On my AMD laptop (x130e thinkpad) with a uptodate trusty amd64 install, I cannot reproduce this. After installing a 32-bit trusty image, I can in fact reproduce it: Jan 27 13:07:05 serge-ThinkPad-X130e kernel: [ 725.593411] kvm: zapping shadow pages for mmio generation wraparound Jan 27 13:07:19 serge-ThinkPad-X130e kernel: [ 740.100465] kvm [3887]: vcpu0 unhandled rdmsr: 0xc0010001 Jan 27 13:07:21 serge-ThinkPad-X130e kernel: [ 742.187275] usb 1-1: USB disconnect, device number 3 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524715] BUG: soft lockup - CPU#0 stuck for 22s! [qemu-system-i38:3889] Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524729] Modules linked in: usb_storage parport_pc ppdev joydev rfcomm bnep arc4 uvcvideo rtl8192ce videobuf2_vmalloc videobuf2_memops videobuf2_core videodev rtl_pci kvm_amd rtlwifi kvm rtl8192c_common mac80211 microcode snd_hda_codec_conexant btusb snd_hda_codec_hdmi radeon cfg80211 bluetooth thinkpad_acpi snd_hda_intel snd_hda_codec nvram snd_hwdep snd_seq_midi snd_pcm snd_seq_midi_event snd_rawmidi snd_seq ttm psmouse drm_kms_helper snd_seq_device sp5100_tco snd_page_alloc rtsx_pci_ms serio_raw memstick drm snd_timer i2c_piix4 k10temp wmi i2c_algo_bit snd soundcore video mac_hid lp parport rtsx_pci_sdmmc rtsx_pci atl1c ahci libahci Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524815] CPU: 0 PID: 3889 Comm: qemu-system-i38 Not tainted 3.13.0-5-generic #20-Ubuntu Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524820] Hardware name: LENOVO 062223U/062223U, BIOS 8RET52WW (1.15 ) 11/15/2011 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524825] task: edc78d00 ti: f63e6000 task.ti: f63e6000 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524830] EIP: 0060:[] EFLAGS: 00000202 CPU: 0 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524840] EIP is at __srcu_read_lock+0x2c/0x50 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524845] EAX: f14e4024 EBX: 00000000 ECX: f7bdddf0 EDX: 00000000 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524848] ESI: 00000001 EDI: 00000001 EBP: f63e7dec ESP: f63e7de4 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524852] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524856] CR0: 8005003b CR2: ffffffff CR3: 35e58000 CR4: 000007f0 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524860] Stack: Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524863] f626b550 00000000 f63e7e6c f91da2f6 000000b2 f7bd3400 57c83df4 134d36c2 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524873] f7bd3140 edc78d00 00000046 00000000 edc78d00 f626b550 003e7e24 c1058fb7 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524882] f63e7e30 c164c598 f626b570 f63e7e94 c1644fac f626b570 360df2c8 f14e2008 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524892] Call Trace: Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524933] [] vcpu_enter_guest+0x636/0xc90 [kvm] Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524941] [] ? irq_exit+0x47/0xa0 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524950] [] ? smp_apic_timer_interrupt+0x38/0x50 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524957] [] ? apic_timer_interrupt+0x34/0x3c Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.524988] [] kvm_arch_vcpu_ioctl_run+0x1cf/0x3e0 [kvm] Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525011] [] kvm_vcpu_ioctl+0x433/0x4d0 [kvm] Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525019] [] ? lapic_next_event+0x1b/0x20 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525025] [] ? clockevents_program_event+0x95/0x130 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525031] [] ? tick_program_event+0x29/0x30 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525036] [] ? hrtimer_interrupt+0x142/0x2b0 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525042] [] ? lapic_next_event+0x1b/0x20 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525064] [] ? vcpu_put+0x30/0x30 [kvm] Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525071] [] do_vfs_ioctl+0x2e2/0x4d0 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525078] [] ? ktime_get_ts+0x48/0x140 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525083] [] SyS_ioctl+0x60/0x80 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525088] [] sysenter_do_call+0x12/0x28 Jan 27 13:07:48 serge-ThinkPad-X130e kernel: [ 768.525091] Code: 89 e5 56 53 3e 8d 74 26 00 8b 10 83 e2 01 8b 48 04 64 03 0d 04 d1 a6 c1 8d 1c 95 00 00 00 00 01 d9 8b 31 83 c6 01 89 31 0f ae f0 <89> f6 8b 40 04 64 03 05 04 d1 a6 c1 01 d8 8b 48 08 83 c1 01 89