Based on upstream maintainer's comment about 1 GB not being enough [1] I tested with more RAM (QEMURAM=3600) and it solved the problem [2]. Let's see if Neil's v2 fix [3] is merged in upstream or not. [1] https://lore.kernel.org/linux-nfs/ZiZnbV+htcvGuGQl@tissot.1015granger.net/ [2] http://quasar.suse.cz/tests/3237 [3] https://lore.kernel.org/linux-nfs/171385732687.7600.2864936377155228614@noble.neil.brown.name/