Topical Takes

Short, opinionated posts on eBPF, Linux internals, and the tools we all run in production.

AlleBPF20linux19yeet16observability11networking4uprobes4AI agents3kubernetes3security3tcpdump3BSON2containers2HTTP2MongoDB2process-attribution2tracing2802.111ai-sre1audit1bcc1biolatency1bpf-verifier1bpftrace1cgroups1Cilium1claude-code1CO-RE1context-switches1cpu-accounting1cryptojacking1incident-response1integration-testing1kprobes1kworker1memory1n-plus-one1off-cpu1oom1opentelemetry1packet-capture1prepared statements1proc-filesystem1process-masquerading1profiling1query-shapes1Redis1RESP1rf1root-cause-analysis1runqlat1schedstat1slowlog1SQLite1stratum1tcp-retransmits1tunnels1websocket1wifi1wireguard1wireless1wss1

Writing an eBPF Protocol Tracer on Linux in 2026: Why the Verifier Wants Your Parser in Userspace

The verifier rejects a parsing loop because it cannot bound a trip count read from user memory, and that is design feedback rather than an obstacle. Compares bpftrace, BCC, libbpf and yeet, then covers back-edge errors, the 512-byte stack limit, per-CPU scratch maps, request/reply correlation and CO-RE field renames across kernels.

eBPFbpf-verifierCO-REkprobesBSONlinuxtracingyeet
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