Hi, I'm seeing a breakage on q35 migration on head (and possibly older but certainly head; it's also on a 2.5.0 world I've got with a bunch of patches but I've not tried a clean 2.5.0 yet).
It looks like some type of interrupt screwup; with a virtio-net device I get a: BUG: soft lockup - CPU#0 stuck for 22s! ... virtnet_config_changed_work but if I swap that out for an e1000 I get: Disabling IRQ #22 and various timeouts on e1000 and cdrom (scsi). The guest kind of limps along with an existing terminal scrolling dmesg -w output. This is an f23 guest on a rhel7.2-ish host; with the guest sitting an idle (MATE) Gui. i440fx works. qemu 30823 1 15 14:51 ? 00:00:07 /opt/qemu-head/bin/qemu-system-x86_64 -name f23-q35 -S -machine pc-q35-2.6,accel=kvm,usb=off,vmport=off -cpu SandyBridge -m 4096 -realtime mlock=off -smp 4,sockets=4,cores=1,threads=1 -uuid 3cc93d9b-9b87-4472-847c-25cea2bfc51f -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-12-f23-q35/monitor.sock,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -global ICH9-LPC.disable_s3=1 -global ICH9-LPC.disable_s4=1 -boot strict=on -device i82801b11-bridge,id=pci.1,bus=pcie.0,addr=0x1e -device pci-bridge,chassis_nr=2,id=pci.2,bus=pci.1,addr=0x1 -device ich9-usb-ehci1,id=usb,bus=pcie.0,addr=0x1d.0x7 -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pcie.0,multifunction=on,addr=0x1d -device ich9-usb-uhci2,masterbus=usb.0,firstport=2,bus=pcie.0,addr=0x1d.0x1 -device ich9-usb-uhci3,masterbus=usb.0,firstport=4,bus=pcie.0,addr=0x1d.0x2 -device virtio-scsi-pci,id=scsi0,bus=pci.2,addr=0x3 -device virtio-serial-pci,id=virtio-serial0,bus=pci.2,addr=0x4 -drive file=/home/vms/f23-q35.qcow2,format=qcow2,if=none,id=drive-virtio-disk0,cache=none -device virtio-blk-pci,scsi=off,bus=pci.2,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -drive if=none,id=drive-scsi0-0-0-0,readonly=on -device scsi-cd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0 -netdev tap,fd=25,id=hostnet0 -device e1000,netdev=hostnet0,id=net0,mac=52:54:00:98:12:7d,bus=pci.2,addr=0x1 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -chardev socket,id=charchannel0,path=/var/lib/libvirt/qemu/channel/target/domain-12-f23-q35/org.qemu.guest_agent.0,server,nowait -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=org.qemu.guest_agent.0 -chardev spicevmc,id=charchannel1,name=vdagent -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=com.redhat.spice.0 -device usb-tablet,id=input0 -spice port=5900,addr=127.0.0.1,disable-ticketing,seamless-migration=on -device qxl-vga,id=video0,ram_size=67108864,vram_size=67108864,vram64_size_mb=0,vgamem_mb=16,bus=pcie.0,addr=0x1 -device intel-hda,id=sound0,bus=pci.2,addr=0x2 -device hda-duplex,id=sound0-codec0,bus=sound0.0,cad=0 -chardev spicevmc,id=charredir0,name=usbredir -device usb-redir,chardev=charredir0,id=redir0 -chardev spicevmc,id=charredir1,name=usbredir -device usb-redir,chardev=charredir1,id=redir1 -incoming defer -device virtio-balloon-pci,id=balloon0,bus=pci.2,addr=0x6 -msg timestamp=on (Attaching libvirt xml that generated that lot). Dave -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
<!-- WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE OVERWRITTEN AND LOST. Changes to this xml configuration should be made using: virsh edit f23-q35 or other application using the libvirt API. --> <domain type='kvm'> <name>f23-q35</name> <uuid>3cc93d9b-9b87-4472-847c-25cea2bfc51f</uuid> <memory unit='KiB'>4194304</memory> <currentMemory unit='KiB'>4194304</currentMemory> <vcpu placement='static'>4</vcpu> <os> <type arch='x86_64' machine='pc-q35-2.6'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <vmport state='off'/> </features> <cpu mode='custom' match='exact'> <model fallback='allow'>SandyBridge</model> </cpu> <clock offset='utc'> <timer name='rtc' tickpolicy='catchup'/> <timer name='pit' tickpolicy='delay'/> <timer name='hpet' present='no'/> </clock> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <pm> <suspend-to-mem enabled='no'/> <suspend-to-disk enabled='no'/> </pm> <devices> <emulator>/opt/qemu-head/bin/qemu-system-x86_64</emulator> <disk type='file' device='disk'> <driver name='qemu' type='qcow2' cache='none'/> <source file='/home/vms/f23-q35.qcow2'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x02' slot='0x05' function='0x0'/> </disk> <disk type='file' device='cdrom'> <driver name='qemu' type='raw'/> <target dev='sda' bus='scsi'/> <readonly/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> <controller type='usb' index='0' model='ich9-ehci1'> <address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x7'/> </controller> <controller type='usb' index='0' model='ich9-uhci1'> <master startport='0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x0' multifunction='on'/> </controller> <controller type='usb' index='0' model='ich9-uhci2'> <master startport='2'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x1'/> </controller> <controller type='usb' index='0' model='ich9-uhci3'> <master startport='4'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x2'/> </controller> <controller type='sata' index='0'> <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/> </controller> <controller type='pci' index='0' model='pcie-root'/> <controller type='pci' index='1' model='dmi-to-pci-bridge'> <model name='i82801b11-bridge'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/> </controller> <controller type='pci' index='2' model='pci-bridge'> <model name='pci-bridge'/> <target chassisNr='2'/> <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/> </controller> <controller type='scsi' index='0' model='virtio-scsi'> <address type='pci' domain='0x0000' bus='0x02' slot='0x03' function='0x0'/> </controller> <controller type='virtio-serial' index='0'> <address type='pci' domain='0x0000' bus='0x02' slot='0x04' function='0x0'/> </controller> <interface type='network'> <mac address='52:54:00:98:12:7d'/> <source network='default'/> <model type='e1000'/> <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/> </interface> <serial type='pty'> <target port='0'/> </serial> <console type='pty'> <target type='serial' port='0'/> </console> <channel type='unix'> <source mode='bind'/> <target type='virtio' name='org.qemu.guest_agent.0'/> <address type='virtio-serial' controller='0' bus='0' port='1'/> </channel> <channel type='spicevmc'> <target type='virtio' name='com.redhat.spice.0'/> <address type='virtio-serial' controller='0' bus='0' port='2'/> </channel> <input type='tablet' bus='usb'/> <input type='mouse' bus='ps2'/> <input type='keyboard' bus='ps2'/> <graphics type='spice' autoport='yes'/> <sound model='ich6'> <address type='pci' domain='0x0000' bus='0x02' slot='0x02' function='0x0'/> </sound> <video> <model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/> </video> <redirdev bus='usb' type='spicevmc'> </redirdev> <redirdev bus='usb' type='spicevmc'> </redirdev> <memballoon model='virtio'> <address type='pci' domain='0x0000' bus='0x02' slot='0x06' function='0x0'/> </memballoon> </devices> </domain>