eBPF spinlock debugging is exactly the kind of kernel work that's simultaneously terrifying and fascinating. Spinlocks in eBPF programs are particularly tricky because you're operating in a context where you can't sleep, can't take mutexes, and the verifier needs to statically prove your lock usage is correct before the program even runs.

The verification challenge is the interesting part. The kernel verifier has to ensure that every path through the eBPF program properly acquires and releases locks, which is essentially solving a subset of the halting problem through conservative static analysis. False positives (rejecting valid programs) are acceptable; false negatives (allowing deadlocks) are not.