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Do they not have a source repository with commit history and code reviews with names attached? Is that something unreasonable to expect from a multi-billion dol
by deegles 11y ago
Do they not have a source repository with commit history and code reviews with names attached? Is that something unreasonable to expect from a multi-billion dollar company?
- dboreham 11y agoThe code was supposedly written by a vendor or subcontractor, so it could have been delivered in a "drop" to VW without commit history. Also, the story seems to have been that the "cheat" was a special mode explicitly programmed for test purposes and not something totally under the covers. The "crime" was in enabling that mode under field conditions. That change may not be covered by source code revision control, if it were made in a config file outside of SCC. In a field more of us here understand, it would be similar to coding a feature in a server that dumps user passwords to the log file in plain text. Such a feature would be useful for certain debugging situations, but it would be disastrous to have it enabled on a production box. So you'd put a big all-caps warning in the source code, documentation, example config files saying whatever you do don't turn this on in production. Supposedly the engine management developers did something along those lines, but the folks who built the cars ignored the warning and enabled the mode anyway.
- kbenson 11y agoThat may be, but it ignores the fact that software was written for the express purpose of not just identifying if a test was being ran, but then taking action to change the results of the test has no real world use. Any case where you would want to change engine performance has no reason to be triggered only when testing. To get both included in production as-is and turned on requires quite a series of consecutive mistakes to be considered accidental. > In a field more of us here understand, it would be similar to coding a feature in a server that dumps user passwords to the log file in plain text. No, it's like coding that feature but explicitly making it turn off whenever it detects a security review. How is that justifiable?
- dboreham 11y agoYeah, I like your continuation of my analogy. However, as I understand it, from someone I know who worked in the automotive sector a while back, all vehicles have a special emissions test mode. It exists for legitimate reasons such as you don't want to have ABS turned on when on a dyno for safety reasons. It probably also exists for less legitimate reasons arising out of the history of testing practice -- essentially that the test never has been truly representative of real road conditions, and everyone involved in the testing process knew this. That being the case, all you need then is to add one more flag to the list of "things to enable/disable under test conditions". I agree that somewhere there must be some kind of record of when and who made that configuration change though.
- kbenson 11y agoOkay, I can accept there may be a legitimate reason to want to determine if a test is being run for a case like that, but that's a component that isn't related to engine performance and emissions. I'm not sure there's any case where you could legitimately want the engine performance and emissions to be different during emissions testing. In any case you want it different (for example, testing different parameters), you would also want to test it on the road.
- oxryly1 11y agoThese details of emissions modes and engine control software configuration could easily explain the defeat. What remains is explaining how engineering managers higher up (all the way to the top) could remain willfully ignorant of the fact that VW's diesel engines "passed" emissions without resorting to exotic tech like Mercedes' bluetec exhaust fluids. They knew there was some sort of magic in their engines that set them apart, but they either understood it was cheating, or they never asked any questions.
- dboreham 11y agoI suspect this will turn out to be due to some corporate mass psychosis similar to when an airliner suffers controlled flight into terrain because nobody wanted to disagree with the captain.
- superuser2 11y agoInteresting. If this is the story, then VW didn't really "need" to cheat to make the cars reasonable, so they shouldn't get too much worse when patched. That would be a nice outcome. I'm still cynical.
- andreasvc 11y agoI don't understand how that follows. From all I've heard, people suspect that the difference between cheating and test mode is large.
- jacquesm 11y ago> Such a feature would be useful for certain debugging situations, but it would be disastrous to have it enabled on a production box. I've seen that exact thing (and worse...) on a production server in some job recently. But that big all-caps warning wasn't there, the docs were absent and there was no config bit to switch on/off, I found the file more or less by accident (wondering what all the io was that ate up the machine).
- toephu2 11y agoVW != Silicon Valley startup.
- dexterdog 11y agoHe did say code reviews
- ThrustVectoring 11y agoThis is exactly the use case for signed commits and pushes.
- branchless 11y agoAgreed, but this has to be more than just software. The engineers must have some idea of emissions then suddenly it's not a problem any more? And they just think "that's lucky".