On Tue, Sep 21, 2021 at 11:06 PM Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> wrote: > > On Wed, Sep 22, 2021 at 05:33:26AM IST, Andrii Nakryiko wrote: > > > [...] > > > Hmm, good idea, I'd just need to fill in the BTF id dynamically at runtime, > > > but that should be possible. > > > > > > Though we still need to craft distinct calls (I am trying to test the limit > > > where insn->off is different for each case). Since we try to reuse index in both > > > gen_loader and libbpf, just generating same call 256 times would not be enough. > > > > You just need to generate one instruction with offset = 257 to test > > this. And separately one call with fd_array that has module BTF fd at > > fd_array[256] (to check that 256 is ok). Or am I missing something? > > > > That won't be enough, if I just pass insn->imm = id, insn->off = 257, it becomes > first descriptor in kfunc_tab and kfunc_btf_tab. The total limit is 256, and > they are kept in sorted order by based on id and off for the first, off for the > second. So 256 different offs are needed (imm may be same actually), so that > both fill up. Just to test the 256 limit? I don't think it's necessary. afaik there is no test that exercises the 64 map limit.
