On Tue, 3 Mar 2026 at 17:04, <[email protected]> wrote: > > > diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c > > --- a/kernel/bpf/core.c > > +++ b/kernel/bpf/core.c > > [ ... ] > > > + switch (match) { > > + case BPF_MAP_OWNER_MATCH_FOR_INIT: > > + if (owner->kprobe_write_ctx != aux->kprobe_write_ctx) > > + return false; > > + break; > > + > > + case BPF_MAP_OWNER_MATCH_FOR_UPDATE: > > + if (!owner->kprobe_write_ctx && aux->kprobe_write_ctx) > > + return false; > > + break; > > + } > > In the v1 review, Alexei Starovoitov asked for strict conformance > both ways rather than one-directional validation: > > "Don't be fancy. Require strict conformance both ways > in *all* patches." > > https://lore.kernel.org/bpf/caadnvq+-v0-1i8_+cypk7g0cnv-2n8e9szv43ym3az197el...@mail.gmail.com/ > > The BPF_MAP_OWNER_MATCH_FOR_UPDATE case still uses one-directional > matching, rejecting only !owner->kprobe_write_ctx && aux->kprobe_write_ctx > but allowing the reverse. Was this an intentional design choice, and > if so, should the changelog note the disagreement? >
Let's follow the approach Alexei outlined, while the changes look ok to me, let's remove the one way check and just do owner->kprobe_write_ctx != aux->kprobe_write_ctx, same for the other two checks. With this we can also get rid of this INIT vs UPDATE distinction. Other than that I think patches are good, please also test both directions in the selftest in next respin. > > --- > AI reviewed your patch. Please fix the bug or email reply why it's not a bug. > See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md > > CI run summary: https://github.com/kernel-patches/bpf/actions/runs/22630000544
