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. -- Joe
