heterogeneous cpus are not supported and hotplugging different cpu model crashes QEMU:
qemu-system-x86_64 -cpu qemu64 -smp 1,maxcpus=2 (qemu) device_add host-x86_64-cpu,socket-id=1,core-id=0,thread-id=0,id=foo (qemu) info cpus error: failed to get MSR 0x38d qemu-system-x86_64: target/i386/kvm.c:2121: kvm_get_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed. Aborted (core dumped) Gracefully fail hotplug process in case of user mistake. Reported-by: Greg Kurz <gr...@kaod.org> Signed-off-by: Igor Mammedov <imamm...@redhat.com> --- v2: fix checkpatch error --- hw/i386/pc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 05985d4..8e307f7 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -1876,8 +1876,15 @@ static void pc_cpu_pre_plug(HotplugHandler *hotplug_dev, CPUArchId *cpu_slot; X86CPUTopoInfo topo; X86CPU *cpu = X86_CPU(dev); + MachineState *ms = MACHINE(hotplug_dev); PCMachineState *pcms = PC_MACHINE(hotplug_dev); + if (!object_dynamic_cast(OBJECT(cpu), ms->cpu_type)) { + error_setg(errp, "Invalid CPU type, expected cpu type: '%s'", + ms->cpu_type); + return; + } + /* if APIC ID is not set, set it based on socket/core/thread properties */ if (cpu->apic_id == UNASSIGNED_APIC_ID) { int max_socket = (max_cpus - 1) / smp_threads / smp_cores; -- 2.7.4