Hello, On Thu, Nov 15, 2018 at 4:50 PM Andrew Jones <drjones@xxxxxxxxxx> wrote: > > On Thu, Nov 15, 2018 at 03:36:44PM +0200, Ahmed Soliman wrote: > > mmap(NULL, 6291456, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, > > -1, 0) = 0x7f46ea2a1000 > > madvise(0x7f46ea2a1000, 6291456, MADV_NOHUGEPAGE) = -1 EINVAL (Invalid argument) > > > > For comprehension, this is done on intel core i7-4500U CPU @ 1.80GHz > > Argh. I see what it is. Your config doesn't have CONFIG_TRANSPARENT_HUGEPAGE=y, > so madvise_behavior_valid() returns false, which causes madvise() to > immediately return EINVAL. We should be more careful in kvm selftests with > our madvise behavior use. > > > > > As for now I will comment the madvise line and the assert when writing > > my own kvm self test. I think it wouldn't cause any trouble?, If it is > > not the case, please let me know. > > > > You may not need madvise() at all for your test, depending on what you're > doing. So leaving it out may be fine. Reworking kvm selftests to ensure > only valid madvise behaviors are used (and only when necessary), before > adding new tests, would be best. Confirmed it worked after CONFIG_TRANSPARENT_HUGEPAGE=y I will send a patch soon that should make the self test check if Transparent huge pages are enabled first before issuing the related madvise() Thanks, -- Ahmed, Junior Researcher, IoT and Cyber Security lab, SmartCI, Alexandria University, & CIS @ VMI
