On 12/21/2017 01:00 PM, David Hildenbrand wrote: > On 20.12.2017 13:23, Christian Borntraeger wrote: >> FWIW, this patch set has survived some testing on my side (with storage >> keys, with VSIE, with both), so I would say that after a respin with some >> patch sqashing we give it some more days for the last reviews and then apply >> the whole thing via a topic branch via Martins s390 tree. I will merge >> this branch as well to solve the potential conflicts with >> Davids patch ( s390x/mm: cleanup gmap_pte_op_walk() ) which is still >> pending in my tree >> > > "postcopy works every second try, seems to be QEMU or my setup". > Shouldn't we first understand why? gmap is a very sensible topic and we > should rather spend more time understanding everything. We don't want > guest escalation bugs. I somehow missed that in the cover letter. Yes we should make sure that this works ( on the other hand I usually blame postcopy because userfault makes several assumptions which are somewhat "brave". See the empty zero page issue, which could in theory also break if a postcopy guest does some clever ballooning in and out). But anyway I will have a look after christmas into postcopy. FWIW; Martin and I looked over the patches and they seem good enough (after we fixed postcopy). I also did some testing on that and it seems to work fine so far (including classic migration).
