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| author | Andrii Nakryiko <andrii@kernel.org> | 2023-03-17 15:44:27 -0700 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2023-03-17 15:46:03 -0700 |
| commit | 6cae5a7106e272e7908a1facdf519a307f93872d (patch) | |
| tree | dd3fb68a821169c52d13421de0ba528db0ce70ba /tools/lib/bpf/libbpf.c | |
| parent | 0f10f647f45545004ea50b73a7a7c5c3309ff286 (diff) | |
| parent | 95fdf6e313a981b0729886f86916190cb418b04c (diff) | |
Merge branch 'bpf: Add detection of kfuncs.'
Alexei Starovoitov says:
====================
From: Alexei Starovoitov <ast@kernel.org>
Allow BPF programs detect at load time whether particular kfunc exists.
Patch 1: Allow ld_imm64 to point to kfunc in the kernel.
Patch 2: Fix relocation of kfunc in ld_imm64 insn when kfunc is in kernel module.
Patch 3: Introduce bpf_ksym_exists() macro.
Patch 4: selftest.
NOTE: detection of kfuncs from light skeleton is not supported yet.
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a557718401e4..4c34fbd7b5be 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -7533,6 +7533,12 @@ static int bpf_object__resolve_ksym_func_btf_id(struct bpf_object *obj, ext->is_set = true; ext->ksym.kernel_btf_id = kfunc_id; ext->ksym.btf_fd_idx = mod_btf ? mod_btf->fd_array_idx : 0; + /* Also set kernel_btf_obj_fd to make sure that bpf_object__relocate_data() + * populates FD into ld_imm64 insn when it's used to point to kfunc. + * {kernel_btf_id, btf_fd_idx} -> fixup bpf_call. + * {kernel_btf_id, kernel_btf_obj_fd} -> fixup ld_imm64. + */ + ext->ksym.kernel_btf_obj_fd = mod_btf ? mod_btf->fd : 0; pr_debug("extern (func ksym) '%s': resolved to kernel [%d]\n", ext->name, kfunc_id); |