On Tue, 2024-02-27 at 22:30 -0800, Alexei Starovoitov wrote: [...] > > > I meant that this helper can peek spi from R1 just like code in > > > is_state_visited() does currently. Forgoing the 'meta' completely. > > > > I see. > > You mean removing: > > meta->iter.spi = spi; > > meta->iter.frameno = reg->frameno; > > from process_iter_arg() and > > 'meta' arg from process_iter_next_call() as well then ? > > Ed, > > That was a bad idea. > I tried what you suggested with > static struct bpf_reg_state *get_iter_reg(struct bpf_verifier_env *env, > struct bpf_verifier_state > *st, int insn_idx) > > and implemented in v2. > It's buggy as can be seen in CI (I sloppy tested it before sending it > yesterday). > I'm going to go back to v1 approach. > process_iter_next_call() _has_ to use meta, > since caller saved regs already cleared by the time it's called. > And doing fake 'meta' in is_state_visited() is not a good idea. > It took me a few hours to debug this :( Well, that is unfortunate, sorry about that.
