linux-stable.git/tools/bpf, branch v6.0.6

bpftool: Clear errno after libcap's checks

2022-10-21T10:39:05+00:00

[ Upstream commit cea558855c39b7f1f02ff50dcf701ca6596bc964 ]

When bpftool is linked against libcap, the library runs a "constructor"
function to compute the number of capabilities of the running kernel
[0], at the beginning of the execution of the program. As part of this,
it performs multiple calls to prctl(). Some of these may fail, and set
errno to a non-zero value:

    # strace -e prctl ./bpftool version
    prctl(PR_CAPBSET_READ, CAP_MAC_OVERRIDE) = 1
    prctl(PR_CAPBSET_READ, 0x30 /* CAP_??? */) = -1 EINVAL (Invalid argument)
    prctl(PR_CAPBSET_READ, CAP_CHECKPOINT_RESTORE) = 1
    prctl(PR_CAPBSET_READ, 0x2c /* CAP_??? */) = -1 EINVAL (Invalid argument)
    prctl(PR_CAPBSET_READ, 0x2a /* CAP_??? */) = -1 EINVAL (Invalid argument)
    prctl(PR_CAPBSET_READ, 0x29 /* CAP_??? */) = -1 EINVAL (Invalid argument)
    ** fprintf added at the top of main(): we have errno == 1
    ./bpftool v7.0.0
    using libbpf v1.0
    features: libbfd, libbpf_strict, skeletons
    +++ exited with 0 +++

This has been addressed in libcap 2.63 [1], but until this version is
available everywhere, we can fix it on bpftool side.

Let's clean errno at the beginning of the main() function, to make sure
that these checks do not interfere with the batch mode, where we error
out if errno is set after a bpftool command.

  [0] https://git.kernel.org/pub/scm/libs/libcap/libcap.git/tree/libcap/cap_alloc.c?h=libcap-2.65#n20
  [1] https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=f25a1b7e69f7b33e6afb58b3e38f3450b7d2d9a0

Signed-off-by: Quentin Monnet 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20220815162205.45043-1-quentin@isovalent.com
Signed-off-by: Sasha Levin

bpftool: Fix wrong cgroup attach flags being assigned to effective progs

2022-10-21T10:38:12+00:00

[ Upstream commit bdcee1b0b0834d031c76a12209840afe949b048a ]

When root-cgroup attach multi progs and sub-cgroup attach a override prog,
bpftool will display incorrectly for the attach flags of the sub-cgroup’s
effective progs:

$ bpftool cgroup tree /sys/fs/cgroup effective
CgroupPath
ID       AttachType      AttachFlags     Name
/sys/fs/cgroup
6        cgroup_sysctl   multi           sysctl_tcp_mem
13       cgroup_sysctl   multi           sysctl_tcp_mem
/sys/fs/cgroup/cg1
20       cgroup_sysctl   override        sysctl_tcp_mem
6        cgroup_sysctl   override        sysctl_tcp_mem <- wrong
13       cgroup_sysctl   override        sysctl_tcp_mem <- wrong
/sys/fs/cgroup/cg1/cg2
20       cgroup_sysctl                   sysctl_tcp_mem
6        cgroup_sysctl                   sysctl_tcp_mem
13       cgroup_sysctl                   sysctl_tcp_mem

Attach flags is only valid for attached progs of this layer cgroup,
but not for effective progs. For querying with EFFECTIVE flags,
exporting attach flags does not make sense. So let's remove the
AttachFlags field and the associated logic. After this patch, the
above effective cgroup tree will show as bellow:

$ bpftool cgroup tree /sys/fs/cgroup effective
CgroupPath
ID       AttachType      Name
/sys/fs/cgroup
6        cgroup_sysctl   sysctl_tcp_mem
13       cgroup_sysctl   sysctl_tcp_mem
/sys/fs/cgroup/cg1
20       cgroup_sysctl   sysctl_tcp_mem
6        cgroup_sysctl   sysctl_tcp_mem
13       cgroup_sysctl   sysctl_tcp_mem
/sys/fs/cgroup/cg1/cg2
20       cgroup_sysctl   sysctl_tcp_mem
6        cgroup_sysctl   sysctl_tcp_mem
13       cgroup_sysctl   sysctl_tcp_mem

Fixes: b79c9fc9551b ("bpf: implement BPF_PROG_QUERY for BPF_LSM_CGROUP")
Fixes: a98bf57391a2 ("tools: bpftool: add support for reporting the effective cgroup progs")
Signed-off-by: Pu Lehui 
Link: https://lore.kernel.org/r/20220921104604.2340580-3-pulehui@huaweicloud.com
Signed-off-by: Martin KaFai Lau 
Signed-off-by: Sasha Levin

bpftool: Fix a wrong type cast in btf_dumper_int

2022-10-21T10:38:04+00:00

[ Upstream commit 7184aef9c0f7a81db8fd18d183ee42481d89bf35 ]

When `data` points to a boolean value, casting it to `int *` is problematic
and could lead to a wrong value being passed to `jsonw_bool`. Change the
cast to `bool *` instead.

Fixes: b12d6ec09730 ("bpf: btf: add btf print functionality")
Signed-off-by: Lam Thai 
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Quentin Monnet 
Acked-by: John Fastabend 
Link: https://lore.kernel.org/bpf/20220824225859.9038-1-lamthai@arista.com
Signed-off-by: Sasha Levin

bpftool: Complete libbfd feature detection

2022-08-10T13:44:01+00:00

Commit 6e8ccb4f624a7 ("tools/bpf: properly account for libbfd variations")
sets the linking flags depending on which flavor of the libbfd feature was
detected.

However, the flavors except libbfd cannot be detected, as they are not in
the feature list.

Complete the list of features to detect by adding libbfd-liberty and
libbfd-liberty-z.

Committer notes:

Adjust conflict with with:

  1e1613f64cc8a09d ("tools bpftool: Don't display disassembler-four-args feature test")
  600b7b26c07a070d ("tools bpftool: Fix compilation error with new binutils")

Fixes: 6e8ccb4f624a73c5 ("tools/bpf: properly account for libbfd variations")
Signed-off-by: Roberto Sassu 
Cc: Alexei Starovoitov 
Cc: Andres Freund 
Cc: Andrii Nakryiko 
Cc: bpf@vger.kernel.org
Cc: Daniel Borkmann 
Cc: Ingo Molnar 
Cc: John Fastabend 
Cc: KP Singh 
Cc: llvm@lists.linux.dev
Cc: Martin KaFai Lau 
Cc: Nathan Chancellor 
Cc: Nick Desaulniers 
Cc: Nick Terrell 
Cc: Peter Zijlstra 
Cc: Quentin Monnet 
Cc: Song Liu 
Cc: Stanislav Fomichev 
Link: https://lore.kernel.org/r/20220719170555.2576993-2-roberto.sassu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo

Merge tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

2022-08-06T16:36:08+00:00

Pull perf tools updates from Arnaldo Carvalho de Melo:

 - Introduce 'perf lock contention' subtool, using new lock contention
   tracepoints and using BPF for in kernel aggregation and then
   userspace processing using the perf tooling infrastructure for
   resolving symbols, target specification, etc.

   Since the new lock contention tracepoints don't provide lock names,
   get up to 8 stack traces and display the first non-lock function
   symbol name as a caller:

    $ perf lock report -F acquired,contended,avg_wait,wait_total

                    Name   acquired  contended     avg wait    total wait

     update_blocked_a...         40         40      3.61 us     144.45 us
     kernfs_fop_open+...          5          5      3.64 us      18.18 us
      _nohz_idle_balance          3          3      2.65 us       7.95 us
     tick_do_update_j...          1          1      6.04 us       6.04 us
      ep_scan_ready_list          1          1      3.93 us       3.93 us

   Supports the usual 'perf record' + 'perf report' workflow as well as
   a BCC/bpftrace like mode where you start the tool and then press
   control+C to get results:

     $ sudo perf lock contention -b
    ^C
    contended   total wait     max wait     avg wait         type   caller

            42    192.67 us     13.64 us      4.59 us     spinlock   queue_work_on+0x20
            23     85.54 us     10.28 us      3.72 us     spinlock   worker_thread+0x14a
             6     13.92 us      6.51 us      2.32 us        mutex   kernfs_iop_permission+0x30
             3     11.59 us     10.04 us      3.86 us        mutex   kernfs_dop_revalidate+0x3c
             1      7.52 us      7.52 us      7.52 us     spinlock   kthread+0x115
             1      7.24 us      7.24 us      7.24 us     rwlock:W   sys_epoll_wait+0x148
             2      7.08 us      3.99 us      3.54 us     spinlock   delayed_work_timer_fn+0x1b
             1      6.41 us      6.41 us      6.41 us     spinlock   idle_balance+0xa06
             2      2.50 us      1.83 us      1.25 us        mutex   kernfs_iop_lookup+0x2f
             1      1.71 us      1.71 us      1.71 us        mutex   kernfs_iop_getattr+0x2c
    ...

 - Add new 'perf kwork' tool to trace time properties of kernel work
   (such as softirq, and workqueue), uses eBPF skeletons to collect info
   in kernel space, aggregating data that then gets processed by the
   userspace tool, e.g.:

    # perf kwork report

     Kwork Name      | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
    ----------------------------------------------------------------------------------------------------
     nvme0q5:130     | 004 |      1.101 ms |    49 |    0.051 ms |    26035.056403 s |  26035.056455 s |
     amdgpu:162      | 002 |      0.176 ms |     9 |    0.046 ms |    26035.268020 s |  26035.268066 s |
     nvme0q24:149    | 023 |      0.161 ms |    55 |    0.009 ms |    26035.655280 s |  26035.655288 s |
     nvme0q20:145    | 019 |      0.090 ms |    33 |    0.014 ms |    26035.939018 s |  26035.939032 s |
     nvme0q31:156    | 030 |      0.075 ms |    21 |    0.010 ms |    26035.052237 s |  26035.052247 s |
     nvme0q8:133     | 007 |      0.062 ms |    12 |    0.021 ms |    26035.416840 s |  26035.416861 s |
     nvme0q6:131     | 005 |      0.054 ms |    22 |    0.010 ms |    26035.199919 s |  26035.199929 s |
     nvme0q19:144    | 018 |      0.052 ms |    14 |    0.010 ms |    26035.110615 s |  26035.110625 s |
     nvme0q7:132     | 006 |      0.049 ms |    13 |    0.007 ms |    26035.125180 s |  26035.125187 s |
     nvme0q18:143    | 017 |      0.033 ms |    14 |    0.007 ms |    26035.169698 s |  26035.169705 s |
     nvme0q17:142    | 016 |      0.013 ms |     1 |    0.013 ms |    26035.565147 s |  26035.565160 s |
     enp5s0-rx-0:164 | 006 |      0.004 ms |     4 |    0.002 ms |    26035.928882 s |  26035.928884 s |
     enp5s0-tx-0:166 | 008 |      0.003 ms |     3 |    0.002 ms |    26035.870923 s |  26035.870925 s |
    --------------------------------------------------------------------------------------------------------

   See commit log messages for more examples with extra options to limit
   the events time window, etc.

 - Add support for new AMD IBS (Instruction Based Sampling) features:

   With the DataSrc extensions, the source of data can be decoded among:
     - Local L3 or other L1/L2 in CCX.
     - A peer cache in a near CCX.
     - Data returned from DRAM.
     - A peer cache in a far CCX.
     - DRAM address map with "long latency" bit set.
     - Data returned from MMIO/Config/PCI/APIC.
     - Extension Memory (S-Link, GenZ, etc - identified by the CS target
       and/or address map at DF's choice).
     - Peer Agent Memory.

 - Support hardware tracing with Intel PT on guest machines, combining
   the traces with the ones in the host machine.

 - Add a "-m" option to 'perf buildid-list' to show kernel and modules
   build-ids, to display all of the information needed to do external
   symbolization of kernel stack traces, such as those collected by
   bpf_get_stackid().

 - Add arch TSC frequency information to perf.data file headers.

 - Handle changes in the binutils disassembler function signatures in
   perf, bpftool and bpf_jit_disasm (Acked by the bpftool maintainer).

 - Fix building the perf perl binding with the newest gcc in distros
   such as fedora rawhide, where some new warnings were breaking the
   build as perf uses -Werror.

 - Add 'perf test' entry for branch stack sampling.

 - Add ARM SPE system wide 'perf test' entry.

 - Add user space counter reading tests to 'perf test'.

 - Build with python3 by default, if available.

 - Add python converter script for the vendor JSON event files.

 - Update vendor JSON files for most Intel cores.

 - Add vendor JSON File for Intel meteorlake.

 - Add Arm Cortex-A78C and X1C JSON vendor event files.

 - Add workaround to symbol address reading from ELF files without phdr,
   falling back to the previoous equation.

 - Convert legacy map definition to BTF-defined in the perf BPF script
   test.

 - Rework prologue generation code to stop using libbpf deprecated APIs.

 - Add default hybrid events for 'perf stat' on x86.

 - Add topdown metrics in the default 'perf stat' on the hybrid machines
   (big/little cores).

 - Prefer sampled CPU when exporting JSON in 'perf data convert'

 - Fix ('perf stat CSV output linter') and ("Check branch stack
   sampling") 'perf test' entries on s390.

* tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (169 commits)
  perf stat: Refactor __run_perf_stat() common code
  perf lock: Print the number of lost entries for BPF
  perf lock: Add --map-nr-entries option
  perf lock: Introduce struct lock_contention
  perf scripting python: Do not build fail on deprecation warnings
  genelf: Use HAVE_LIBCRYPTO_SUPPORT, not the never defined HAVE_LIBCRYPTO
  perf build: Suppress openssl v3 deprecation warnings in libcrypto feature test
  perf parse-events: Break out tracepoint and printing
  perf parse-events: Don't #define YY_EXTRA_TYPE
  tools bpftool: Don't display disassembler-four-args feature test
  tools bpftool: Fix compilation error with new binutils
  tools bpf_jit_disasm: Don't display disassembler-four-args feature test
  tools bpf_jit_disasm: Fix compilation error with new binutils
  tools perf: Fix compilation error with new binutils
  tools include: add dis-asm-compat.h to handle version differences
  tools build: Don't display disassembler-four-args feature test
  tools build: Add feature test for init_disassemble_info API changes
  perf test: Add ARM SPE system wide test
  perf tools: Rework prologue generation code
  perf bpf: Convert legacy map definition to BTF-defined
  ...

tools bpftool: Don't display disassembler-four-args feature test

2022-08-01T18:34:05+00:00

The feature check does not seem important enough to display.

Requested-by: Jiri Olsa 
Signed-off-by: Andres Freund 
Acked-by: Quentin Monnet 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexei Starovoitov 
Cc: Ben Hutchings 
Cc: Quentin Monnet 
Cc: Sedat Dilek 
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-9-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo

tools bpftool: Fix compilation error with new binutils

2022-08-01T18:32:46+00:00

binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpftool/jit_disasm.c, e.g. on debian
unstable.

Relevant binutils commit:

  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07

Wire up the feature test and switch to init_disassemble_info_compat(),
which were introduced in prior commits, fixing the compilation failure.

I verified that bpftool can still disassemble bpf programs, both with an
old and new dis-asm.h API. There are no output changes for plain and json
formats. When comparing the output from old binutils (2.35)
to new bintuils with the patch (upstream snapshot) there are a few output
differences, but they are unrelated to this patch. An example hunk is:

     2f:	pop    %r14
     31:	pop    %r13
     33:	pop    %rbx
  -  34:	leaveq
  -  35:	retq
  +  34:	leave
  +  35:	ret

Signed-off-by: Andres Freund 
Acked-by: Quentin Monnet 
Cc: Alexei Starovoitov 
Cc: Ben Hutchings 
Cc: Jiri Olsa 
Cc: Quentin Monnet 
Cc: Sedat Dilek 
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-8-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo

tools bpf_jit_disasm: Don't display disassembler-four-args feature test

2022-08-01T18:31:51+00:00

The feature check does not seem important enough to display.

Suggested-by: Jiri Olsa 
Signed-off-by: Andres Freund 
Acked-by: Quentin Monnet 
Cc: Alexei Starovoitov 
Cc: Ben Hutchings 
Cc: Daniel Borkmann 
Cc: Quentin Monnet 
Cc: Sedat Dilek 
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-7-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo

tools bpf_jit_disasm: Fix compilation error with new binutils

2022-08-01T18:30:48+00:00

binutils changed the signature of init_disassemble_info(), which now causes
compilation to fail for tools/bpf/bpf_jit_disasm.c, e.g. on debian
unstable.

Relevant binutils commit:

  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=60a3da00bd5407f07

Wire up the feature test and switch to init_disassemble_info_compat(),
which were introduced in prior commits, fixing the compilation failure.

I verified that bpf_jit_disasm can still disassemble bpf programs, both
with the old and new dis-asm.h API. With old binutils there's no change in
output before/after this patch. When comparing the output from old
binutils (2.35) to new bintuils with the patch (upstream snapshot) there
are a few output differences, but they are unrelated to this patch. An
example hunk is:

     f4:	mov    %r14,%rsi
     f7:	mov    %r15,%rdx
     fa:	mov    $0x2a,%ecx
  -  ff:	callq  0xffffffffea8c4988
  +  ff:	call   0xffffffffea8c4988
    104:	test   %rax,%rax
    107:	jge    0x0000000000000110
    109:	xor    %eax,%eax
  - 10b:	jmpq   0x0000000000000073
  + 10b:	jmp    0x0000000000000073
    110:	cmp    $0x16,%rax

However, I had to use an older kernel to generate the bpf_jit_enabled =
2 output, as that has been broken since 5.18 / 1022a5498f6f745c ("bpf,
x86_64: Use bpf_jit_binary_pack_alloc").

  https://lore.kernel.org/20220703030210.pmjft7qc2eajzi6c@alap3.anarazel.de

Signed-off-by: Andres Freund 
Acked-by: Quentin Monnet 
Cc: Alexei Starovoitov 
Cc: Ben Hutchings 
Cc: Daniel Borkmann 
Cc: Jiri Olsa 
Cc: Quentin Monnet 
Cc: Sedat Dilek 
Cc: bpf@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220622181918.ykrs5rsnmx3og4sv@alap3.anarazel.de
Link: https://lore.kernel.org/r/20220801013834.156015-6-andres@anarazel.de
Signed-off-by: Arnaldo Carvalho de Melo

bpftool: Don't try to return value from void function in skeleton

2022-07-29T17:43:14+00:00

A skeleton generated by bpftool previously contained a return followed
by an expression in OBJ_NAME__detach(), which has return type void. This
did not hurt, the bpf_object__detach_skeleton() called there returns
void itself anyway, but led to a warning when compiling with e.g.
-pedantic.

Signed-off-by: Jörn-Thorben Hinz 
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/bpf/20220726133203.514087-1-jthinz@mailbox.tu-berlin.de