On Thu, Feb 3, 2022 at 4:55 PM Matteo Croce <mcroce@xxxxxxxxxxxxxxxxxxx> wrote: > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > @@ -13,6 +13,11 @@ > #define CREATE_TRACE_POINTS > #include "bpf_testmod-events.h" > > +typedef int (*func_proto_typedef___match)(long); > +typedef int (*func_proto_typedef___overflow)(func_proto_typedef___match); There is no need for "___flavor" on the kernel side of type definition. It makes the test confusing to read. > +func_proto_typedef___match funcp = NULL; > +func_proto_typedef___overflow funcp_of = NULL; We have BTF_TYPE_EMIT() macro to avoid unnecessary declaration. > +typedef int (*func_proto_typedef___match)(long); > +typedef int (*func_proto_typedef___overflow)(func_proto_typedef___match); With <=1 in the previous patch such single depth of func_proto was reaching the recursion limit. Hence the fix <=0 was necessary. I've also changed this test to: +typedef int (*func_proto_typedef)(long); +typedef int (*func_proto_typedef_nested1)(func_proto_typedef); +typedef int (*func_proto_typedef_nested2)(func_proto_typedef_nested1); in bpf_testmod.c and in progs/core_kern_overflow.c and bpf_core_type_exists(func_proto_typedef_nested2); to go above the limit. Also added bpf_core_type_exists(func_proto_typedef_nested1) to progs/core_kern.c to stay at the limit. Please see the result in bpf-next.
