Shuah, Do kselftests require to be backward-compatible? I see Documentation/dev-tools/kselftest.rst does not require this, but maybe it's assumed like in other test suites (or in perf). | In general, the rules for selftests are | | * Do as much as you can if you're not root; | | * Don't take too long; | | * Don't break the build on any architecture, and | | * Don't cause the top-level "make run_tests" to fail if your feature is | unconfigured. For example LTP says: | LTP test should be as backward compatible as possible. [...] | | Therefore LTP test for more current features should be able to cope with older | systems. Also, (it's said[1]) perf, even though in kernel tree, is supposed to work properly on any (older/newer) version of Linux. Can you clarify this point in kselftest.rst? I think, this would be useful for future kselftests developers, users, and packagers. (Currently, I package for ALT Linux kselftests (and perf) from the latest mainline branch, so people could test even older kernels with the latest kselftests. If there is policy to be backward-compatible kselftests in the future could reach a state where users would run them in all pass mode (without selecting only working tests). This, in turn, would increase [ease of] usability of tests and thus frequency of their run and consequentially quality kernel testing overall. Thanks, [1] https://lkml.org/lkml/2020/7/29/677
