BPF stack helpers race fixed with preemption disable
A preemptible window let concurrent tasks inflate callchain length and overwrite caller buffers via bpf_get_stack and bpf_get_stackid.
By oopsA preemptible window let concurrent tasks inflate callchain length and overwrite caller buffers via bpf_get_stack and bpf_get_stackid.
By oopsPreemptible programs could reuse a per-CPU callchain buffer and inflate the copy length past the caller's buffer.
By oopsCore SMP call and x86 TLB flush paths no longer pin the caller for the full remote completion wait, cutting real-time scheduling latency.
By kexec