhat.com
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Jiri Olsa 1ad863e91a tools/resolve_btfids: Pass HOSTCFLAGS as EXTRA_CFLAGS to prepare targets
commit 2531ba0e4a upstream.

Thorsten reported build issue with command line that defined extra
HOSTCFLAGS that were not passed into 'prepare' targets, but were
used to build resolve_btfids objects.

This results in build fail when these objects are linked together:

  /usr/bin/ld: /build.../tools/bpf/resolve_btfids//libbpf/libbpf.a(libbpf-in.o):
  relocation R_X86_64_32 against `.rodata.str1.1' can not be used when making a PIE \
  object; recompile with -fPIE

Fixing this by passing HOSTCFLAGS in EXTRA_CFLAGS as part of
HOST_OVERRIDES variable for prepare targets.

[1] https://lore.kernel.org/bpf/f7922132-6645-6316-5675-0ece4197bfff@leemhuis.info/

Fixes: 56a2df7615 ("tools/resolve_btfids: Compile resolve_btfids as host program")
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Thorsten Leemhuis <linux@leemhuis.info>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/bpf/20230209143735.4112845-1-jolsa@kernel.org
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Ian Rogers a2a9f5bccc tools/resolve_btfids: Tidy HOST_OVERRIDES
commit e0975ab92f upstream.

Don't set EXTRA_CFLAGS to HOSTCFLAGS, ensure CROSS_COMPILE isn't
passed through.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230202224253.40283-1-irogers@google.com
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Jiri Olsa b3f1d78c67 tools/resolve_btfids: Compile resolve_btfids as host program
commit 56a2df7615 upstream.

Making resolve_btfids to be compiled as host program so
we can avoid cross compile issues as reported by Nathan.

Also we no longer need HOST_OVERRIDES for BINARY target,
just for 'prepare' targets.

Fixes: 13e07691a1 ("tools/resolve_btfids: Alter how HOSTCC is forced")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/bpf/20230202112839.1131892-1-jolsa@kernel.org
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Ian Rogers 833a654b51 tools/resolve_btfids: Alter how HOSTCC is forced
commit 13e07691a1 upstream.

HOSTCC is always wanted when building. Setting CC to HOSTCC happens
after tools/scripts/Makefile.include is included, meaning flags are
set assuming say CC is gcc, but then it can be later set to HOSTCC
which may be clang. tools/scripts/Makefile.include is needed for host
set up and common macros in objtool's Makefile. Rather than override
CC to HOSTCC, just pass CC as HOSTCC to Makefile.build, the libsubcmd
builds and the linkage step. This means the Makefiles don't see things
like CC changing and tool flag determination, and similar, work
properly.

Also, clear the passed subdir as otherwise an outer build may break by
inadvertently passing an inappropriate value.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230124064324.672022-2-irogers@google.com
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Ian Rogers 2457021a4f tools/resolve_btfids: Install subcmd headers
commit af03299d85 upstream.

Previously tools/lib/subcmd was added to the include path, switch to
installing the headers and then including from that directory. This
avoids dependencies on headers internal to tools/lib/subcmd. Add the
missing subcmd directory to the affected #include.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20230124064324.672022-1-irogers@google.com
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Shen Jiamin d35187340a tools/resolve_btfids: Use pkg-config to locate libelf
commit 0e43662e61 upstream.

When libelf was not installed in the standard location, it cannot be
located by the current building config.

Use pkg-config to help locate libelf in such cases.

Signed-off-by: Shen Jiamin <shen_jiamin@comp.nus.edu.sg>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20221215044703.400139-1-shen_jiamin@comp.nus.edu.sg
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-09-13 09:42:27 +02:00
Kumar Kartikeya Dwivedi ef2c6f370a tools/resolve_btfids: Add support for 8-byte BTF sets
A flag is a 4-byte symbol that may follow a BTF ID in a set8. This is
used in the kernel to tag kfuncs in BTF sets with certain flags. Add
support to adjust the sorting code so that it passes size as 8 bytes
for 8-byte BTF sets.

Cc: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20220721134245.2450-3-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-21 20:59:42 -07:00
Jakub Kicinski c59400a68c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-03 17:36:16 -08:00
Nathan Chancellor 7f3bdbc3f1 tools/resolve_btfids: Do not print any commands when building silently
When building with 'make -s', there is some output from resolve_btfids:

$ make -sj"$(nproc)" oldconfig prepare
  MKDIR     .../tools/bpf/resolve_btfids/libbpf/
  MKDIR     .../tools/bpf/resolve_btfids//libsubcmd
  LINK     resolve_btfids

Silent mode means that no information should be emitted about what is
currently being done. Use the $(silent) variable from Makefile.include
to avoid defining the msg macro so that there is no information printed.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220201212503.731732-1-nathan@kernel.org
2022-02-03 16:28:49 +01:00
Connor O'Brien 0e3a1c902f tools/resolve_btfids: Build with host flags
resolve_btfids is built using $(HOSTCC) and $(HOSTLD) but does not
pick up the corresponding flags. As a result, host-specific settings
(such as a sysroot specified via HOSTCFLAGS=--sysroot=..., or a linker
specified via HOSTLDFLAGS=-fuse-ld=...) will not be respected.

Fix this by setting CFLAGS to KBUILD_HOSTCFLAGS and LDFLAGS to
KBUILD_HOSTLDFLAGS.

Also pass the cflags through to libbpf via EXTRA_CFLAGS to ensure that
the host libbpf is built with flags consistent with resolve_btfids.

Signed-off-by: Connor O'Brien <connoro@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220112002503.115968-1-connoro@google.com
2022-01-14 16:53:23 -08:00
Jean-Philippe Brucker bf1be90346 tools/resolve_btfids: Support cross-building the kernel with clang
The CROSS_COMPILE variable may be present during resolve_btfids build if
the kernel is being cross-built. Since resolve_btfids is always executed
on the host, we set CC to HOSTCC in order to use the host toolchain when
cross-building with GCC. But instead of a toolchain prefix, cross-build
with clang uses a "-target" parameter, which Makefile.include deduces
from the CROSS_COMPILE variable. In order to avoid cross-building
libbpf, clear CROSS_COMPILE before building resolve_btfids.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211216163842.829836-3-jean-philippe@linaro.org
2021-12-16 12:15:04 -08:00
Jakub Kicinski be3158290d Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Andrii Nakryiko says:

====================
bpf-next 2021-12-10 v2

We've added 115 non-merge commits during the last 26 day(s) which contain
a total of 182 files changed, 5747 insertions(+), 2564 deletions(-).

The main changes are:

1) Various samples fixes, from Alexander Lobakin.

2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov.

3) A batch of new unified APIs for libbpf, logging improvements, version
   querying, etc. Also a batch of old deprecations for old APIs and various
   bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko.

4) BPF documentation reorganization and improvements, from Christoph Hellwig
   and Dave Tucker.

5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in
   libbpf, from Hengqi Chen.

6) Verifier log fixes, from Hou Tao.

7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong.

8) Extend branch record capturing to all platforms that support it,
   from Kajol Jain.

9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi.

10) bpftool doc-generating script improvements, from Quentin Monnet.

11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet.

12) Deprecation warning fix for perf/bpf_counter, from Song Liu.

13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf,
    from Tiezhu Yang.

14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song.

15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe
    Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun,
    and others.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits)
  libbpf: Add "bool skipped" to struct bpf_map
  libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition
  bpftool: Switch bpf_object__load_xattr() to bpf_object__load()
  selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr()
  selftests/bpf: Add test for libbpf's custom log_buf behavior
  selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load()
  libbpf: Deprecate bpf_object__load_xattr()
  libbpf: Add per-program log buffer setter and getter
  libbpf: Preserve kernel error code and remove kprobe prog type guessing
  libbpf: Improve logging around BPF program loading
  libbpf: Allow passing user log setting through bpf_object_open_opts
  libbpf: Allow passing preallocated log_buf when loading BTF into kernel
  libbpf: Add OPTS-based bpf_btf_load() API
  libbpf: Fix bpf_prog_load() log_buf logic for log_level 0
  samples/bpf: Remove unneeded variable
  bpf: Remove redundant assignment to pointer t
  selftests/bpf: Fix a compilation warning
  perf/bpf_counter: Use bpf_map_create instead of bpf_create_map
  samples: bpf: Fix 'unknown warning group' build warning on Clang
  samples: bpf: Fix xdp_sample_user.o linking with Clang
  ...
====================

Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-10 15:56:13 -08:00
Kumar Kartikeya Dwivedi 3345193f6f tools/resolve_btfids: Skip unresolved symbol warning for empty BTF sets
resolve_btfids prints a warning when it finds an unresolved symbol,
(id == 0) in id_patch. This can be the case for BTF sets that are empty
(due to disabled config options), hence printing warnings for certain
builds, most recently seen in [0].

The reason behind this is because id->cnt aliases id->id in btf_id
struct, leading to empty set showing up as ID 0 when we get to id_patch,
which triggers the warning. Since sets are an exception here, accomodate
by reusing hole in btf_id for bool is_set member, setting it to true for
BTF set when setting id->cnt, and use that to skip extraneous warning.

  [0]: https://lore.kernel.org/all/1b99ae14-abb4-d18f-cc6a-d7e523b25542@gmail.com

Before:

; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko
adding symbol tcp_cubic_kfunc_ids
WARN: resolve_btfids: unresolved symbol tcp_cubic_kfunc_ids
patching addr     0: ID       0 [tcp_cubic_kfunc_ids]
sorting  addr     4: cnt      0 [tcp_cubic_kfunc_ids]
update ok for net/ipv4/tcp_cubic.ko

After:

; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko
adding symbol tcp_cubic_kfunc_ids
patching addr     0: ID       0 [tcp_cubic_kfunc_ids]
sorting  addr     4: cnt      0 [tcp_cubic_kfunc_ids]
update ok for net/ipv4/tcp_cubic.ko

Fixes: 0e32dfc80b ("bpf: Enable TCP congestion control kfunc from modules")
Reported-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211122144742.477787-4-memxor@gmail.com
2021-12-02 13:39:46 -08:00
Andrii Nakryiko 1144ab9bdf tools/resolve_btf_ids: Close ELF file on error
Fix one case where we don't do explicit clean up.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211124002325.1737739-2-andrii@kernel.org
2021-11-26 00:14:06 +01:00
Hengqi Chen 2d8f09fafc tools/resolve_btfids: Switch to new btf__type_cnt API
Replace the call to btf__get_nr_types with new API btf__type_cnt.
The old API will be deprecated in libbpf v0.7+. No functionality
change.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211022130623.1548429-4-hengqi.chen@gmail.com
2021-10-22 16:09:14 -07:00
Quentin Monnet 1478994aad tools/resolve_btfids: Install libbpf headers when building
API headers from libbpf should not be accessed directly from the
library's source directory. Instead, they should be exported with "make
install_headers". Let's make sure that resolve_btfids installs the
headers properly when building.

When descending from a parent Makefile, the specific output directories
for building the library and exporting the headers are configurable with
LIBBPF_OUT and LIBBPF_DESTDIR, respectively. This is in addition to
OUTPUT, on top of which those variables are constructed by default.

Also adjust the Makefile for the BPF selftests in order to point to the
(target) libbpf shared with other tools, instead of building a version
specific to resolve_btfids. Remove libbpf's order-only dependencies on
the include directories (they are created by libbpf and don't need to
exist beforehand).

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211007194438.34443-5-quentin@isovalent.com
2021-10-08 11:54:11 -07:00
Kumar Kartikeya Dwivedi f614f2c755 tools: Allow specifying base BTF file in resolve_btfids
This commit allows specifying the base BTF for resolving btf id
lists/sets during link time in the resolve_btfids tool. The base BTF is
set to NULL if no path is passed. This allows resolving BTF ids for
module kernel objects.

Also, drop the --no-fail option, as it is only used in case .BTF_ids
section is not present, instead make no-fail the default mode. The long
option name is same as that of pahole.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211002011757.311265-5-memxor@gmail.com
2021-10-05 17:07:41 -07:00
Andrii Nakryiko 2f38304127 libbpf: Make libbpf_version.h non-auto-generated
Turn previously auto-generated libbpf_version.h header into a normal
header file. This prevents various tricky Makefile integration issues,
simplifies the overall build process, but also allows to further extend
it with some more versioning-related APIs in the future.

To prevent accidental out-of-sync versions as defined by libbpf.map and
libbpf_version.h, Makefile checks their consistency at build time.

Simultaneously with this change bump libbpf.map to v0.6.

Also undo adding libbpf's output directory into include path for
kernel/bpf/preload, bpftool, and resolve_btfids, which is not necessary
because libbpf_version.h is just a normal header like any other.

Fixes: 0b46b75505 ("libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210913222309.3220849-1-andrii@kernel.org
2021-09-13 15:36:47 -07:00
Quentin Monnet 0b46b75505 libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations
Introduce a macro LIBBPF_DEPRECATED_SINCE(major, minor, message) to prepare
the deprecation of two API functions. This macro marks functions as deprecated
when libbpf's version reaches the values passed as an argument.

As part of this change libbpf_version.h header is added with recorded major
(LIBBPF_MAJOR_VERSION) and minor (LIBBPF_MINOR_VERSION) libbpf version macros.
They are now part of libbpf public API and can be relied upon by user code.
libbpf_version.h is installed system-wide along other libbpf public headers.

Due to this new build-time auto-generated header, in-kernel applications
relying on libbpf (resolve_btfids, bpftool, bpf_preload) are updated to
include libbpf's output directory as part of a list of include search paths.
Better fix would be to use libbpf's make_install target to install public API
headers, but that clean up is left out as a future improvement. The build
changes were tested by building kernel (with KBUILD_OUTPUT and O= specified
explicitly), bpftool, libbpf, selftests/bpf, and resolve_btfids builds. No
problems were detected.

Note that because of the constraints of the C preprocessor we have to write
a few lines of macro magic for each version used to prepare deprecation (0.6
for now).

Also, use LIBBPF_DEPRECATED_SINCE() to schedule deprecation of
btf__get_from_id() and btf__load(), which are replaced by
btf__load_from_kernel_by_id() and btf__load_into_kernel(), respectively,
starting from future libbpf v0.6. This is part of libbpf 1.0 effort ([0]).

  [0] Closes: https://github.com/libbpf/libbpf/issues/278

Co-developed-by: Quentin Monnet <quentin@isovalent.com>
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210908213226.1871016-1-andrii@kernel.org
2021-09-09 23:28:05 +02:00
Hengqi Chen 5aad036851 tools/resolve_btfids: Emit warnings and patch zero id for missing symbols
Kernel functions referenced by .BTF_ids may be changed from global to static
and get inlined or get renamed/removed, and thus disappears from BTF.
This causes kernel build failure when resolve_btfids do id patch for symbols
in .BTF_ids in vmlinux. Update resolve_btfids to emit warning messages and
patch zero id for missing symbols instead of aborting kernel build process.

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210727132532.2473636-2-hengqi.chen@gmail.com
2021-07-29 14:37:23 -07:00
Tony Ambardar 61e8aeda93 bpf: Fix libelf endian handling in resolv_btfids
The vmlinux ".BTF_ids" ELF section is declared in btf_ids.h to hold a list
of zero-filled BTF IDs, which is then patched at link-time with correct
values by resolv_btfids. The section is flagged as "allocable" to preclude
compression, but notably the section contents (BTF IDs) are untyped.

When patching the BTF IDs, resolve_btfids writes in host-native endianness
and relies on libelf for any required translation on reading and updating
vmlinux. However, since the type of the .BTF_ids section content defaults
to ELF_T_BYTE (i.e. unsigned char), no translation occurs. This results in
incorrect patched values when cross-compiling to non-native endianness,
and can manifest as kernel Oops and test failures which are difficult to
troubleshoot [1].

Explicitly set the type of patched data to ELF_T_WORD, the architecture-
neutral ELF type corresponding to the u32 BTF IDs. This enables libelf to
transparently perform any needed endian conversions.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Frank Eigler <fche@redhat.com>
Cc: Mark Wielaard <mark@klomp.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/CAPGftE_eY-Zdi3wBcgDfkz_iOr1KF10n=9mJHm1_a_PykcsoeA@mail.gmail.com [1]
Link: https://lore.kernel.org/bpf/20210618061404.818569-1-Tony.Ambardar@gmail.com
2021-06-18 17:01:00 +02:00
Stanislav Fomichev e27bfefb21 tools/resolve_btfids: Fix warnings
* make eprintf static, used only in main.c
* initialize ret in eprintf
* remove unused *tmp

v3:
* remove another err (Song Liu)

v2:
* remove unused 'int err = -1'

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20210329223143.3659983-1-sdf@google.com
2021-03-31 12:09:12 -07:00
Kun-Chuan Hsieh 41462c6e73 tools/resolve_btfids: Fix build error with older host toolchains
Older libelf.h and glibc elf.h might not yet define the ELF compression
types.

Checking and defining SHF_COMPRESSED fix the build error when compiling
with older toolchains. Also, the tool resolve_btfids is compiled with host
toolchain. The host toolchain is more likely to be older than the cross
compile toolchain.

Fixes: 51f6463aac ("tools/resolve_btfids: Fix sections with wrong alignment")
Signed-off-by: Kun-Chuan Hsieh <jetswayss@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20210224052752.5284-1-jetswayss@gmail.com
2021-02-24 17:19:11 +01:00
Stanislav Fomichev 90a82b1fa4 tools/resolve_btfids: Add /libbpf to .gitignore
This is what I see after compiling the kernel:

 # bpf-next...bpf-next/master
 ?? tools/bpf/resolve_btfids/libbpf/

Fixes: fc6b48f692 ("tools/resolve_btfids: Build libbpf and libsubcmd in separate directories")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210212010053.668700-1-sdf@google.com
2021-02-12 13:08:26 -08:00
Jiri Olsa 7962cb9b64 tools/resolve_btfids: Set srctree variable unconditionally
We want this clean to be called from tree's root Makefile,
which defines same srctree variable and that will screw
the make setup.

We actually do not use srctree being passed from outside,
so we can solve this by setting current srctree value
directly.

Also changing the way how srctree is initialized as suggested
by Andrri.

Also root Makefile does not define the implicit RM variable,
so adding RM initialization.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210205124020.683286-4-jolsa@kernel.org
2021-02-08 21:21:39 -08:00
Jiri Olsa f23130979c tools/resolve_btfids: Check objects before removing
We want this clean to be called from tree's root clean
and that one is silent if there's nothing to clean.

Adding check for all object to clean and display CLEAN
messages only if there are objects to remove.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210205124020.683286-3-jolsa@kernel.org
2021-02-08 21:21:39 -08:00
Jiri Olsa fc6b48f692 tools/resolve_btfids: Build libbpf and libsubcmd in separate directories
Setting up separate build directories for libbpf and libpsubcmd,
so it's separated from other objects and we don't get them mixed
in the future.

It also simplifies cleaning, which is now simple rm -rf.

Also there's no need for FEATURE-DUMP.libbpf and bpf_helper_defs.h
files in .gitignore anymore.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210205124020.683286-2-jolsa@kernel.org
2021-02-08 21:21:39 -08:00
Jiri Olsa 6720869280 tools/resolve_btfids: Warn when having multiple IDs for single type
The kernel image can contain multiple types (structs/unions)
with the same name. This causes distinct type hierarchies in
BTF data and makes resolve_btfids fail with error like:

  BTFIDS  vmlinux
FAILED unresolved symbol udp6_sock

as reported by Qais Yousef [1].

This change adds warning when multiple types of the same name
are detected:

  BTFIDS  vmlinux
WARN: multiple IDs found for 'file': 526, 113351 - using 526
WARN: multiple IDs found for 'sk_buff': 2744, 113958 - using 2744

We keep the lower ID for the given type instance and let the
build continue.

Also changing the 'nr' variable name to 'nr_types' to avoid confusion.

[1] https://lore.kernel.org/lkml/20201229151352.6hzmjvu3qh6p2qgg@e107158-lin/

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210105234219.970039-1-jolsa@kernel.org
2021-01-05 18:11:55 -08:00
Brendan Jackman 22e8ebe35a tools/resolve_btfids: Fix some error messages
Add missing newlines and fix polarity of strerror argument.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20201203102234.648540-1-jackmanb@google.com
2020-12-03 10:25:47 -08:00
Jean-Philippe Brucker c8a950d0d3 tools: Factor HOSTCC, HOSTLD, HOSTAR definitions
Several Makefiles in tools/ need to define the host toolchain variables.
Move their definition to tools/scripts/Makefile.include

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/bpf/20201110164310.2600671-2-jean-philippe@linaro.org
2020-11-11 12:18:22 -08:00
David S. Miller 6d772f328d Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-09-23

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

We've added 95 non-merge commits during the last 22 day(s) which contain
a total of 124 files changed, 4211 insertions(+), 2040 deletions(-).

The main changes are:

1) Full multi function support in libbpf, from Andrii.

2) Refactoring of function argument checks, from Lorenz.

3) Make bpf_tail_call compatible with functions (subprograms), from Maciej.

4) Program metadata support, from YiFei.

5) bpf iterator optimizations, from Yonghong.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-23 13:11:11 -07:00
Jiri Olsa dc3652d3f0 tools resolve_btfids: Always force HOSTARCH
Seth reported problem with cross builds, that fail
on resolve_btfids build, because we are trying to
build it on cross build arch.

Fixing this by always forcing the host arch.

Reported-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200923185735.3048198-2-jolsa@kernel.org
2020-09-23 12:43:04 -07:00
David S. Miller 3ab0a7a0c3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Two minor conflicts:

1) net/ipv4/route.c, adding a new local variable while
   moving another local variable and removing it's
   initial assignment.

2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
   One pretty prints the port mode differently, whilst another
   changes the driver to try and obtain the port mode from
   the port node rather than the switch node.

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-22 16:45:34 -07:00
David S. Miller 150f29f5e6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-09-01

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

There are two small conflicts when pulling, resolve as follows:

1) Merge conflict in tools/lib/bpf/libbpf.c between 88a8212028 ("libbpf: Factor
   out common ELF operations and improve logging") in bpf-next and 1e891e513e
   ("libbpf: Fix map index used in error message") in net-next. Resolve by taking
   the hunk in bpf-next:

        [...]
        scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx);
        data = elf_sec_data(obj, scn);
        if (!scn || !data) {
                pr_warn("elf: failed to get %s map definitions for %s\n",
                        MAPS_ELF_SEC, obj->path);
                return -EINVAL;
        }
        [...]

2) Merge conflict in drivers/net/ethernet/mellanox/mlx5/core/en/xsk/rx.c between
   9647c57b11 ("xsk: i40e: ice: ixgbe: mlx5: Test for dma_need_sync earlier for
   better performance") in bpf-next and e20f0dbf20 ("net/mlx5e: RX, Add a prefetch
   command for small L1_CACHE_BYTES") in net-next. Resolve the two locations by retaining
   net_prefetch() and taking xsk_buff_dma_sync_for_cpu() from bpf-next. Should look like:

        [...]
        xdp_set_data_meta_invalid(xdp);
        xsk_buff_dma_sync_for_cpu(xdp, rq->xsk_pool);
        net_prefetch(xdp->data);
        [...]

We've added 133 non-merge commits during the last 14 day(s) which contain
a total of 246 files changed, 13832 insertions(+), 3105 deletions(-).

The main changes are:

1) Initial support for sleepable BPF programs along with bpf_copy_from_user() helper
   for tracing to reliably access user memory, from Alexei Starovoitov.

2) Add BPF infra for writing and parsing TCP header options, from Martin KaFai Lau.

3) bpf_d_path() helper for returning full path for given 'struct path', from Jiri Olsa.

4) AF_XDP support for shared umems between devices and queues, from Magnus Karlsson.

5) Initial prep work for full BPF-to-BPF call support in libbpf, from Andrii Nakryiko.

6) Generalize bpf_sk_storage map & add local storage for inodes, from KP Singh.

7) Implement sockmap/hash updates from BPF context, from Lorenz Bauer.

8) BPF xor verification for scalar types & add BPF link iterator, from Yonghong Song.

9) Use target's prog type for BPF_PROG_TYPE_EXT prog verification, from Udip Pant.

10) Rework BPF tracing samples to use libbpf loader, from Daniel T. Lee.

11) Fix xdpsock sample to really cycle through all buffers, from Weqaar Janjua.

12) Improve type safety for tun/veth XDP frame handling, from Maciej Żenczykowski.

13) Various smaller cleanups and improvements all over the place.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-01 13:22:59 -07:00
Toke Høiland-Jørgensen 1eb832ac2d tools/bpf: build: Make sure resolve_btfids cleans up after itself
The new resolve_btfids tool did not clean up the feature detection folder
on 'make clean', and also was not called properly from the clean rule in
tools/make/ folder on its 'make clean'. This lead to stale objects being
left around, which could cause feature detection to fail on subsequent
builds.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/bpf/20200901144343.179552-1-toke@redhat.com
2020-09-01 18:04:15 +02:00
Jiri Olsa a5f53b1d59 tools resolve_btfids: Add support for set symbols
The set symbol does not have the unique number suffix,
so we need to give it a special parsing function.

This was omitted in the first batch, because there was
no set support yet, so it slipped in the testing.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-3-jolsa@kernel.org
2020-08-25 15:37:41 -07:00
Jiri Olsa 193a983c5b tools resolve_btfids: Add size check to get_id function
To make sure we don't crash on malformed symbols.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-2-jolsa@kernel.org
2020-08-25 15:37:41 -07:00
Jiri Olsa 51f6463aac tools/resolve_btfids: Fix sections with wrong alignment
The data of compressed section should be aligned to 4
(for 32bit) or 8 (for 64 bit) bytes.

The binutils ld sets sh_addralign to 1, which makes libelf
fail with misaligned section error during the update as
reported by Jesper:

   FAILED elf_update(WRITE): invalid section alignment

While waiting for ld fix, we can fix compressed sections
sh_addralign value manually.

Adding warning in -vv mode when the fix is triggered:

  $ ./tools/bpf/resolve_btfids/resolve_btfids -vv vmlinux
  ...
  section(36) .comment, size 44, link 0, flags 30, type=1
  section(37) .debug_aranges, size 45684, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 16, expected 8
  section(38) .debug_info, size 129104957, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 1, expected 8
  section(39) .debug_abbrev, size 1152583, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 1, expected 8
  section(40) .debug_line, size 7374522, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 1, expected 8
  section(41) .debug_frame, size 702463, link 0, flags 800, type=1
  section(42) .debug_str, size 1017571, link 0, flags 830, type=1
   - fixing wrong alignment sh_addralign 1, expected 8
  section(43) .debug_loc, size 3019453, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 1, expected 8
  section(44) .debug_ranges, size 1744583, link 0, flags 800, type=1
   - fixing wrong alignment sh_addralign 16, expected 8
  section(45) .symtab, size 2955888, link 46, flags 0, type=2
  section(46) .strtab, size 2613072, link 0, flags 0, type=3
  ...
  update ok for vmlinux

Another workaround is to disable compressed debug info data
CONFIG_DEBUG_INFO_COMPRESSED kernel option.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Nick Clifton <nickc@redhat.com>
Link: https://lore.kernel.org/bpf/20200819092342.259004-1-jolsa@kernel.org
2020-08-20 14:17:20 -07:00
Stanislav Fomichev d48556f456 bpf: Add missing return to resolve_btfids
int sets_patch(struct object *obj) doesn't have a 'return 0' at the end.

Fixes: fbbb68de80 ("bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200806155225.637202-1-sdf@google.com
2020-08-06 16:51:11 -07:00
Andrii Nakryiko f86ca3cffe tools/resolve_btfids: Use libbpf's btf__parse() API
Instead of re-implementing generic BTF parsing logic, use libbpf's API.
Also add .gitignore for resolve_btfids's build artifacts.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200802013219.864880-4-andriin@fb.com
2020-08-03 16:39:48 +02:00
Jiri Olsa 11bb2f7a45 bpf: Fix cross build for CONFIG_DEBUG_INFO_BTF option
Stephen and 0-DAY CI Kernel Test Service reported broken cross build
for arm (arm-linux-gnueabi-gcc (GCC) 9.3.0), with following output:

   /tmp/ccMS5uth.s: Assembler messages:
   /tmp/ccMS5uth.s:69: Error: unrecognized symbol type ""
   /tmp/ccMS5uth.s:82: Error: unrecognized symbol type ""

Having '@object' for .type  diretive is  wrong because '@' is comment
character for some architectures. Using STT_OBJECT instead that should
work everywhere.

Also using HOST* variables to build resolve_btfids so it's properly
build in crossbuilds (stolen from objtool's Makefile).

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/bpf/20200714102534.299280-2-jolsa@kernel.org
2020-07-14 10:20:31 -07:00
Jiri Olsa fbbb68de80 bpf: Add resolve_btfids tool to resolve BTF IDs in ELF object
The resolve_btfids tool scans elf object for .BTF_ids section
and resolves its symbols with BTF ID values.

It will be used to during linking time to resolve arrays of BTF
ID values used in verifier, so these IDs do not need to be
resolved in runtime.

The expected layout of .BTF_ids section is described in main.c
header. Related kernel changes are coming in following changes.

Build issue reported by 0-DAY CI Kernel Test Service.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200711215329.41165-2-jolsa@kernel.org
2020-07-13 10:42:02 -07:00