Hello Christian, Attached you can find a xenial SRU patch based on commit (https://github.com/libvirt/libvirt/commit/7e667664d28f90bf6916604a55ebad7e2d85305b).
Here is the guest definition used on my testing (http://paste.ubuntu.com/25288141/) Without the patch, the error is reproduced. root@buneary:/home/ubuntu# virsh start reproducer2 error: Failed to start domain reproducer2 error: internal error: process exited while connecting to monitor: mlockall: Cannot allocate memory 2017-08-11T03:59:54.936275Z qemu-system-x86_64: locking memory failed With the patch the guest is initialized correctly. root@buneary:/var/lib/uvtool/libvirt/images# virsh start reproducer2 Domain reproducer2 started I ran the following systemtap probe (probe kernel.function("sys_setrlimit") { printf("locked: %d -> %s\n", pid(), sprintf("%s, %s", _rlimit_resource_str($resource), _struct_rlimit_u($rlim))) } ) And the output shows that the RLIMIT_MEMLOCK process limit is set to 9007199254740991 (VIR_DOMAIN_MEMORY_PARAM_UNLIMITED) root@buneary:/home/ubuntu# stap -g qemu_probe.stap -kv -g --suppress-time-limits Pass 1: parsed user script and 465 library scripts using 112796virt/48440res/6664shr/42136data kb, in 130usr/40sys/164real ms. Pass 2: analyzed script: 1 probe, 5 functions, 100 embeds, 0 globals using 164772virt/101848res/7988shr/94112data kb, in 660usr/120sys/776real ms. Pass 3: translated to C into "/tmp/stapVXuoMi/stap_30601_src.c" using 164772virt/102040res/8180shr/94112data kb, in 10usr/0sys/5real ms. Pass 4: compiled C into "stap_30601.ko" in 2160usr/540sys/3231real ms. Pass 5: starting run. locked: 31028 -> RLIMIT_MEMLOCK, [9007199254740991,9007199254740991] ** Changed in: libvirt (Ubuntu Artful) Status: Confirmed => Fix Released ** Changed in: libvirt (Ubuntu Artful) Status: Fix Released => Fix Committed ** Patch added: "fix-1708305-xenial.debdiff" https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1708305/+attachment/4930463/+files/fix-1708305-xenial.debdiff -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1708305 Title: Realtime feature mlockall: Cannot allocate memory To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1708305/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs