Re: [PATCH bpf-next v4 03/12] bpf: selftests: Fix fentry test kfunc prototypes

[Daniel Xu]

On Mon, Jun 10, 2024 at 03:28:36PM GMT, Jiri Olsa wrote:
> On Sat, Jun 08, 2024 at 03:15:59PM -0600, Daniel Xu wrote:
> > The prototypes in progs/get_func_ip_test.c were not in line with how the
> > actual kfuncs are defined in net/bpf/test_run.c. This causes compilation
> > errors when kfunc prototypes are generated from BTF.
> > 
> > Fix by aligning with actual kfunc definitions.
> > 
> > Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
> > ---
> >  .../testing/selftests/bpf/progs/get_func_ip_test.c | 14 +++++++-------
> >  1 file changed, 7 insertions(+), 7 deletions(-)
> > 
> > diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
> > index 8956eb78a226..a89596f7585d 100644
> > --- a/tools/testing/selftests/bpf/progs/get_func_ip_test.c
> > +++ b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
> > @@ -5,13 +5,13 @@
> >  
> >  char _license[] SEC("license") = "GPL";
> >  
> > -extern const void bpf_fentry_test1 __ksym;
> > -extern const void bpf_fentry_test2 __ksym;
> > -extern const void bpf_fentry_test3 __ksym;
> > -extern const void bpf_fentry_test4 __ksym;
> > -extern const void bpf_modify_return_test __ksym;
> > -extern const void bpf_fentry_test6 __ksym;
> > -extern const void bpf_fentry_test7 __ksym;
> > +extern int bpf_fentry_test1(int a) __ksym;
> 
> hum, the only registered one as kfunc is bpf_fentry_test1, to allow fmodret
> also there's bpf_fentry_test9 as kfunc, which AFAICS is not really needed

I think bpf_modify_return_test() is also registered. But otherwise yeah,
I think I was overaggressive here. Are you thinking something like this?


diff --git a/tools/testing/selftests/bpf/progs/get_func_ip_test.c b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
index a89596f7585d..2011cacdeb18 100644
--- a/tools/testing/selftests/bpf/progs/get_func_ip_test.c
+++ b/tools/testing/selftests/bpf/progs/get_func_ip_test.c
@@ -6,12 +6,11 @@
 char _license[] SEC("license") = "GPL";

 extern int bpf_fentry_test1(int a) __ksym;
-extern int bpf_fentry_test2(int a, __u64 b) __ksym;
-extern int bpf_fentry_test3(char a, int b, __u64 c) __ksym;
-extern int bpf_fentry_test4(void *a, char b, int c, __u64 d) __ksym;
 extern int bpf_modify_return_test(int a, int *b) __ksym;
-extern int bpf_fentry_test6(__u64 a, void *b, short c, int d, void *e, __u64 f) __ksym;
-extern int bpf_fentry_test7(struct bpf_fentry_test_t *arg) __ksym;
+
+extern const void bpf_fentry_test2 __ksym;
+extern const void bpf_fentry_test3 __ksym;
+extern const void bpf_fentry_test4 __ksym;

 extern bool CONFIG_X86_KERNEL_IBT __kconfig __weak;