On Mon, 17 Jun 2019 08:26:29 -0700 Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > On Mon, Jun 17, 2019 at 5:59 AM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > > > When CONFIG_MODULES is disabled, this function is never called: > > > > kernel/trace/bpf_trace.c:581:13: error: 'do_bpf_send_signal' defined but not used [-Werror=unused-function] > > hmm. it should work just fine without modules. > the bug is somewhere else. >From what I see, the only use of do_bpf_send_signal is within a #ifdef CONFIG_MODULES, which means that you will get a warning about a static unused when CONFIG_MODULES is not defined. In kernel/trace/bpf_trace.c we have: static void do_bpf_send_signal(struct irq_work *entry) [..] #ifdef CONFIG_MODULES [..] for_each_possible_cpu(cpu) { work = per_cpu_ptr(&send_signal_work, cpu); init_irq_work(&work->irq_work, do_bpf_send_signal); <-- on use of do_bpf_send_signal } [..] #endif /* CONFIG_MODULES */ The bug (really just a warning) reported is exactly here. -- Steve