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The goal of the enum is to assist with available BPF features detection. Support for bpf_rdonly_cast to void* is the first feature listed in the enum. Here is an example usage: if (bpf_core_enum_value_exists(enum bpf_features, BPF_FEAT_RDONLY_CAST_TO_VOID)) ... bpf_rdonly_cast(..., 0) ... Signed-off-by: Eduard Zingerman --- kernel/bpf/verifier.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8fd65eb74051..01050d1f7389 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -44,6 +44,11 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = { #undef BPF_LINK_TYPE }; +enum bpf_features { + BPF_FEAT_RDONLY_CAST_TO_VOID = 0, + BPF_FEAT_TOTAL, +}; + struct bpf_mem_alloc bpf_global_percpu_ma; static bool bpf_global_percpu_ma_set; @@ -24436,6 +24441,8 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 u32 log_true_size; bool is_priv; + BTF_TYPE_EMIT(enum bpf_features); + /* no program is valid */ if (ARRAY_SIZE(bpf_verifier_ops) == 0) return -EINVAL; -- 2.47.1