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BPF is compatible with DTrace probes. The kernel verifier does extensive bounds checks on array uses and jumps in BPF programs.

• rurban 8y ago
  Those checks don't save you from spectre-like cache exploitation. DTrace was designed with maps-only for a reason. Thanksfully there's now Oracle Linux with DTrace-proper. When the usdt syntax can use static DTrace probes, why isn't it documented then? and why doesn't it use the familiar DTrace syntax then? Why is nobody using it?
  • dan-robertson 8y ago
    > DTrace was designed with maps-only for a reason. You write this like you are implying that the DTrace designers somehow foresaw that spectre would be a thing and therefore array accesses would be a risk. This is obviously false. I’m sure there are reasonable reasons to not have arrays but predicting spectre 10 years before it was found is not one of them.
    • rurban 8y ago
      Ask Brian, he did it on purpose.