On Fri, 17 Apr 2026, Joe Lawrence wrote: > On Thu, Apr 16, 2026 at 03:18:33PM -0300, Marcos Paulo de Souza wrote: > > On Thu, 2026-04-16 at 10:07 -0700, Josh Poimboeuf wrote: > > > On Mon, Apr 13, 2026 at 02:26:11PM -0300, Marcos Paulo de Souza > > > wrote: > > > > A new version of the patchset, with fewer patches now. Please take > > > > a look! > > > > > > > > Original cover-letter: > > > > These patches don't really change how the patches are run, just > > > > skip > > > > some tests on kernels that don't support a feature (like kprobe and > > > > livepatched living together) or when a livepatch sysfs attribute is > > > > missing. > > > > > > > > The last patch slightly adjusts check_result function to skip dmesg > > > > messages on SLE kernels when a livepatch is removed. > > > > > > Why are we adding complexity to support Linux 4.12 in mainline? > > > Isn't > > > that what enterprise distros are for? > > > > These changes do not add any new complex code, just checks to enable > > the tests to run on older kernels. I believe that it would be good for > > all enterprises distros if they could run more tests in maintenance > > updates of their kernels using the upstream tests. > > > > The changes are not really that big. Some patches were removed from v1 > > because there were adding checks for out-of-tree messages (like the > > last paragraph of the v2 erroneously shows), and another one was to > > check if kprobes could live alongside livepatches, which fails for 4.12 > > kernels. > > > > The patches for this versions introduce only checks to avoid testing > > sysfs attributes for kernels that don't supports them. > > > > IMHO when the changes are reasonably small, I think we should consider > accomodating older kernels for the selftest suite. If we reach the > point of having to introduce version #ifdef-erry, that opinion would > flip pretty quickly. It's pretty amazing that modern tests still run on > older kernels (with this patchset) -- not an explicit kselftest goal > AFAIK, but nice to have. > > If we do merge this patchset, it should update the doc > tools/testing/selftests/livepatch/README to note the oldest > expected/tested upstream kernel. (So new selftest authors may have some > idea of what API / sysfs features to use.) And that this compatibility > was only an incidental "feature" that came for nearly free. It's not a > promise to never add backwards-incompatible tests in the future.
I agree with Joe on both points. Miroslav
