On Mon, Sep 21, 2026 at 12:32 AM Weiming Shi <[email protected]> wrote:
> Cc: [email protected]
> Fixes: be8704ff07d2 ("bpf: Introduce dynamic program extensions")
That shouldn't go to stable. Loading an EXT prog takes CAP_BPF +
CAP_NET_ADMIN + CAP_PERFMON.
[...]
> + if (prog->type == BPF_PROG_TYPE_EXT && READ_ONCE(prog->cb_access)) {
> + WRITE_ONCE(tgt_prog->cb_access, true);
> + /* Drain runs that observed cb_access=false before enabling
> freplace. */
> + synchronize_rcu();
> + }
tc doesn't look at cb_access at all, yet every tc freplace that touches
cb[] now waits for an RCU grace period in attach.
This is a separate issue from the LWT one. Patch 2 resets the cb after
the run whether the prog has cb_access or not, so it doesn't depend on
this patch. Pls drop it from this series.
