Short: I can't reproduce here with L1 guest having has host-passthrough for CPU.
Long: ===== Version Info: ------------- On Physical host: ~~~~~~~~~~~~~~~~~ $ uname -r; rpm -q libvirt-daemon-kvm qemu 3.10.0-0.rc2.git1.2.fc20.x86_64 qemu-1.4.2-3.fc19.x86_64 libvirt-daemon-kvm-1.0.5.2-1.fc19.x86_64 libguestfs-1.22.3-1.fc19.x86_64 On L1: ~~~~~~ $ uname -r; rpm -q libvirt-daemon-kvm qemu 3.10.0-0.rc3.git0.2.fc20.x86_64 libvirt-daemon-kvm-1.0.5.1-1.fc19.x86_64 qemu-1.4.2-2.fc19.x86_64 [root@dhcp47-209 ~]# L1 guest CLI: ------------- [root@bare-metal ~]# ps -ef | grep qemu qemu 7281 1 67 04:57 ? 00:00:10 /usr/bin/qemu-system-x86_64 -machine accel=kvm -name regular-guest -S -machine pc-i440fx-1.4,accel=kvm,usb=off -cpu host -m 10240 -smp 4,sockets=4,cores=1,threads=1 -uuid 4ed9ac0b-7f72-dfcf-68b3-e6fe2ac588b2 -nographic -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/regular-guest.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/home/test/vmimages/regular-guest.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev tap,fd=23,id=hostnet0,vhost=on,vhostfd=24 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:80:c1:34,bus=pci.0,addr=0x3 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -device usb-tablet,id=input0 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 L2 guest CLI: ------------- [root@regular-guest ~]# ps -ef | grep -i qemu qemu 1138 1 88 05:18 ? 00:00:07 /usr/bin/qemu-system-x86_64 -machine accel=kvm -name nguest-01 -S -machine pc-i440fx-1.4,accel=kvm,usb=off -m 2048 -smp 2,sockets=2,cores=1,threads=1 -uuid b47c5cbb-b320-ce9d-c595-4e083b0e465d -nographic -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/nguest-01.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/home/test/vmimages/nguest-01.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev tap,fd=23,id=hostnet0,vhost=on,vhostfd=24 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:be:d5:8e,bus=pci.0,addr=0x3 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -device usb-tablet,id=input0 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 A search for string 'error' in logs doesn't turn up anything: [root@nguest-01 ~]# grep -i error /var/log/boot.log [root@nguest-01 ~]# grep -i error /var/log/messages [root@nguest-01 ~]# Yongjie, can you please re-try? -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/994378 Title: Nested-virt)L1 (kvm on kvm)guest panic with parameter “-cpu host” in qemu command line. Status in QEMU: New Bug description: Environment: ------------ Host OS (ia32/ia32e/IA64):ia32e Guest OS (ia32/ia32e/IA64):ia32e Guest OS Type (Linux/Windows):Linux kvm.git Commit:19853301ef3289bda2d5264c1093e74efddaeab9 qemu-kvm Commit:69abebf20280152da8fa7c418a819ae51e862231 Host Kernel Version:3.4.0-rc3 Hardware:WSM-EP, Romley-EP Bug detailed description: -------------------------- (KVM on KVM) L1 guest panic when starting the L1 guest with “-cpu host” parameter in qemu command line. Note: 1. when creating guest with “-cpu qemu64,+vmx”, L1 guest and L2 guest can boot up. 2. This should be a qemu-kvm bug. using '-cpu host' parameter, the following is the result. Kvm + qemu-kvm =result 19853301 + 69abebf2 = bad 19853301 + 44755ea3 = good 3. when booting up the guest with the good commit of 19853301 + 44755ea3, you can see some error info, but nested virt works fine. (L1 and L2 guest can boot up.) “error: feature "i64" not available in set error: bad option value [extfeature_edx = i64 xd syscall]” some logs [root@vt-snb9 x86_64-softmmu]# ./qemu-system-x86_64 -m 2048 -net nic,model=rtl8139 -net tap,script=/etc/kvm/qemu-ifup -hda /root/nested-kvm.qcow -cpu host error: feature "i64" not available in set error: bad option value [extfeature_edx = i64 xd syscall] error: feature "i64" not available in set error: bad option value [extfeature_edx = i64 xd syscall] error: feature "i64" not available in set error: bad option value [extfeature_edx = i64 syscall xd] error: feature "i64" not available in set error: bad option value [extfeature_edx = i64 syscall xd] VNC server running on `::1:5900' Reproduce steps: ---------------- 1.start up a host with kvm (commit: 19853301) 2.rmmod kvm_intel 3.modprobe kvm_intel nested=1 4.qemu-system-x86_64 -m 2048 -hda L1-kvm.img -cpu host Current result: ---------------- L1 guest panic. Expected result: ---------------- L1 guest and L2 guest boot up correctly. Basic root-causing log: ---------------------- To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/994378/+subscriptions
