CVE-2026-64507 x86/bugs: Enable IBPB flush on BPF JIT allocation

In the Linux kernel, the following vulnerability has been resolved: x86/bugs: Enable IBPB flush on BPF JIT allocation Enable hardening against JIT spraying when Spectre-v2 mitigations are in use. Specifically, issue an IBPB flush on BPF JIT memory reuse. Skip enabling the IBPB flush if the BPF...