From f7d72d0b3f438b881dba16c7c00493f16e41a821 Mon Sep 17 00:00:00 2001 From: Anton Protopopov Date: Sun, 19 Oct 2025 20:21:30 +0000 Subject: [PATCH] bpf: save the start of functions in bpf_prog_aux Introduce a new subprog_start field in bpf_prog_aux. This field may be used by JIT compilers wanting to know the real absolute xlated offset of the function being jitted. The func_info[func_id] may have served this purpose, but func_info may be NULL, so JIT compilers can't rely on it. Signed-off-by: Anton Protopopov Acked-by: Eduard Zingerman Link: https://lore.kernel.org/r/20251019202145.3944697-3-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov --- include/linux/bpf.h | 1 + kernel/bpf/verifier.c | 1 + 2 files changed, 2 insertions(+) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 204f9c759a41a..3bda915cd7a8e 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1623,6 +1623,7 @@ struct bpf_prog_aux { u32 ctx_arg_info_size; u32 max_rdonly_access; u32 max_rdwr_access; + u32 subprog_start; struct btf *attach_btf; struct bpf_ctx_arg_aux *ctx_arg_info; void __percpu *priv_stack_ptr; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 80c99ef4cac5f..4579082068cac 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -21607,6 +21607,7 @@ static int jit_subprogs(struct bpf_verifier_env *env) func[i]->aux->func_idx = i; /* Below members will be freed only at prog->aux */ func[i]->aux->btf = prog->aux->btf; + func[i]->aux->subprog_start = subprog_start; func[i]->aux->func_info = prog->aux->func_info; func[i]->aux->func_info_cnt = prog->aux->func_info_cnt; func[i]->aux->poke_tab = prog->aux->poke_tab; -- 2.47.3