path: root/results/classifier/gemma3:12b/hypervisor/1902365

3x 100% host CPU core usage while virtual machine is in idle

My Fedora 33 machine "top" command shows qemu-system-x86_64 process using ~300% CPU, that means 3x CPU cores at 100%. Since the virtual machine (named CentOS 8) is almost in idle (top command inside the VM shows ~0% CPU usage), there must be something wrong. I attach qemu process GDB backtrace, and virtual machine libvirt XML

Host details:
libvirt-6.6.0-2.fc33.x86_64
qemu-system-x86-5.1.0-5.fc33.x86_64
virt-manager-3.1.0-1.fc33.noarch
kernel 5.8.16-300.fc33.x86_64
CPU: AMD Ryzen 5 3600

# gdb qemu-system-x86_64 405756
GNU gdb (GDB) Fedora 9.2-7.fc33
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Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
Type "show configuration" for configuration details.
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Reading symbols from qemu-system-x86_64...
Reading symbols from .gnu_debugdata for /usr/bin/qemu-system-x86_64...
(No debugging symbols found in .gnu_debugdata for /usr/bin/qemu-system-x86_64)
Attaching to program: /usr/bin/qemu-system-x86_64, process 405756
[New LWP 405788]
[New LWP 405798]
[New LWP 405799]
[New LWP 405800]
[New LWP 405801]
[New LWP 405802]
[New LWP 405804]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
0x00007f549d0bdb0e in ppoll () from target:/lib64/libc.so.6
(gdb) set height 0
(gdb) set print elements 0
(gdb) set print frame-arguments all
(gdb) thread apply all backtrace

Thread 8 (Thread 0x7f53837ff640 (LWP 405804)):
#0  0x00007f549d0bda0f in poll () from target:/lib64/libc.so.6
#1  0x00007f549e4c2d1e in g_main_context_iterate.constprop () from target:/lib64/libglib-2.0.so.0
#2  0x00007f549e4716ab in g_main_loop_run () from target:/lib64/libglib-2.0.so.0
#3  0x00007f549dcfcc66 in red_worker_main.lto_priv () from target:/lib64/libspice-server.so.1
#4  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#5  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 7 (Thread 0x7f5390dfd640 (LWP 405802)):
#0  0x00007f549d0bf58b in ioctl () from target:/lib64/libc.so.6
#1  0x000055a60728ec87 in kvm_vcpu_ioctl ()
#2  0x000055a60728edc1 in kvm_cpu_exec ()
#3  0x000055a60734dc04 in qemu_kvm_cpu_thread_fn ()
#4  0x000055a6076dc0ff in qemu_thread_start ()
#5  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#6  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 6 (Thread 0x7f53915fe640 (LWP 405801)):
#0  0x00007f549d0bf58b in ioctl () from target:/lib64/libc.so.6
#1  0x000055a60728ec87 in kvm_vcpu_ioctl ()
#2  0x000055a60728edc1 in kvm_cpu_exec ()
#3  0x000055a60734dc04 in qemu_kvm_cpu_thread_fn ()
#4  0x000055a6076dc0ff in qemu_thread_start ()
#5  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#6  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 5 (Thread 0x7f5391dff640 (LWP 405800)):
#0  0x00007f549d0bf58b in ioctl () from target:/lib64/libc.so.6
#1  0x000055a60728ec87 in kvm_vcpu_ioctl ()
#2  0x000055a60728edc1 in kvm_cpu_exec ()
#3  0x000055a60734dc04 in qemu_kvm_cpu_thread_fn ()
#4  0x000055a6076dc0ff in qemu_thread_start ()
#5  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#6  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 4 (Thread 0x7f54988b7640 (LWP 405799)):
#0  0x00007f549d0bf58b in ioctl () from target:/lib64/libc.so.6
#1  0x000055a60728ec87 in kvm_vcpu_ioctl ()
#2  0x000055a60728edc1 in kvm_cpu_exec ()
#3  0x000055a60734dc04 in qemu_kvm_cpu_thread_fn ()
#4  0x000055a6076dc0ff in qemu_thread_start ()
#5  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#6  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 3 (Thread 0x7f549917b640 (LWP 405798)):
#0  0x00007f549d0bda0f in poll () from target:/lib64/libc.so.6
#1  0x00007f549e4c2d1e in g_main_context_iterate.constprop () from target:/lib64/libglib-2.0.so.0
#2  0x00007f549e4716ab in g_main_loop_run () from target:/lib64/libglib-2.0.so.0
#3  0x000055a6073c4c81 in iothread_run ()
#4  0x000055a6076dc0ff in qemu_thread_start ()
#5  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#6  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 2 (Thread 0x7f549b93a640 (LWP 405788)):
#0  0x00007f549d0c350d in syscall () from target:/lib64/libc.so.6
#1  0x000055a6076dce9a in qemu_event_wait ()
#2  0x000055a6076e56ca in call_rcu_thread ()
#3  0x000055a6076dc0ff in qemu_thread_start ()
#4  0x00007f549d19c3f9 in start_thread () from target:/lib64/libpthread.so.0
#5  0x00007f549d0c8b03 in clone () from target:/lib64/libc.so.6

Thread 1 (Thread 0x7f549bb10f00 (LWP 405756)):
#0  0x00007f549d0bdb0e in ppoll () from target:/lib64/libc.so.6
#1  0x000055a6076f4901 in qemu_poll_ns ()
#2  0x000055a6076f0485 in main_loop_wait ()
#3  0x000055a60735cdd7 in qemu_main_loop ()
#4  0x000055a607234a1e in main ()
(gdb) 




# virsh  dumpxml centos8
<domain type='kvm' id='1'>
  <name>centos8</name>
  <metadata>
    <libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0">
      <libosinfo:os id="http://centos.org/centos/8"/>
    </libosinfo:libosinfo>
  </metadata>
  <memory unit='KiB'>4096000</memory>
  <currentMemory unit='KiB'>4096000</currentMemory>
  <vcpu placement='static'>4</vcpu>
  <resource>
    <partition>/machine</partition>
  </resource>
  <os>
    <type arch='x86_64' machine='pc-q35-4.2'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <vmport state='off'/>
  </features>
  <cpu mode='custom' match='exact' check='full'>
    <model fallback='forbid'>EPYC-IBPB</model>
    <vendor>AMD</vendor>
    <feature policy='require' name='x2apic'/>
    <feature policy='require' name='tsc-deadline'/>
    <feature policy='require' name='hypervisor'/>
    <feature policy='require' name='tsc_adjust'/>
    <feature policy='require' name='clwb'/>
    <feature policy='require' name='umip'/>
    <feature policy='require' name='rdpid'/>
    <feature policy='require' name='stibp'/>
    <feature policy='require' name='arch-capabilities'/>
    <feature policy='require' name='ssbd'/>
    <feature policy='require' name='xsaves'/>
    <feature policy='require' name='cmp_legacy'/>
    <feature policy='require' name='perfctr_core'/>
    <feature policy='require' name='clzero'/>
    <feature policy='require' name='xsaveerptr'/>
    <feature policy='require' name='wbnoinvd'/>
    <feature policy='require' name='amd-stibp'/>
    <feature policy='require' name='amd-ssbd'/>
    <feature policy='require' name='virt-ssbd'/>
    <feature policy='disable' name='npt'/>
    <feature policy='disable' name='nrip-save'/>
    <feature policy='require' name='rdctl-no'/>
    <feature policy='require' name='skip-l1dfl-vmentry'/>
    <feature policy='require' name='mds-no'/>
    <feature policy='require' name='pschange-mc-no'/>
    <feature policy='disable' name='monitor'/>
    <feature policy='disable' name='svm'/>
    <feature policy='require' name='topoext'/>
  </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>destroy</on_crash>
  <pm>
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/centos8.qcow2' index='6'/>
      <backingStore/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/centos8-1.qcow2' index='5'/>
      <backingStore/>
      <target dev='vdb' bus='virtio'/>
      <alias name='virtio-disk1'/>
      <address type='pci' domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/centos8-2.qcow2' index='4'/>
      <backingStore/>
      <target dev='vdc' bus='virtio'/>
      <alias name='virtio-disk2'/>
      <address type='pci' domain='0x0000' bus='0x08' slot='0x00' function='0x0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/centos8-3.qcow2' index='3'/>
      <backingStore/>
      <target dev='vdd' bus='virtio'/>
      <alias name='virtio-disk3'/>
      <address type='pci' domain='0x0000' bus='0x09' slot='0x00' function='0x0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/var/lib/libvirt/images/centos8-4.qcow2' index='2'/>
      <backingStore/>
      <target dev='vde' bus='virtio'/>
      <alias name='virtio-disk4'/>
      <address type='pci' domain='0x0000' bus='0x0a' slot='0x00' function='0x0'/>
    </disk>
    <disk type='file' device='cdrom'>
      <driver name='qemu'/>
      <target dev='sda' bus='sata'/>
      <readonly/>
      <alias name='sata0-0-0'/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </disk>
    <controller type='usb' index='0' model='qemu-xhci' ports='15'>
      <alias name='usb'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
    </controller>
    <controller type='sata' index='0'>
      <alias name='ide'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
    </controller>
    <controller type='pci' index='0' model='pcie-root'>
      <alias name='pcie.0'/>
    </controller>
    <controller type='pci' index='1' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='1' port='0x10'/>
      <alias name='pci.1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0' multifunction='on'/>
    </controller>
    <controller type='pci' index='2' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='2' port='0x11'/>
      <alias name='pci.2'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x1'/>
    </controller>
    <controller type='pci' index='3' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='3' port='0x12'/>
      <alias name='pci.3'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x2'/>
    </controller>
    <controller type='pci' index='4' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='4' port='0x13'/>
      <alias name='pci.4'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x3'/>
    </controller>
    <controller type='pci' index='5' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='5' port='0x14'/>
      <alias name='pci.5'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x4'/>
    </controller>
    <controller type='pci' index='6' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='6' port='0x15'/>
      <alias name='pci.6'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x5'/>
    </controller>
    <controller type='pci' index='7' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='7' port='0x16'/>
      <alias name='pci.7'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x6'/>
    </controller>
    <controller type='pci' index='8' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='8' port='0x17'/>
      <alias name='pci.8'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x7'/>
    </controller>
    <controller type='pci' index='9' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='9' port='0x18'/>
      <alias name='pci.9'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0' multifunction='on'/>
    </controller>
    <controller type='pci' index='10' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='10' port='0x19'/>
      <alias name='pci.10'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x1'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <alias name='virtio-serial0'/>
      <address type='pci' domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:d4:02:c2'/>
      <source network='default' portid='643b50a3-f347-4c2e-995e-7644a7ad0a96' bridge='virbr0'/>
      <target dev='vnet0'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/4'/>
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/4'>
      <source path='/dev/pts/4'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <channel type='unix'>
      <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-1-centos8/org.qemu.guest_agent.0'/>
      <target type='virtio' name='org.qemu.guest_agent.0' state='connected'/>
      <alias name='channel0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <channel type='spicevmc'>
      <target type='virtio' name='com.redhat.spice.0' state='connected'/>
      <alias name='channel1'/>
      <address type='virtio-serial' controller='0' bus='0' port='2'/>
    </channel>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
      <address type='usb' bus='0' port='1'/>
    </input>
    <input type='mouse' bus='ps2'>
      <alias name='input1'/>
    </input>
    <input type='keyboard' bus='ps2'>
      <alias name='input2'/>
    </input>
    <graphics type='spice' port='5900' autoport='yes' listen='127.0.0.1'>
      <listen type='address' address='127.0.0.1'/>
      <image compression='off'/>
    </graphics>
    <sound model='ich9'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1b' function='0x0'/>
    </sound>
    <video>
      <model type='qxl' ram='65536' vram='65536' vgamem='16384' heads='1' primary='yes'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
    </video>
    <redirdev bus='usb' type='spicevmc'>
      <alias name='redir0'/>
      <address type='usb' bus='0' port='2'/>
    </redirdev>
    <redirdev bus='usb' type='spicevmc'>
      <alias name='redir1'/>
      <address type='usb' bus='0' port='3'/>
    </redirdev>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
    </memballoon>
    <rng model='virtio'>
      <backend model='random'>/dev/urandom</backend>
      <alias name='rng0'/>
      <address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
    </rng>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c571,c902</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c571,c902</imagelabel>
  </seclabel>
  <seclabel type='dynamic' model='dac' relabel='yes'>
    <label>+107:+107</label>
    <imagelabel>+107:+107</imagelabel>
  </seclabel>
</domain>