On Thu, 7 Nov 2019, Joe Lawrence wrote: > On 11/7/19 9:53 AM, Miroslav Benes wrote: > > On Thu, 7 Nov 2019, Joe Lawrence wrote: > > > >> On 11/7/19 3:42 AM, Miroslav Benes wrote: > >>> On Wed, 6 Nov 2019, Joe Lawrence wrote: > >>> > >>>> The livepatch selftests compare expected dmesg output to verify kernel > >>>> behavior. They currently filter out "tainting kernel with > >>>> TAINT_LIVEPATCH" messages which may be logged when loading livepatch > >>>> modules. > >>>> > >>>> Further filter the log to also drop "loading out-of-tree module taints > >>>> kernel" messages in case the klp_test modules have been build without > >>>> the in-tree module flag. > >>> > >>> That is true, but "tainting kernel with TAINT_LIVEPATCH" should be printed > >>> out even in this case. check_modinfo_livepatch() is called for all modules > >>> and relies on MODINFO(livepatch, Y). > >>> > So either the bug is elsewhere or I need one more cup of tea. > > > > Ok, the above is not relevant here. > > > > I'm only wondering about the execution steps, because supporting modules > > lib/livepatch/ should be built as in-tree. No? > > > > Ah, I see. Well as you noted they are modprobed, so theoretically they could > come from anywhere OOT, right? Yes. > In my test, I had a kernel tree, but only wanted to build the test modules. > Once I did a 'make modules SUBDIR=' or 'make M= ...' KBUILD_EXTMOD got flipped > on and the modules lost in-tree status. No amount of googling could tell me > how to build a single in-tree directory of modules :( "make lib/livepatch/test_klp_livepatch.ko" should do the trick. "make lib/livepatch/" only builds the object files and I haven't found a way to make it link .ko modules other than specifying them one by one directly. > And then it seemed that > opening the tests for OOT modules was reasonable anyway. That's an interesting idea. If a module is in tree, it is under our control. So we know what "testing capabilities" it offers. I guess that with OOT testing modules the selftests would have to be smarter. Miroslav
