On Wed, May 24, 2023, at 05:05, Yonghong Song wrote: > On 5/23/23 12:43 PM, Arnd Bergmann wrote: >> From: Arnd Bergmann <arnd@xxxxxxxx> >> >> This function has no callers and no declaration when CONFIG_BPF_JIT_ALWAYS_ON >> is enabled: >> >> kernel/bpf/core.c:2075:6: error: no previous prototype for 'bpf_patch_call_args' [-Werror=missing-prototypes] > > If CONFIG_BPF_JIT_ALWAYS_ON is enabled, the definition of > bpf_patch_call_args should be invisible. Maybe I missed something. > Could you list *ALL& bpf related config options in your setup > so people can reproduce you above error messages? Sorry, my mistake. I've reworded the changelog now to fix this: | This function is only used when CONFIG_BPF_JIT_ALWAYS_ON is disabled, | but CONFIG_BPF_SYSCALL is enabled. When both are turned off, the | prototype is missing but the unused function is still compiled, | as seen from this W=1 warning: | | kernel/bpf/core.c:2075:6: error: no previous prototype for 'bpf_patch_call_args' [-Werror=missing-prototypes] | | Add a matching #ifdef for the definition to leave it out. If this makes sense now, I'll send out a v3. Arnd