Hello, I did quick test with latest stable kernel (4.16.2) and got tons of vmwrite errors immediately when starting VM: Apr 17 08:22:05 192.168.1.4 merkur kernel: vmwrite error: reg 401e value 2021 (err 12) Apr 17 08:22:05 192.168.1.4 merkur kernel: CPU: 0 PID: 1876 Comm: qemu-test4 Not tainted 4.16.2-1-core2 #1 Apr 17 08:22:05 192.168.1.4 merkur kernel: Hardware name: /DG35EC, BIOS ECG3510M.86A.0118.2010.0113.1426 01/13/2010 Apr 17 08:22:05 192.168.1.4 merkur kernel: Call Trace: Apr 17 08:22:05 192.168.1.4 merkur kernel: dump_stack+0x5c/0x82 Apr 17 08:22:05 192.168.1.4 merkur kernel: vmx_set_cr4+0x1ca/0x200 [kvm_intel] Apr 17 08:22:05 192.168.1.4 merkur kernel: vmx_vcpu_reset+0x320/0x660 [kvm_intel] Apr 17 08:22:05 192.168.1.4 merkur kernel: kvm_vcpu_reset+0x1f6/0x300 [kvm] Apr 17 08:22:05 192.168.1.4 merkur kernel: ? vcpu_load+0x1f/0x30 [kvm] Apr 17 08:22:05 192.168.1.4 merkur kernel: kvm_arch_vcpu_setup+0x1b/0x30 [kvm] Apr 17 08:22:05 192.168.1.4 merkur kernel: kvm_vm_ioctl+0x1ea/0x750 [kvm] Apr 17 08:22:05 192.168.1.4 merkur kernel: do_vfs_ioctl+0x8b/0x5e0 Apr 17 08:22:05 192.168.1.4 merkur kernel: SyS_ioctl+0x36/0x70 Apr 17 08:22:05 192.168.1.4 merkur kernel: do_syscall_64+0x6a/0x2f0 Apr 17 08:22:05 192.168.1.4 merkur kernel: ? __switch_to+0x11b/0x340 Apr 17 08:22:05 192.168.1.4 merkur kernel: entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Apr 17 08:22:05 192.168.1.4 merkur kernel: RIP: 0033:0x7f56ccd0fb77 Apr 17 08:22:05 192.168.1.4 merkur kernel: RSP: 002b:00007f56c8df4988 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 Apr 17 08:22:05 192.168.1.4 merkur kernel: RAX: ffffffffffffffda RBX: 000000000000ae41 RCX: 00007f56ccd0fb77 Apr 17 08:22:05 192.168.1.4 merkur kernel: RDX: 0000000000000001 RSI: 000000000000ae41 RDI: 000000000000000e Apr 17 08:22:05 192.168.1.4 merkur kernel: RBP: 0000000000000001 R08: 0000556e8e5ed600 R09: 0000556e907fa5f0 Apr 17 08:22:05 192.168.1.4 merkur kernel: R10: 0000556e8ebc7620 R11: 0000000000000246 R12: 0000556e9076f540 Apr 17 08:22:05 192.168.1.4 merkur kernel: R13: 00007f56c8df59c0 R14: 0000000000000000 R15: 0000000000000003 model name : Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm pti tpr_shadow dtherm 4.15.17 works fine, it seems already reported here: https://bugzilla.redhat.com/show_bug.cgi?id=1566258 Z.
