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I'm not sure I would call the new robust futex destroy hook solution "small". Also, I don't think it would be sufficient to fix the robust PI futex races (my approach handles this as well, see follow up patches). > Your vdso version includes asm code which needs to be implemented by > every architecture. Correct. > The exception table did not look like something that > universally available. Indeed, we'd need to port the vDSO exception table code from x86 to other archs. > Also, if we take this seriously it needs to be > backported to every stable kernel. Yes. The same can be said about the hypothetical robust futex destroy hook. That being said, I do not expect any "easy" fix for a design bug that's been unsolved for 16+ years. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com