Commit graph

690 commits

Author SHA1 Message Date
Yinjun Zhang edc21dc909 bpftool: Fix the error when lookup in no-btf maps
When reworking btf__get_from_id() in commit a19f93cfaf the error
handling when calling bpf_btf_get_fd_by_id() changed. Before the rework
if bpf_btf_get_fd_by_id() failed the error would not be propagated to
callers of btf__get_from_id(), after the rework it is. This lead to a
change in behavior in print_key_value() that now prints an error when
trying to lookup keys in maps with no btf available.

Fix this by following the way used in dumping maps to allow to look up
keys in no-btf maps, by which it decides whether and where to get the
btf info according to the btf value type.

Fixes: a19f93cfaf ("libbpf: Add internal helper to load BTF data by FD")
Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Niklas Söderlund <niklas.soderlund@corigine.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/1644249625-22479-1-git-send-email-yinjun.zhang@corigine.com
2022-02-15 09:03:40 -08:00
Quentin Monnet 9910a74d6e bpftool: Update versioning scheme, align on libbpf's version number
Since the notion of versions was introduced for bpftool, it has been
following the version number of the kernel (using the version number
corresponding to the tree in which bpftool's sources are located). The
rationale was that bpftool's features are loosely tied to BPF features
in the kernel, and that we could defer versioning to the kernel
repository itself.

But this versioning scheme is confusing today, because a bpftool binary
should be able to work with both older and newer kernels, even if some
of its recent features won't be available on older systems. Furthermore,
if bpftool is ported to other systems in the future, keeping a
Linux-based version number is not a good option.

Looking at other options, we could either have a totally independent
scheme for bpftool, or we could align it on libbpf's version number
(with an offset on the major version number, to avoid going backwards).
The latter comes with a few drawbacks:

- We may want bpftool releases in-between two libbpf versions. We can
  always append pre-release numbers to distinguish versions, although
  those won't look as "official" as something with a proper release
  number. But at the same time, having bpftool with version numbers that
  look "official" hasn't really been an issue so far.

- If no new feature lands in bpftool for some time, we may move from
  e.g. 6.7.0 to 6.8.0 when libbpf levels up and have two different
  versions which are in fact the same.

- Following libbpf's versioning scheme sounds better than kernel's, but
  ultimately it doesn't make too much sense either, because even though
  bpftool uses the lib a lot, its behaviour is not that much conditioned
  by the internal evolution of the library (or by new APIs that it may
  not use).

Having an independent versioning scheme solves the above, but at the
cost of heavier maintenance. Developers will likely forget to increase
the numbers when adding features or bug fixes, and we would take the
risk of having to send occasional "catch-up" patches just to update the
version number.

Based on these considerations, this patch aligns bpftool's version
number on libbpf's. This is not a perfect solution, but 1) it's
certainly an improvement over the current scheme, 2) the issues raised
above are all minor at the moment, and 3) we can still move to an
independent scheme in the future if we realise we need it.

Given that libbpf is currently at version 0.7.0, and bpftool, before
this patch, was at 5.16, we use an offset of 6 for the major version,
bumping bpftool to 6.7.0. Libbpf does not export its patch number;
leave bpftool's patch number at 0 for now.

It remains possible to manually override the version number by setting
BPFTOOL_VERSION when calling make.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220210104237.11649-3-quentin@isovalent.com
2022-02-10 21:09:47 -08:00
Quentin Monnet 61fce9693f bpftool: Add libbpf's version number to "bpftool version" output
To help users check what version of libbpf is being used with bpftool,
print the number along with bpftool's own version number.

Output:

    $ ./bpftool version
    ./bpftool v5.16.0
    using libbpf v0.7
    features: libbfd, libbpf_strict, skeletons

    $ ./bpftool version --json --pretty
    {
        "version": "5.16.0",
        "libbpf_version": "0.7",
        "features": {
            "libbfd": true,
            "libbpf_strict": true,
            "skeletons": true
        }
    }

Note that libbpf does not expose its patch number.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220210104237.11649-2-quentin@isovalent.com
2022-02-10 21:09:47 -08:00
Alexei Starovoitov 28d743f671 bpftool: Generalize light skeleton generation.
Generealize light skeleton by hiding mmap details in skel_internal.h
In this form generated lskel.h is usable both by user space and by the kernel.

Note that previously #include <bpf/bpf.h> was in *.lskel.h file.
To avoid #ifdef-s in a generated lskel.h the include of bpf.h is moved
to skel_internal.h, but skel_internal.h is also used by gen_loader.c
which is part of libbpf. Therefore skel_internal.h does #include "bpf.h"
in case of user space, so gen_loader.c and lskel.h have necessary definitions.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220209232001.27490-4-alexei.starovoitov@gmail.com
2022-02-10 23:31:51 +01:00
Jakub Kicinski 1127170d45 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-02-09

We've added 126 non-merge commits during the last 16 day(s) which contain
a total of 201 files changed, 4049 insertions(+), 2215 deletions(-).

The main changes are:

1) Add custom BPF allocator for JITs that pack multiple programs into a huge
   page to reduce iTLB pressure, from Song Liu.

2) Add __user tagging support in vmlinux BTF and utilize it from BPF
   verifier when generating loads, from Yonghong Song.

3) Add per-socket fast path check guarding from cgroup/BPF overhead when
   used by only some sockets, from Pavel Begunkov.

4) Continued libbpf deprecation work of APIs/features and removal of their
   usage from samples, selftests, libbpf & bpftool, from Andrii Nakryiko
   and various others.

5) Improve BPF instruction set documentation by adding byte swap
   instructions and cleaning up load/store section, from Christoph Hellwig.

6) Switch BPF preload infra to light skeleton and remove libbpf dependency
   from it, from Alexei Starovoitov.

7) Fix architecture-agnostic macros in libbpf for accessing syscall
   arguments from BPF progs for non-x86 architectures,
   from Ilya Leoshkevich.

8) Rework port members in struct bpf_sk_lookup and struct bpf_sock to be
   of 16-bit field with anonymous zero padding, from Jakub Sitnicki.

9) Add new bpf_copy_from_user_task() helper to read memory from a different
   task than current. Add ability to create sleepable BPF iterator progs,
   from Kenny Yu.

10) Implement XSK batching for ice's zero-copy driver used by AF_XDP and
    utilize TX batching API from XSK buffer pool, from Maciej Fijalkowski.

11) Generate temporary netns names for BPF selftests to avoid naming
    collisions, from Hangbin Liu.

12) Implement bpf_core_types_are_compat() with limited recursion for
    in-kernel usage, from Matteo Croce.

13) Simplify pahole version detection and finally enable CONFIG_DEBUG_INFO_DWARF5
    to be selected with CONFIG_DEBUG_INFO_BTF, from Nathan Chancellor.

14) Misc minor fixes to libbpf and selftests from various folks.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (126 commits)
  selftests/bpf: Cover 4-byte load from remote_port in bpf_sk_lookup
  bpf: Make remote_port field in struct bpf_sk_lookup 16-bit wide
  libbpf: Fix compilation warning due to mismatched printf format
  selftests/bpf: Test BPF_KPROBE_SYSCALL macro
  libbpf: Add BPF_KPROBE_SYSCALL macro
  libbpf: Fix accessing the first syscall argument on s390
  libbpf: Fix accessing the first syscall argument on arm64
  libbpf: Allow overriding PT_REGS_PARM1{_CORE}_SYSCALL
  selftests/bpf: Skip test_bpf_syscall_macro's syscall_arg1 on arm64 and s390
  libbpf: Fix accessing syscall arguments on riscv
  libbpf: Fix riscv register names
  libbpf: Fix accessing syscall arguments on powerpc
  selftests/bpf: Use PT_REGS_SYSCALL_REGS in bpf_syscall_macro
  libbpf: Add PT_REGS_SYSCALL_REGS macro
  selftests/bpf: Fix an endianness issue in bpf_syscall_macro test
  bpf: Fix bpf_prog_pack build HPAGE_PMD_SIZE
  bpf: Fix leftover header->pages in sparc and powerpc code.
  libbpf: Fix signedness bug in btf_dump_array_data()
  selftests/bpf: Do not export subtest as standalone test
  bpf, x86_64: Fail gracefully on bpf_jit_binary_pack_finalize failures
  ...
====================

Link: https://lore.kernel.org/r/20220209210050.8425-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-09 18:40:56 -08:00
Mauricio Vásquez da7af0aa20 bpftool: Fix strict mode calculation
"(__LIBBPF_STRICT_LAST - 1) & ~LIBBPF_STRICT_MAP_DEFINITIONS" is wrong
as it is equal to 0 (LIBBPF_STRICT_NONE). Let's use
"LIBBPF_STRICT_ALL & ~LIBBPF_STRICT_MAP_DEFINITIONS" now that the
previous commit makes it possible in libbpf.

Fixes: 93b8952d22 ("libbpf: deprecate legacy BPF map definitions")
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220207145052.124421-3-mauricio@kinvolk.io
2022-02-07 12:12:22 -08:00
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
Jakub Kicinski 77b1b8b43e Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2022-02-03

We've added 6 non-merge commits during the last 10 day(s) which contain
a total of 7 files changed, 11 insertions(+), 236 deletions(-).

The main changes are:

1) Fix BPF ringbuf to allocate its area with VM_MAP instead of VM_ALLOC
   flag which otherwise trips over KASAN, from Hou Tao.

2) Fix unresolved symbol warning in resolve_btfids due to LSM callback
   rename, from Alexei Starovoitov.

3) Fix a possible race in inc_misses_counter() when IRQ would trigger
   during counter update, from He Fengqing.

4) Fix tooling infra for cross-building with clang upon probing whether
   gcc provides the standard libraries, from Jean-Philippe Brucker.

5) Fix silent mode build for resolve_btfids, from Nathan Chancellor.

6) Drop unneeded and outdated lirc.h header copy from tooling infra as
   BPF does not require it anymore, from Sean Young.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  tools/resolve_btfids: Do not print any commands when building silently
  bpf: Use VM_MAP instead of VM_ALLOC for ringbuf
  tools: Ignore errors from `which' when searching a GCC toolchain
  tools headers UAPI: remove stale lirc.h
  bpf: Fix possible race in inc_misses_counter
  bpf: Fix renaming task_getsecid_subj->current_getsecid_subj.
====================

Link: https://lore.kernel.org/r/20220203155815.25689-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-03 13:42:38 -08:00
Andrii Nakryiko a9a8ac592e bpftool: Fix uninit variable compilation warning
Newer GCC complains about capturing the address of unitialized variable.
While there is nothing wrong with the code (the variable is filled out
by the kernel), initialize the variable anyway to make compiler happy.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220202225916.3313522-4-andrii@kernel.org
2022-02-03 16:32:25 +01:00
Andrii Nakryiko 1a56c18e6c bpftool: Stop supporting BPF offload-enabled feature probing
libbpf 1.0 is not going to support passing ifindex to BPF
prog/map/helper feature probing APIs. Remove the support for BPF offload
feature probing.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20220202225916.3313522-3-andrii@kernel.org
2022-02-03 16:32:25 +01:00
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
Delyan Kratunov 9cce53138d bpftool: Migrate from bpf_prog_test_run_xattr
bpf_prog_test_run is being deprecated in favor of the OPTS-based
bpf_prog_test_run_opts.

Signed-off-by: Delyan Kratunov <delyank@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220202235423.1097270-4-delyank@fb.com
2022-02-02 22:31:18 -08:00
Alexei Starovoitov c69f94a33d libbpf: Open code raw_tp_open and link_create commands.
Open code raw_tracepoint_open and link_create used by light skeleton
to be able to avoid full libbpf eventually.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220131220528.98088-4-alexei.starovoitov@gmail.com
2022-02-01 23:56:18 +01:00
Alexei Starovoitov 42d1d53fed libbpf: Add support for bpf iter in light skeleton.
bpf iterator programs should use bpf_link_create to attach instead of
bpf_raw_tracepoint_open like other tracing programs.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20220131220528.98088-2-alexei.starovoitov@gmail.com
2022-02-01 23:56:18 +01:00
Jakub Kicinski 72d044e4bf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-27 12:54:16 -08:00
Andrii Nakryiko 39748db1d6 bpftool: use preferred setters/getters instead of deprecated ones
Use bpf_program__type() instead of discouraged bpf_program__get_type().
Also switch to bpf_map__set_max_entries() instead of bpf_map__resize().

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220124194254.2051434-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-25 17:59:06 -08:00
Jakub Kicinski caaba96131 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-01-24

We've added 80 non-merge commits during the last 14 day(s) which contain
a total of 128 files changed, 4990 insertions(+), 895 deletions(-).

The main changes are:

1) Add XDP multi-buffer support and implement it for the mvneta driver,
   from Lorenzo Bianconi, Eelco Chaudron and Toke Høiland-Jørgensen.

2) Add unstable conntrack lookup helpers for BPF by using the BPF kfunc
   infra, from Kumar Kartikeya Dwivedi.

3) Extend BPF cgroup programs to export custom ret value to userspace via
   two helpers bpf_get_retval() and bpf_set_retval(), from YiFei Zhu.

4) Add support for AF_UNIX iterator batching, from Kuniyuki Iwashima.

5) Complete missing UAPI BPF helper description and change bpf_doc.py script
   to enforce consistent & complete helper documentation, from Usama Arif.

6) Deprecate libbpf's legacy BPF map definitions and streamline XDP APIs to
   follow tc-based APIs, from Andrii Nakryiko.

7) Support BPF_PROG_QUERY for BPF programs attached to sockmap, from Di Zhu.

8) Deprecate libbpf's bpf_map__def() API and replace users with proper getters
   and setters, from Christy Lee.

9) Extend libbpf's btf__add_btf() with an additional hashmap for strings to
   reduce overhead, from Kui-Feng Lee.

10) Fix bpftool and libbpf error handling related to libbpf's hashmap__new()
    utility function, from Mauricio Vásquez.

11) Add support to BTF program names in bpftool's program dump, from Raman Shukhau.

12) Fix resolve_btfids build to pick up host flags, from Connor O'Brien.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (80 commits)
  selftests, bpf: Do not yet switch to new libbpf XDP APIs
  selftests, xsk: Fix rx_full stats test
  bpf: Fix flexible_array.cocci warnings
  xdp: disable XDP_REDIRECT for xdp frags
  bpf: selftests: add CPUMAP/DEVMAP selftests for xdp frags
  bpf: selftests: introduce bpf_xdp_{load,store}_bytes selftest
  net: xdp: introduce bpf_xdp_pointer utility routine
  bpf: generalise tail call map compatibility check
  libbpf: Add SEC name for xdp frags programs
  bpf: selftests: update xdp_adjust_tail selftest to include xdp frags
  bpf: test_run: add xdp_shared_info pointer in bpf_test_finish signature
  bpf: introduce frags support to bpf_prog_test_run_xdp()
  bpf: move user_size out of bpf_test_init
  bpf: add frags support to xdp copy helpers
  bpf: add frags support to the bpf_xdp_adjust_tail() API
  bpf: introduce bpf_xdp_get_buff_len helper
  net: mvneta: enable jumbo frames if the loaded XDP program support frags
  bpf: introduce BPF_F_XDP_HAS_FRAGS flag in prog_flags loading the ebpf program
  net: mvneta: add frags support to XDP_TX
  xdp: add frags support to xdp_return_{buff/frame}
  ...
====================

Link: https://lore.kernel.org/r/20220124221235.18993-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-24 15:42:29 -08:00
Linus Torvalds dd81e1c7d5 powerpc fixes for 5.17 #2
- A series of bpf fixes, including an oops fix and some codegen fixes.
 
  - Fix a regression in syscall_get_arch() for compat processes.
 
  - Fix boot failure on some 32-bit systems with KASAN enabled.
 
  - A couple of other build/minor fixes.
 
 Thanks to: Athira Rajeev, Christophe Leroy, Dmitry V. Levin, Jiri Olsa, Johan Almbladh,
 Maxime Bizon, Naveen N. Rao, Nicholas Piggin.
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Merge tag 'powerpc-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:

 - A series of bpf fixes, including an oops fix and some codegen fixes.

 - Fix a regression in syscall_get_arch() for compat processes.

 - Fix boot failure on some 32-bit systems with KASAN enabled.

 - A couple of other build/minor fixes.

Thanks to Athira Rajeev, Christophe Leroy, Dmitry V. Levin, Jiri Olsa,
Johan Almbladh, Maxime Bizon, Naveen N. Rao, and Nicholas Piggin.

* tag 'powerpc-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Mask SRR0 before checking against the masked NIP
  powerpc/perf: Only define power_pmu_wants_prompt_pmi() for CONFIG_PPC64
  powerpc/32s: Fix kasan_init_region() for KASAN
  powerpc/time: Fix build failure due to do_hard_irq_enable() on PPC32
  powerpc/audit: Fix syscall_get_arch()
  powerpc64/bpf: Limit 'ldbrx' to processors compliant with ISA v2.06
  tools/bpf: Rename 'struct event' to avoid naming conflict
  powerpc/bpf: Update ldimm64 instructions during extra pass
  powerpc32/bpf: Fix codegen for bpf-to-bpf calls
  bpf: Guard against accessing NULL pt_regs in bpf_get_task_stack()
2022-01-23 17:52:42 +02:00
Andrii Nakryiko c86575ecca bpftool: use new API for attaching XDP program
Switch to new bpf_xdp_attach() API to avoid deprecation warnings.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220120061422.2710637-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-20 21:22:02 -08:00
Andrii Nakryiko 93b8952d22 libbpf: deprecate legacy BPF map definitions
Enact deprecation of legacy BPF map definition in SEC("maps") ([0]). For
the definitions themselves introduce LIBBPF_STRICT_MAP_DEFINITIONS flag
for libbpf strict mode. If it is set, error out on any struct
bpf_map_def-based map definition. If not set, libbpf will print out
a warning for each legacy BPF map to raise awareness that it goes away.

For any use of BPF_ANNOTATE_KV_PAIR() macro providing a legacy way to
associate BTF key/value type information with legacy BPF map definition,
warn through libbpf's pr_warn() error message (but don't fail BPF object
open).

BPF-side struct bpf_map_def is marked as deprecated. User-space struct
bpf_map_def has to be used internally in libbpf, so it is left
untouched. It should be enough for bpf_map__def() to be marked
deprecated to raise awareness that it goes away.

bpftool is an interesting case that utilizes libbpf to open BPF ELF
object to generate skeleton. As such, even though bpftool itself uses
full on strict libbpf mode (LIBBPF_STRICT_ALL), it has to relax it a bit
for BPF map definition handling to minimize unnecessary disruptions. So
opt-out of LIBBPF_STRICT_MAP_DEFINITIONS for bpftool. User's code that
will later use generated skeleton will make its own decision whether to
enforce LIBBPF_STRICT_MAP_DEFINITIONS or not.

There are few tests in selftests/bpf that are consciously using legacy
BPF map definitions to test libbpf functionality. For those, temporary
opt out of LIBBPF_STRICT_MAP_DEFINITIONS mode for the duration of those
tests.

  [0] Closes: https://github.com/libbpf/libbpf/issues/272

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220120060529.1890907-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-20 21:19:05 -08:00
Linus Torvalds f4484d138b Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:
 "55 patches.

  Subsystems affected by this patch series: percpu, procfs, sysctl,
  misc, core-kernel, get_maintainer, lib, checkpatch, binfmt, nilfs2,
  hfs, fat, adfs, panic, delayacct, kconfig, kcov, and ubsan"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (55 commits)
  lib: remove redundant assignment to variable ret
  ubsan: remove CONFIG_UBSAN_OBJECT_SIZE
  kcov: fix generic Kconfig dependencies if ARCH_WANTS_NO_INSTR
  lib/Kconfig.debug: make TEST_KMOD depend on PAGE_SIZE_LESS_THAN_256KB
  btrfs: use generic Kconfig option for 256kB page size limit
  arch/Kconfig: split PAGE_SIZE_LESS_THAN_256KB from PAGE_SIZE_LESS_THAN_64KB
  configs: introduce debug.config for CI-like setup
  delayacct: track delays from memory compact
  Documentation/accounting/delay-accounting.rst: add thrashing page cache and direct compact
  delayacct: cleanup flags in struct task_delay_info and functions use it
  delayacct: fix incomplete disable operation when switch enable to disable
  delayacct: support swapin delay accounting for swapping without blkio
  panic: remove oops_id
  panic: use error_report_end tracepoint on warnings
  fs/adfs: remove unneeded variable make code cleaner
  FAT: use io_schedule_timeout() instead of congestion_wait()
  hfsplus: use struct_group_attr() for memcpy() region
  nilfs2: remove redundant pointer sbufs
  fs/binfmt_elf: use PT_LOAD p_align values for static PIE
  const_structs.checkpatch: add frequently used ops structs
  ...
2022-01-20 10:41:01 +02:00
Yafang Shao 4cfb943537 tools/bpf/bpftool/skeleton: replace bpf_probe_read_kernel with bpf_probe_read_kernel_str to get task comm
bpf_probe_read_kernel_str() will add a nul terminator to the dst, then
we don't care about if the dst size is big enough.

Link: https://lkml.kernel.org/r/20211120112738.45980-7-laoar.shao@gmail.com
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: Michal Miroslaw <mirq-linux@rere.qmqm.pl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-20 08:52:53 +02:00
Raman Shukhau b662000aff bpftool: Adding support for BTF program names
`bpftool prog list` and other bpftool subcommands that show
BPF program names currently get them from bpf_prog_info.name.
That field is limited to 16 (BPF_OBJ_NAME_LEN) chars which leads
to truncated names since many progs have much longer names.

The idea of this change is to improve all bpftool commands that
output prog name so that bpftool uses info from BTF to print
program names if available.

It tries bpf_prog_info.name first and fall back to btf only if
the name is suspected to be truncated (has 15 chars length).

Right now `bpftool p show id <id>` returns capped prog name

<id>: kprobe  name example_cap_cap  tag 712e...
...

With this change it would return

<id>: kprobe  name example_cap_capable  tag 712e...
...

Note, other commands that print prog names (e.g. "bpftool
cgroup tree") are also addressed in this change.

Signed-off-by: Raman Shukhau <ramasha@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220119100255.1068997-1-ramasha@fb.com
2022-01-19 10:04:41 -08:00
Naveen N. Rao 88a71086c4 tools/bpf: Rename 'struct event' to avoid naming conflict
On ppc64le, trying to build bpf seltests throws the below warning:
  In file included from runqslower.bpf.c:5:
  ./runqslower.h:7:8: error: redefinition of 'event'
  struct event {
	 ^
  /home/naveen/linux/tools/testing/selftests/bpf/tools/build/runqslower/vmlinux.h:156602:8:
  note: previous definition is here
  struct event {
	 ^

This happens since 'struct event' is defined in
drivers/net/ethernet/alteon/acenic.h . Rename the one in runqslower to a
more appropriate 'runq_event' to avoid the naming conflict.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c13cb3767d26257ca4387b8296b632b433a58db6.1641468127.git.naveen.n.rao@linux.vnet.ibm.com
2022-01-15 12:21:25 +11:00
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
Christy Lee 3c28919f06 bpftool: Stop using bpf_map__def() API
libbpf bpf_map__def() API is being deprecated, replace bpftool's
usage with the appropriate getters and setters

Signed-off-by: Christy Lee <christylee@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220108004218.355761-3-christylee@fb.com
2022-01-12 17:01:38 -08:00
Wei Fu 0991f6a38f bpftool: Only set obj->skeleton on complete success
After `bpftool gen skeleton`, the ${bpf_app}.skel.h will provide that
${bpf_app_name}__open helper to load bpf. If there is some error
like ENOMEM, the ${bpf_app_name}__open will rollback(free) the allocated
object, including `bpf_object_skeleton`.

Since the ${bpf_app_name}__create_skeleton set the obj->skeleton first
and not rollback it when error, it will cause double-free in
${bpf_app_name}__destory at ${bpf_app_name}__open. Therefore, we should
set the obj->skeleton before return 0;

Fixes: 5dc7a8b211 ("bpftool, selftests/bpf: Embed object file inside skeleton")
Signed-off-by: Wei Fu <fuweid89@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220108084008.1053111-1-fuweid89@gmail.com
2022-01-12 17:01:38 -08:00
Mauricio Vásquez 622a5b582c bpftool: Fix error check when calling hashmap__new()
hashmap__new() encodes errors with ERR_PTR(), hence it's not valid to
check the returned pointer against NULL and IS_ERR() has to be used
instead.

libbpf_get_error() can't be used in this case as hashmap__new() is not
part of the public libbpf API and it'll continue using ERR_PTR() after
libbpf 1.0.

Fixes: 8f184732b6 ("bpftool: Switch to libbpf's hashmap for pinned paths of BPF objects")
Fixes: 2828d0d75b ("bpftool: Switch to libbpf's hashmap for programs/maps in BTF listing")
Fixes: d6699f8e0f ("bpftool: Switch to libbpf's hashmap for PIDs/names references")
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220107152620.192327-2-mauricio@kinvolk.io
2022-01-12 17:01:36 -08:00
Christy Lee 9855c131b9 libbpf 1.0: Deprecate bpf_map__is_offload_neutral()
Deprecate bpf_map__is_offload_neutral(). It’s most probably broken
already. PERF_EVENT_ARRAY isn’t the only map that’s not suitable
for hardware offloading. Applications can directly check map type
instead.

  [0] Closes: https://github.com/libbpf/libbpf/issues/306

Signed-off-by: Christy Lee <christylee@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220105000601.2090044-1-christylee@fb.com
2022-01-05 16:09:06 -08:00
Paul Chaignon 0fd800b245 bpftool: Probe for instruction set extensions
This patch introduces new probes to check whether the kernel supports
instruction set extensions v2 and v3. The first introduced eBPF
instructions BPF_J{LT,LE,SLT,SLE} in commit 92b31a9af7 ("bpf: add
BPF_J{LT,LE,SLT,SLE} instructions"). The second introduces 32-bit
variants of all jump instructions in commit 092ed0968b ("bpf:
verifier support JMP32").

These probes are useful for userspace BPF projects that want to use newer
instruction set extensions on newer kernels, to reduce the programs'
sizes or their complexity. LLVM already provides an mcpu=probe option to
automatically probe the kernel and select the newest-supported
instruction set extension. That is however not flexible enough for all
use cases. For example, in Cilium, we only want to use the v3
instruction set extension on v5.10+, even though it is supported on all
kernels v5.1+.

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/3bfedcd9898c1f41ac67ca61f144fec84c6c3a92.1641314075.git.paul@isovalent.com
2022-01-05 13:31:40 +01:00
Paul Chaignon c04fb2b0bd bpftool: Probe for bounded loop support
This patch introduces a new probe to check whether the verifier supports
bounded loops as introduced in commit 2589726d12 ("bpf: introduce
bounded loops"). This patch will allow BPF users such as Cilium to probe
for loop support on startup and only unconditionally unroll loops on
older kernels.

The results are displayed as part of the miscellaneous section, as shown
below.

  $ bpftool feature probe | grep loops
  Bounded loop support is available
  $ bpftool feature probe macro | grep LOOPS
  #define HAVE_BOUNDED_LOOPS
  $ bpftool feature probe -j | jq .misc
  {
    "have_large_insn_limit": true,
    "have_bounded_loops": true
  }

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/f7807c0b27d79f48e71de7b5a99c680ca4bd0151.1641314075.git.paul@isovalent.com
2022-01-05 13:31:40 +01:00
Paul Chaignon b22bf1b997 bpftool: Refactor misc. feature probe
There is currently a single miscellaneous feature probe,
HAVE_LARGE_INSN_LIMIT, to check for the 1M instructions limit in the
verifier. Subsequent patches will add additional miscellaneous probes,
which follow the same pattern at the existing probe. This patch
therefore refactors the probe to avoid code duplication in subsequent
patches.

The BPF program type and the checked error numbers in the
HAVE_LARGE_INSN_LIMIT probe are changed to better generalize to other
probes. The feature probe retains its current behavior despite those
changes.

Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/956c9329a932c75941194f91790d01f31dfbe01b.1641314075.git.paul@isovalent.com
2022-01-05 13:31:40 +01:00
Paul Chaignon 1a1a0b0364 bpftool: Enable line buffering for stdout
The output of bpftool prog tracelog is currently buffered, which is
inconvenient when piping the output into other commands. A simple
tracelog | grep will typically not display anything. This patch fixes it
by enabling line buffering on stdout for the whole bpftool binary.

Fixes: 30da46b5dc ("tools: bpftool: add a command to dump the trace pipe")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Paul Chaignon <paul@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211220214528.GA11706@Mem
2021-12-21 15:44:51 -08:00
Andrii Nakryiko e967a20a8f bpftool: Reimplement large insn size limit feature probing
Reimplement bpf_probe_large_insn_limit() in bpftool, as that libbpf API
is scheduled for deprecation in v0.8.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/bpf/20211217171202.3352835-4-andrii@kernel.org
2021-12-17 23:11:13 +01:00
Jean-Philippe Brucker bb7b75e860 tools/runqslower: Enable cross-building with clang
Cross-building using clang requires passing the "-target" flag rather
than using the CROSS_COMPILE prefix. Makefile.include transforms
CROSS_COMPILE into CLANG_CROSS_FLAGS. Add them to CFLAGS, and erase
CROSS_COMPILE for the bpftool build, since it needs to be executed on
the host.

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/20211216163842.829836-6-jean-philippe@linaro.org
2021-12-16 12:15:05 -08:00
Jean-Philippe Brucker bdadbb44c9 bpftool: Enable cross-building with clang
Cross-building using clang requires passing the "-target" flag rather
than using the CROSS_COMPILE prefix. Makefile.include transforms
CROSS_COMPILE into CLANG_CROSS_FLAGS, and adds that to CFLAGS. Remove
the cross flags for the bootstrap bpftool, and erase the CROSS_COMPILE
flag for the bootstrap libbpf.

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/20211216163842.829836-5-jean-philippe@linaro.org
2021-12-16 12:15:05 -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
Andrii Nakryiko b59e4ce8bc bpftool: Switch bpf_object__load_xattr() to bpf_object__load()
Switch all the uses of to-be-deprecated bpf_object__load_xattr() into
a simple bpf_object__load() calls with optional log_level passed through
open_opts.kernel_log_level, if -d option is specified.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211209193840.1248570-13-andrii@kernel.org
2021-12-10 15:29:18 -08:00
Jakub Kicinski 3150a73366 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09 13:23:02 -08:00
Alexei Starovoitov 942df4dc5e bpftool: Add debug mode for gen_loader.
Make -d flag functional for gen_loader style program loading.

For example:
$ bpftool prog load -L -d test_d_path.o
... // will print:
libbpf: loading ./test_d_path.o
libbpf: elf: section(3) fentry/security_inode_getattr, size 280, link 0, flags 6, type=1
...
libbpf: prog 'prog_close': found data map 0 (test_d_p.bss, sec 7, off 0) for insn 30
libbpf: gen: load_btf: size 5376
libbpf: gen: map_create: test_d_p.bss idx 0 type 2 value_type_id 118
libbpf: map 'test_d_p.bss': created successfully, fd=0
libbpf: gen: map_update_elem: idx 0
libbpf: sec 'fentry/filp_close': found 1 CO-RE relocations
libbpf: record_relo_core: prog 1 insn[15] struct file 0:1 final insn_idx 15
libbpf: gen: prog_load: type 26 insns_cnt 35 progi_idx 0
libbpf: gen: find_attach_tgt security_inode_getattr 12
libbpf: gen: prog_load: type 26 insns_cnt 37 progi_idx 1
libbpf: gen: find_attach_tgt filp_close 12
libbpf: gen: finish 0
... // at this point libbpf finished generating loader program
   0: (bf) r6 = r1
   1: (bf) r1 = r10
   2: (07) r1 += -136
   3: (b7) r2 = 136
   4: (b7) r3 = 0
   5: (85) call bpf_probe_read_kernel#113
   6: (05) goto pc+104
... // this is the assembly dump of the loader program
 390: (63) *(u32 *)(r6 +44) = r0
 391: (18) r1 = map[idx:0]+5584
 393: (61) r0 = *(u32 *)(r1 +0)
 394: (63) *(u32 *)(r6 +24) = r0
 395: (b7) r0 = 0
 396: (95) exit
err 0  // the loader program was loaded and executed successfully
(null)
func#0 @0
...  // CO-RE in the kernel logs:
CO-RE relocating STRUCT file: found target candidate [500]
prog '': relo #0: kind <byte_off> (0), spec is [8] STRUCT file.f_path (0:1 @ offset 16)
prog '': relo #0: matching candidate #0 [500] STRUCT file.f_path (0:1 @ offset 16)
prog '': relo #0: patched insn #15 (ALU/ALU64) imm 16 -> 16
vmlinux_cand_cache:[11]file(500),
module_cand_cache:
... // verifier logs when it was checking test_d_path.o program:
R1 type=ctx expected=fp
0: R1=ctx(id=0,off=0,imm=0) R10=fp0
; int BPF_PROG(prog_close, struct file *file, void *id)
0: (79) r6 = *(u64 *)(r1 +0)
func 'filp_close' arg0 has btf_id 500 type STRUCT 'file'
1: R1=ctx(id=0,off=0,imm=0) R6_w=ptr_file(id=0,off=0,imm=0) R10=fp0
; pid_t pid = bpf_get_current_pid_tgid() >> 32;
1: (85) call bpf_get_current_pid_tgid#14

... // if there are multiple programs being loaded by the loader program
... // only the last program in the elf file will be printed, since
... // the same verifier log_buf is used for all PROG_LOAD commands.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211204194623.27779-1-alexei.starovoitov@gmail.com
2021-12-05 11:40:32 -08:00
Andrii Nakryiko a15d408b83 bpftool: Migrate off of deprecated bpf_create_map_xattr() API
Switch to bpf_map_create() API instead.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211201232824.3166325-4-andrii@kernel.org
2021-12-02 15:23:40 -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
Jakub Kicinski 50fc24944a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-18 13:13:16 -08:00
Quentin Monnet b623181520 bpftool: Update doc (use susbtitutions) and test_bpftool_synctypes.py
test_bpftool_synctypes.py helps detecting inconsistencies in bpftool
between the different list of types and options scattered in the
sources, the documentation, and the bash completion. For options that
apply to all bpftool commands, the script had a hardcoded list of
values, and would use them to check whether the man pages are
up-to-date. When writing the script, it felt acceptable to have this
list in order to avoid to open and parse bpftool's main.h every time,
and because the list of global options in bpftool doesn't change so
often.

However, this is prone to omissions, and we recently added a new
-l|--legacy option which was described in common_options.rst, but not
listed in the options summary of each manual page. The script did not
complain, because it keeps comparing the hardcoded list to the (now)
outdated list in the header file.

To address the issue, this commit brings the following changes:

- Options that are common to all bpftool commands (--json, --pretty, and
  --debug) are moved to a dedicated file, and used in the definition of
  a RST substitution. This substitution is used in the sources of all
  the man pages.

- This list of common options is updated, with the addition of the new
  -l|--legacy option.

- The script test_bpftool_synctypes.py is updated to compare:
    - Options specific to a command, found in C files, for the
      interactive help messages, with the same specific options from the
      relevant man page for that command.
    - Common options, checked just once: the list in main.h is
      compared with the new list in substitutions.rst.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-3-quentin@isovalent.com
2021-11-16 13:56:22 +01:00
Quentin Monnet 4344842836 bpftool: Add SPDX tags to RST documentation files
Most files in the kernel repository have a SPDX tags. The files that
don't have such a tag (or another license boilerplate) tend to fall
under the GPL-2.0 license. In the past, bpftool's Makefile (for example)
has been marked as GPL-2.0 for that reason, when in fact all bpftool is
dual-licensed.

To prevent a similar confusion from happening with the RST documentation
files for bpftool, let's explicitly mark all files as dual-licensed.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211115225844.33943-2-quentin@isovalent.com
2021-11-16 13:56:22 +01:00
Stanislav Fomichev e47d0bf800 bpftool: Add current libbpf_strict mode to version output
+ bpftool --legacy --version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool --version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --legacy --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool --help
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }
+ bpftool
Usage: bpftool [OPTIONS] OBJECT { COMMAND | help }
       bpftool batch file FILE
       bpftool version

       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }
       OPTIONS := { {-j|--json} [{-p|--pretty}] | {-d|--debug} | {-l|--legacy} |
                    {-V|--version} }

+ bpftool --legacy version
bpftool v5.15.0
features: libbfd, skeletons
+ bpftool version
bpftool v5.15.0
features: libbfd, libbpf_strict, skeletons

+ bpftool --json --legacy version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":false,"skeletons":true}}
+ bpftool --json version
{"version":"5.15.0","features":{"libbfd":true,"libbpf_strict":true,"skeletons":true}}

Suggested-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20211116000448.2918854-1-sdf@google.com
2021-11-16 10:32:50 +01:00
Jakub Kicinski a5bdc36354 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-11-15

We've added 72 non-merge commits during the last 13 day(s) which contain
a total of 171 files changed, 2728 insertions(+), 1143 deletions(-).

The main changes are:

1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to
   BTF such that BPF verifier will be able to detect misuse, from Yonghong Song.

2) Big batch of libbpf improvements including various fixes, future proofing APIs,
   and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko.

3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the
   programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush.

4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to
   ensure exception handling still works, from Russell King and Alan Maguire.

5) Add a new bpf_find_vma() helper for tracing to map an address to the backing
   file such as shared library, from Song Liu.

6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump,
   updating documentation and bash-completion among others, from Quentin Monnet.

7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as
   the API is heavily tailored around perf and is non-generic, from Dave Marchevsky.

8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an
   opt-out for more relaxed BPF program requirements, from Stanislav Fomichev.

9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
  bpftool: Use libbpf_get_error() to check error
  bpftool: Fix mixed indentation in documentation
  bpftool: Update the lists of names for maps and prog-attach types
  bpftool: Fix indent in option lists in the documentation
  bpftool: Remove inclusion of utilities.mak from Makefiles
  bpftool: Fix memory leak in prog_dump()
  selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning
  selftests/bpf: Fix an unused-but-set-variable compiler warning
  bpf: Introduce btf_tracing_ids
  bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs
  bpftool: Enable libbpf's strict mode by default
  docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
  selftests/bpf: Clarify llvm dependency with btf_tag selftest
  selftests/bpf: Add a C test for btf_type_tag
  selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c
  selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication
  selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests
  selftests/bpf: Test libbpf API function btf__add_type_tag()
  bpftool: Support BTF_KIND_TYPE_TAG
  libbpf: Support BTF_KIND_TYPE_TAG
  ...
====================

Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-15 08:49:23 -08:00
Hengqi Chen e5043894b2 bpftool: Use libbpf_get_error() to check error
Currently, LIBBPF_STRICT_ALL mode is enabled by default for
bpftool which means on error cases, some libbpf APIs would
return NULL pointers. This makes IS_ERR check failed to detect
such cases and result in segfault error. Use libbpf_get_error()
instead like we do in libbpf itself.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211115012436.3143318-1-hengqi.chen@gmail.com
2021-11-14 18:38:13 -08:00