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| author | Alexei Starovoitov <ast@kernel.org> | 2020-07-23 22:20:32 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-07-25 20:16:35 -0700 |
| commit | 90065c0647efd6e2ec8983a702c4ba813af51b93 (patch) | |
| tree | c87d99dabe2c42a178399bffc9c9e94c2be496a2 /include | |
| parent | 909e446b3204642bdb54ab2f225652be89d91268 (diff) | |
| parent | 346938e9380cc0b2ad8e2566389cdc570386fe22 (diff) | |
Merge branch 'fix-bpf_get_stack-with-PEBS'
Song Liu says:
====================
Calling get_perf_callchain() on perf_events from PEBS entries may cause
unwinder errors. To fix this issue, perf subsystem fetches callchain early,
and marks perf_events are marked with __PERF_SAMPLE_CALLCHAIN_EARLY.
Similar issue exists when BPF program calls get_perf_callchain() via
helper functions. For more information about this issue, please refer to
discussions in [1].
This set fixes this issue with helper proto bpf_get_stackid_pe and
bpf_get_stack_pe.
[1] https://lore.kernel.org/lkml/ED7B9430-6489-4260-B3C5-9CFA2E3AA87A@fb.com/
Changes v4 => v5:
1. Return -EPROTO instead of -EINVAL on PERF_EVENT_IOC_SET_BPF errors.
(Alexei)
2. Let libbpf print a hint message when PERF_EVENT_IOC_SET_BPF returns
-EPROTO. (Alexei)
Changes v3 => v4:
1. Fix error check logic in bpf_get_stackid_pe and bpf_get_stack_pe.
(Alexei)
2. Do not allow attaching BPF programs with bpf_get_stack|stackid to
perf_event with precise_ip > 0, but not proper callchain. (Alexei)
3. Add selftest get_stackid_cannot_attach.
Changes v2 => v3:
1. Fix handling of stackmap skip field. (Andrii)
2. Simplify the code in a few places. (Andrii)
Changes v1 => v2:
1. Simplify the design and avoid introducing new helper function. (Andrii)
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/bpf.h | 2 | ||||
| -rw-r--r-- | include/linux/filter.h | 3 |
2 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 4175cf1f4665..8357be349133 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1675,6 +1675,8 @@ extern const struct bpf_func_proto bpf_get_current_comm_proto; extern const struct bpf_func_proto bpf_get_stackid_proto; extern const struct bpf_func_proto bpf_get_stack_proto; extern const struct bpf_func_proto bpf_get_task_stack_proto; +extern const struct bpf_func_proto bpf_get_stackid_proto_pe; +extern const struct bpf_func_proto bpf_get_stack_proto_pe; extern const struct bpf_func_proto bpf_sock_map_update_proto; extern const struct bpf_func_proto bpf_sock_hash_update_proto; extern const struct bpf_func_proto bpf_get_current_cgroup_id_proto; diff --git a/include/linux/filter.h b/include/linux/filter.h index d07a6e973a7d..0a355b005bf4 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -533,7 +533,8 @@ struct bpf_prog { is_func:1, /* program is a bpf function */ kprobe_override:1, /* Do we override a kprobe? */ has_callchain_buf:1, /* callchain buffer allocated? */ - enforce_expected_attach_type:1; /* Enforce expected_attach_type checking at attach time */ + enforce_expected_attach_type:1, /* Enforce expected_attach_type checking at attach time */ + call_get_stack:1; /* Do we call bpf_get_stack() or bpf_get_stackid() */ enum bpf_prog_type type; /* Type of BPF program */ enum bpf_attach_type expected_attach_type; /* For some prog types */ u32 len; /* Number of filter blocks */ |