Long-term support and backport risk [LWN.net]

Long-term support and backport risk

Posted Jun 20, 2007 18:08 UTC (Wed) by pj (subscriber, #4506)
Parent article: Long-term support and backport risk

How about more and better testing? Get vendors to fund hardware virtualization projects for the peripherals they want to be able to keep supporting - that way every developer can have access to 'the hardware', even if it's only virtual hardware. As long as it works the same, it should be fine. This would also allow for more and better automated test suites to be built by people like the autotest project.

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Long-term support and backport risk

Posted Jun 20, 2007 20:10 UTC (Wed) by amikins (subscriber, #451) [Link]

It is very difficult to build a software construct of a piece of hardware that acts sufficiently alike the real hardware enough for driver testing.
This only really works well if the emulated device is created by the same folks what made the physical device.. and even then, there's a substantial probability of deviance in behavior.
In the case of devices where they're having to be reverse engineered just to produce a driver.. TALKING to the device is hard enough, without having to replicate behavior that isn't entirely understood.

Long-term support and backport risk

Posted Jun 23, 2007 2:38 UTC (Sat) by kingdon (subscriber, #4526) [Link]

Well, one side effect of writing such an emulator is that understanding of the hardware improves. Sure, if you are reverse engineering and guessing it becomes harder, but that is true with or without the emulator.

Now, unless there is a fairly big cultural shift, I don't really see these kinds of emulators and autotests getting popular in the kernel world (and I'll fully admit that this kind of thing is easier for, say, compilers than kernels, which have things like locking and races all over the place). But that's more a statement of "I don't think people are going to try it" than "I think if they did try it, it would be useless".