On Fri, Dec 08, 2023 at 02:40:41PM +0100, Peter Zijlstra wrote: > On Fri, Dec 08, 2023 at 11:29:40AM +0100, Peter Zijlstra wrote: > > The only problem I now have is the one XXX, I'm not entirely sure what > > signature to use there. > > > @@ -119,6 +119,7 @@ int bpf_struct_ops_test_run(struct bpf_p > > op_idx = prog->expected_attach_type; > > err = bpf_struct_ops_prepare_trampoline(tlinks, link, > > &st_ops->func_models[op_idx], > > + /* XXX */ NULL, > > image, image + PAGE_SIZE); > > if (err < 0) > > goto out; > > Duh, that should ofcourse be something of dummy_ops_test_ret_fn type. > Let me go fix that. Next one.. bpf_obj_free_fields: field->kptr.dtor(xchg_field); The one that trips is bpf_cgroup_release(). objtool doesn't think the address of that function 'escapes' and 'helpfully' seals that function, and then BPF thinks it does escape and manages the above indirect call and *boom*. How can I tell which functions escape according to BPF such that I might teach objtool this?
