Writeback drain stalls Tasks-RCU, panics hosts on BPF detach
Cgroup writeback cleanup can run for minutes without a Tasks-RCU quiescent state on lazy-preempt kernels, blocking ftrace and BPF unlinks until the hung-task detector fires.
By kexec#preemption
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 oopsBPF stack helpers race fixed to stop out-of-bounds writes
Preemptible programs could reuse a per-CPU callchain buffer and inflate the copy length past the caller's buffer.
By oopsLinux shortens IPI waits that blocked preemption
Core 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