Revert "bpf: Add support to inline bpf_get_func_ip helper on x86"

This reverts commit 97ee4d20ee67eb462581a7af01442de6586e390b.

Following change is adding more complexity to bpf_get_func_ip
helper for kprobe_multi programs, which can't be inlined easily.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20220321070113.1449167-2-jolsa@kernel.org

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 6347dcd..571ccd7 100644 (file)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -13698,7 +13698,7 @@ patch_map_ops_generic:
                        continue;
                }
 
-               /* Implement tracing bpf_get_func_ip inline. */
+               /* Implement bpf_get_func_ip inline. */
                if (prog_type == BPF_PROG_TYPE_TRACING &&
                    insn->imm == BPF_FUNC_get_func_ip) {
                        /* Load IP address from ctx - 16 */
@@ -13713,25 +13713,6 @@ patch_map_ops_generic:
                        continue;
                }
 
-#ifdef CONFIG_X86
-               /* Implement kprobe_multi bpf_get_func_ip inline. */
-               if (prog_type == BPF_PROG_TYPE_KPROBE &&
-                   eatype == BPF_TRACE_KPROBE_MULTI &&
-                   insn->imm == BPF_FUNC_get_func_ip) {
-                       /* Load IP address from ctx (struct pt_regs) ip */
-                       insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1,
-                                                 offsetof(struct pt_regs, ip));
-
-                       new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, 1);
-                       if (!new_prog)
-                               return -ENOMEM;
-
-                       env->prog = prog = new_prog;
-                       insn      = new_prog->insnsi + i + delta;
-                       continue;
-               }
-#endif
-
 patch_call_imm:
                fn = env->ops->get_func_proto(insn->imm, env->prog);
                /* all functions that have prototype and verifier allowed

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 9a7b6be..52c2998 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1042,7 +1042,6 @@ static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
 
 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
 {
-       /* This helper call is inlined by verifier on x86. */
        return instruction_pointer(regs);
 }