Dear KVM Developers,
i have a strange problem with segfaults in a guest system
while compiling a linux kernel.
The basic setup (details below) is a ryzen cpu on a ab350 mainboard,
the host running ubuntu linux and guests running also debian based
linux.
Now i am compiling a vanilla linux kernel in the guest.
This will fail with random segfaults as soon as i enable a WLAN (USB
RTL8187L) connection in
the host system.
Apart from this everything is working fine.
As this WLAN is my default internet connection i did try different
virtualization setups
for almost a week until I could track down the problem.
The details:
CPU: Ryzen 7 2700X
same result using a Ryzen 5 1600
Mainboard: GA-AB350M-Gaming 3
Bios: i tested with three versions: F31, F41d, F50a
host system:
i tested with the following systems as host all x86_64
ubuntu 19.10 kernel 5.3.0-26-generic
ubuntu 19.10 kernel 5.3.0-29-generic
ubuntu 20(development) kernel 5.4.0-14-generic
kvm:
4.0 (ubutu 19.10) and 4.2.0 (ubuntu 19.10 installed from sources)
4.2.0 (ubuntu 20 dev)
guest:
ubuntu 18.10 kernel 4.18.0-10-generic
debian 10 kernel 5.4.0-3-amd64
I use libvirt to launch the guests, so two example XML files are attached,
also the hypervisor info.
I tried a lot of different settings for cpu type and and cpu pinning
without much
difference.
task:
Compile linux kernel on guest using debian linuc sources 5.4.8 or
vanilla 5.5.2
This works fine as long as I do not enable my WLAN internet connection
on the host (USB stick: NetGear, Inc. WG111v2 54 Mbps Wireless [RealTek
RTL8187L])
If I enable the WLAN (in the host) the guest starts producing random
compiler errors like these;
./include/linux/mm.h:2041:1: internal compiler error: Segmentation fault
static inline spinlock_t *pud_lockptr(struct mm_struct *mm, pud_t *pud)
^~~~~~
./include/linux/quota.h:338:1: internal compiler error: in tree_to_uhwi, at tree.h:4278
};
^
./arch/x86/include/asm/pgtable.h:163:1: internal compiler error: Segmentation fault
{
^
elf.c:685:1: internal compiler error: Segmentation fault
}
^
As soon as I disable the USB WLAN connection on the host (the USB stick
still
inserted) I can compile the kernels without any problem.
No valuable messages in the log files of the host and the guest system.
So I tested removing all Network Interfaces from the guest systems,
but this had no effect. Even without any networking a guest fails
compiling as soon as I
start the WLAN on the host system.
I checked for electrical interference by
- using a long USB cable to get the WLAN stick away from the PC ->
compilation fails
- using a laptop operating the USB WLAN stick right beside the PC ->
compilation works fine
I intensely tested the hosts RAM with memtest86+
stressed the host system with compile jobs,
even did memtests on the guests.
But everythings seems rock solid.
Does anyone have a clue, whats going on here,
or how i can debug this situation ?
Thanks,
Torsten
<domain type='kvm' id='7'>
<name>ubuntu18.10</name>
<uuid>6b2dc20e-350d-45da-bc52-a125ef9abc53</uuid>
<metadata>
<libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0";>
<libosinfo:os id="http://ubuntu.com/ubuntu/18.10"/>
</libosinfo:libosinfo>
</metadata>
<memory unit='KiB'>4194304</memory>
<currentMemory unit='KiB'>4194304</currentMemory>
<vcpu placement='static'>3</vcpu>
<resource>
<partition>/machine</partition>
</resource>
<os>
<type arch='x86_64' machine='pc-q35-4.2'>hvm</type>
<boot dev='hd'/>
<bootmenu enable='yes'/>
</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='arch-capabilities'/>
<feature policy='require' name='cmp_legacy'/>
<feature policy='require' name='perfctr_core'/>
<feature policy='require' name='clzero'/>
<feature policy='require' name='virt-ssbd'/>
<feature policy='require' name='rdctl-no'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
<feature policy='require' name='mds-no'/>
<feature policy='disable' name='monitor'/>
<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' cache='writethrough' io='threads' discard='unmap' detect_zeroes='unmap'/>
<source file='/data/qemu-vms/quadvtl04.qcow2' index='2'/>
<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='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='ich9-ehci1'>
<alias name='usb'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<alias name='usb'/>
<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'>
<alias name='usb'/>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<alias name='usb'/>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x2'/>
</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='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='52:54:00:97:b1:7e'/>
<source network='network' portid='d1a1a895-177e-45a1-8a1c-734d0302223b' bridge='virbr1'/>
<target dev='vnet0'/>
<model type='virtio'/>
<link state='up'/>
<alias name='net0'/>
<address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
</interface>
<serial type='pty'>
<source path='/dev/pts/1'/>
<target type='isa-serial' port='0'>
<model name='isa-serial'/>
</target>
<alias name='serial0'/>
</serial>
<console type='pty' tty='/dev/pts/1'>
<source path='/dev/pts/1'/>
<target type='serial' port='0'/>
<alias name='serial0'/>
</console>
<channel type='unix'>
<source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-7-ubuntu18.10/org.qemu.guest_agent.0'/>
<target type='virtio' name='org.qemu.guest_agent.0' state='disconnected'/>
<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='disconnected'/>
<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='5901' 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='apparmor' relabel='yes'>
<label>libvirt-6b2dc20e-350d-45da-bc52-a125ef9abc53</label>
<imagelabel>libvirt-6b2dc20e-350d-45da-bc52-a125ef9abc53</imagelabel>
</seclabel>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+64055:+108</label>
<imagelabel>+64055:+108</imagelabel>
</seclabel>
</domain>
<domain type='kvm' id='6'>
<name>quadvtl03</name>
<uuid>52ed6b72-6a4c-446c-a151-251411180cc8</uuid>
<metadata>
<libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0";>
<libosinfo:os id="http://debian.org/debian/10"/>
</libosinfo:libosinfo>
</metadata>
<memory unit='KiB'>8216576</memory>
<currentMemory unit='KiB'>8216576</currentMemory>
<vcpu placement='static'>4</vcpu>
<resource>
<partition>/machine</partition>
</resource>
<os>
<type arch='x86_64' machine='pc-q35-4.2'>hvm</type>
<bootmenu enable='no'/>
</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='arch-capabilities'/>
<feature policy='require' name='cmp_legacy'/>
<feature policy='require' name='perfctr_core'/>
<feature policy='require' name='clzero'/>
<feature policy='require' name='virt-ssbd'/>
<feature policy='require' name='rdctl-no'/>
<feature policy='require' name='skip-l1dfl-vmentry'/>
<feature policy='require' name='mds-no'/>
<feature policy='disable' name='monitor'/>
<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='/data/qemu-vms/quadvtl03-temp.qcow2' index='2'/>
<backingStore/>
<target dev='vda' bus='virtio'/>
<alias name='virtio-disk0'/>
<address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
</disk>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<source file='/data/qemu-vms/quadvtl03.qcow2' index='1'/>
<backingStore/>
<target dev='sda' bus='scsi'/>
<boot order='1'/>
<alias name='scsi0-0-0'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
<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='pci' index='11' model='pcie-to-pci-bridge'>
<model name='pcie-pci-bridge'/>
<alias name='pci.11'/>
<address type='pci' domain='0x0000' bus='0x09' slot='0x00' function='0x0'/>
</controller>
<controller type='virtio-serial' index='0'>
<alias name='virtio-serial0'/>
<address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
</controller>
<controller type='scsi' index='0' model='lsilogic'>
<alias name='scsi0'/>
<address type='pci' domain='0x0000' bus='0x0b' slot='0x01' function='0x0'/>
</controller>
<controller type='usb' index='0' model='ich9-ehci1'>
<alias name='usb'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x7'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci1'>
<alias name='usb'/>
<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'>
<alias name='usb'/>
<master startport='2'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x1'/>
</controller>
<controller type='usb' index='0' model='ich9-uhci3'>
<alias name='usb'/>
<master startport='4'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x1d' function='0x2'/>
</controller>
<channel type='unix'>
<source mode='bind' path='/var/lib/libvirt/qemu/channel/target/domain-6-quadvtl03/org.qemu.guest_agent.0'/>
<target type='virtio' name='org.qemu.guest_agent.0' state='disconnected'/>
<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='disconnected'/>
<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>
<video>
<model type='vga' vram='16384' heads='1' primary='yes'/>
<alias name='video0'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
</video>
<memballoon model='virtio'>
<alias name='balloon0'/>
<address type='pci' domain='0x0000' bus='0x07' slot='0x00' function='0x0'/>
</memballoon>
<rng model='virtio'>
<backend model='random'>/dev/urandom</backend>
<alias name='rng0'/>
<address type='pci' domain='0x0000' bus='0x08' slot='0x00' function='0x0'/>
</rng>
</devices>
<seclabel type='dynamic' model='apparmor' relabel='yes'>
<label>libvirt-52ed6b72-6a4c-446c-a151-251411180cc8</label>
<imagelabel>libvirt-52ed6b72-6a4c-446c-a151-251411180cc8</imagelabel>
</seclabel>
<seclabel type='dynamic' model='dac' relabel='yes'>
<label>+64055:+108</label>
<imagelabel>+64055:+108</imagelabel>
</seclabel>
</domain>
<sysinfo type='smbios'>
<bios>
<entry name='vendor'>American Megatrends Inc.</entry>
<entry name='version'>F50a</entry>
<entry name='date'>11/27/2019</entry>
<entry name='release'>5.14</entry>
</bios>
<system>
<entry name='manufacturer'>Gigabyte Technology Co., Ltd.</entry>
<entry name='product'>AB350M-Gaming 3</entry>
<entry name='version'>Default string</entry>
<entry name='serial'>Default string</entry>
<entry name='uuid'>031b021c-040d-05e1-1e06-a00700080009</entry>
<entry name='sku'>Default string</entry>
<entry name='family'>Default string</entry>
</system>
<baseBoard>
<entry name='manufacturer'>Gigabyte Technology Co., Ltd.</entry>
<entry name='product'>AB350M-Gaming 3-CF</entry>
<entry name='version'>x.x</entry>
<entry name='serial'>Default string</entry>
<entry name='asset'>Default string</entry>
<entry name='location'>Default string</entry>
</baseBoard>
<chassis>
<entry name='manufacturer'>Default string</entry>
<entry name='version'>Default string</entry>
<entry name='serial'>Default string</entry>
<entry name='asset'>Default string</entry>
<entry name='sku'>Default string</entry>
</chassis>
<processor>
<entry name='socket_destination'>AM4</entry>
<entry name='type'>Central Processor</entry>
<entry name='family'>Zen</entry>
<entry name='manufacturer'>Advanced Micro Devices, Inc.</entry>
<entry name='signature'>Family 23, Model 8, Stepping 2</entry>
<entry name='version'>AMD Ryzen 7 2700X Eight-Core Processor</entry>
<entry name='external_clock'>100 MHz</entry>
<entry name='max_speed'>4350 MHz</entry>
<entry name='status'>Populated, Enabled</entry>
<entry name='serial_number'>Unknown</entry>
<entry name='part_number'>Unknown</entry>
</processor>
<memory_device>
<entry name='size'>16384 MB</entry>
<entry name='form_factor'>DIMM</entry>
<entry name='locator'>DIMM 0</entry>
<entry name='bank_locator'>P0 CHANNEL A</entry>
<entry name='type'>DDR4</entry>
<entry name='type_detail'>Synchronous Unbuffered (Unregistered)</entry>
<entry name='speed'>2400 MT/s</entry>
<entry name='manufacturer'>Unknown</entry>
<entry name='serial_number'>00000000</entry>
<entry name='part_number'>CMK32GX4M2A2666C16</entry>
</memory_device>
<memory_device>
<entry name='size'>8192 MB</entry>
<entry name='form_factor'>DIMM</entry>
<entry name='locator'>DIMM 1</entry>
<entry name='bank_locator'>P0 CHANNEL A</entry>
<entry name='type'>DDR4</entry>
<entry name='type_detail'>Synchronous Unbuffered (Unregistered)</entry>
<entry name='speed'>2400 MT/s</entry>
<entry name='manufacturer'>A-DATA Technology</entry>
<entry name='serial_number'>8F750000</entry>
<entry name='part_number'>DDR4 2666 2OZ</entry>
</memory_device>
<memory_device>
<entry name='size'>16384 MB</entry>
<entry name='form_factor'>DIMM</entry>
<entry name='locator'>DIMM 0</entry>
<entry name='bank_locator'>P0 CHANNEL B</entry>
<entry name='type'>DDR4</entry>
<entry name='type_detail'>Synchronous Unbuffered (Unregistered)</entry>
<entry name='speed'>2400 MT/s</entry>
<entry name='manufacturer'>Unknown</entry>
<entry name='serial_number'>00000000</entry>
<entry name='part_number'>CMK32GX4M2A2666C16</entry>
</memory_device>
<memory_device>
<entry name='size'>8192 MB</entry>
<entry name='form_factor'>DIMM</entry>
<entry name='locator'>DIMM 1</entry>
<entry name='bank_locator'>P0 CHANNEL B</entry>
<entry name='type'>DDR4</entry>
<entry name='type_detail'>Synchronous Unbuffered (Unregistered)</entry>
<entry name='speed'>2400 MT/s</entry>
<entry name='manufacturer'>A-DATA Technology</entry>
<entry name='serial_number'>8E750000</entry>
<entry name='part_number'>DDR4 2666 2OZ</entry>
</memory_device>
</sysinfo>
