Description of problem: kvm program exited auto after hotplug 16 vcpus Version-Release number of selected component (if applicable): kvm-83-127.el5 How reproducible: always Steps to Reproduce: 1. start vm with smp=1 CLI: #/usr/libexec/qemu-kvm -drive file=~/share/images/Fedora-11-32.qcow2,if=ide -no-hpet -rtc-td-hack -smp 1 -m 2G -uuid `uuidgen` -net nic,model=virtio,macaddr=00:A6:08:FA:DD:55,vlan=0 -net tap,vlan=0,script=/etc/qemu-ifup -cpu qemu64,+sse2 -boot c -vnc :6 -name F10-32 -monitor stdio 2. (qemu) cpu_set 1 online (repeat add cpu to 16) 3. Actual results: after cpu_set 16 online, program exited automatically. Expected results: Additional info: 1. error: kvm_create_vcpu: Invalid argument kvm_set_lapic: Bad file descriptor kvm_setup_cpuid2: Bad file descriptor KVM_TPR_ACCESS_REPORTING: Bad file descriptor kvm_set_msrs FAILED: Bad file descriptor kvm_run: Bad file descriptor kvm_run returned -9 2. (gdb)bt No stack. 3. host: processor : 1 vendor_id : AuthenticAMD cpu family : 15 model : 67 model name : Dual-Core AMD Opteron(tm) Processor 1216 stepping : 3 4. guest: Fedora11-32, RHEL5.4-server-32 5. dmesg: connection1:0: detected conn error (1011) connection2:0: detected conn error (1011) connection1:0: detected conn error (1011) connection2:0: detected conn error (1011) connection1:0: detected conn error (1011) connection2:0: detected conn error (1011) connection2:0: detected conn error (1011) connection1:0: detected conn error (1011) connection2:0: detected conn error (1011) connection1:0: detected conn error (1011) breth0: port 2(tap0) entering disabled state device tap0 left promiscuous mode breth0: port 2(tap0) entering disabled state
RHEL5 KVM only supports up to 16 vcpus. Trying to add more vcpus than supported by KVM will make qemu abort because it can't handle the semi-initialized state after vcpu_create() fails. See bug 587661 for a related patch that changed qemu to explicitly abort when vcpu_create() fails.