On 1/7/26 10:59, Leon Hwang wrote: > On 1/7/26 07:12, Alexei Starovoitov wrote: >> On Fri Jun 26, 2026 at 8:43 AM PDT, Leon Hwang wrote: > [...] >> >> I don't think we need such fallback in patch [3].
Sorry, it seems I misunderstood the 'patch [3]' as the patch #3 of this series. Will discuss the fallback further in the sibling thread: https://lore.kernel.org/bpf/[email protected]/. Thanks, Leon > > Do you mean we can add the internal BPF_ADDR_PERCPU insn support to the > interpreter? > > See my reply in "PROBLEM: BPF interpreter fallback after JIT compilation > of BPF_ADDR_PERCPU leads to kernel panic" thread [1]. > > [1] > https://lore.kernel.org/bpf/[email protected]/ > >> >> And approach taken by this set also doesn't scale, since it splits >> the verifier/JIT logic into core.c which will be hard to keep consistent. >> I think we need another bit like jit_requested in prog like 'must_jit' >> that the verifier set for addr_space_cast, kfuncs and the rest. >> >> Then the core.c change will be: >> diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c >> index 649cce41e13f..5126a43c1b81 100644 >> --- a/kernel/bpf/core.c >> +++ b/kernel/bpf/core.c >> @@ -2620,7 +2620,7 @@ struct bpf_prog *__bpf_prog_select_runtime(struct >> bpf_verifier_env *env, struct >> goto finalize; >> >> if (IS_ENABLED(CONFIG_BPF_JIT_ALWAYS_ON) || >> - bpf_prog_has_kfunc_call(fp)) >> + fp->must_jit) >> jit_needed = true; >> > > Got it. Will follow your suggestion. > > Thanks, > Leon >
