warning: host doesn't support requested feature: CPUID.01H:EDX.ss [bit 27]

[nbhanji]

Hello,
I have searched internet and forums regarding above issue. I had kvm initially running on proxmox 3.4 and had made a backup. Now I have install promox 4 and restored the kvm, and when I try to start it -- I get the above error.
warning: host doesn't support requested feature: CPUID.01H:EDX.ss [bit 27]
kvm: Host doesn't support requested features

HOST CPU: AMD-FX8350, guest cpu declared core2duo, 1 socket and 4 cores

pveversion -v
proxmox-ve: 4.0-16 (running kernel: 4.2.2-1-pve)
pve-manager: 4.0-48 (running version: 4.0-48/0d8559d0)
pve-kernel-4.2.2-1-pve: 4.2.2-16
lvm2: 2.02.116-pve1
corosync-pve: 2.3.5-1
libqb0: 0.17.2-1
pve-cluster: 4.0-22
qemu-server: 4.0-30
pve-firmware: 1.1-7
libpve-common-perl: 4.0-29
libpve-access-control: 4.0-9
libpve-storage-perl: 4.0-25
pve-libspice-server1: 0.12.5-1
vncterm: 1.2-1
pve-qemu-kvm: 2.4-9
pve-container: 1.0-6
pve-firewall: 2.0-12
pve-ha-manager: 1.0-9
ksm-control-daemon: 1.2-1
glusterfs-client: 3.5.2-2+deb8u1
lxc-pve: 1.1.3-1
lxcfs: 0.9-pve2
cgmanager: 0.37-pve2
criu: 1.6.0-1
zfsutils: 0.6.5-pve4~jessie

Can someone please point out why this change on 4.x? and How to fix it?

Thanks in advance.

 

[manu]

Hi
This means some CPU flags of your host system are not supported by the new qemu version.
You can change the cpu type of your VM to the more conservative "kvm64" type, and see its fix your problem.

 

[nbhanji]

I could change it, but that might/might not require me to validate my server2003sbs key. We need to recover some files from system drive. I did not want to take risk on that.

 

[manu]

Did you change host between 3.4 and 4.0 ?

 

[nbhanji]

No, same host -- we have mixed environment. We initially built vm on this host, once we were sure on the setup and functionality - we backup and then restored to production server host. One thing that I was manually able to start vm was by removing enforce option on cpu.

From the following:

TASK ERROR: start failed: command '/usr/bin/systemd-run --scope --slice qemu --unit 109831 -p 'CPUShares=1000' /usr/bin/kvm -id 109831 -chardev 'socket,id=qmp,path=/var/run/qemu-server/109831.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -vnc unix:/var/run/qemu-server/109831.vnc,x509,password -pidfile /var/run/qemu-server/109831.pid -daemonize -name vir-win2k3-01 -smp '4,sockets=1,cores=4,maxcpus=4' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000' -vga cirrus -cpu 'core2duo,vendor=GenuineIntel,check,+kvm_pv_unhalt,+kvm_pv_eoi,-kvm_steal_time,enforce'

To executing as following:
'/usr/bin/systemd-run --scope --slice qemu --unit 109831 -p 'CPUShares=1000' /usr/bin/kvm -id 109831 -chardev 'socket,id=qmp,path=/var/run/qemu-server/109831.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -vnc unix:/var/run/qemu-server/109831.vnc,x509,password -pidfile /var/run/qemu-server/109831.pid -daemonize -name vir-win2k3-01 -smp '4,sockets=1,cores=4,maxcpus=4' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000' -vga cirrus -cpu 'core2duo,vendor=GenuineIntel,check,+kvm_pv_unhalt,+kvm_pv_eoi,-kvm_steal_time'


with above command -- I can get it to start. With that in mind, I would like to have option to add stanza onto .conf file if I wanted to, rather than being put there without giving me choice.

 

[aderumier]

you can try to pass

args: -cpu .....


but, it's really not recommanded to use core2duo vcpu on amd host cpu.

This can give you vm instability/crash because of missing cpu flags.

 

[nbhanji]

I tried adding the args: -cpu check,...
This is the result, when I am trying to start the vm. It fails
-cpu 'core2duo,check,vendor=GenuineIntel,+kvm_pv_unhalt,+kvm_pv_eoi,-kvm_steal_time,enforce' -m 512 -k en-us -cpu check -device ...

This question is to the proxmox dev. Is it not possible to put the "+kvm_pv_unhalt,+kvm_pv_eoi,-kvm_steal_time,enforce'" some of the flags in the config file. This way it can be manipulated.

Point regarding instability and crash. We have had this functional in 3.x, and so far -- I/we have not had crashes. The reason I/we are reluctant to change the processor type on the restored image/vm is that some vendors and software systems base their licenses on the hardware type. In my case I had to recover the files that were on the system that is not supported anymore, and so it makes harder to change on the fly.

Right now I know how to solve the problem, but would like to retain common features that are available on cpu to function -- whether i am using test machine with AMD or production machines using INTEL. With that in mind, I would hope that some of the changes are put in place to solve this problem.

Thank you for all your help.

 

[Alfa96]

hello I have this problem in one of my servers

kvm: warning: host doesn't support requested feature: CPUID.01H:EDX.ss [bit 27]
kvm: Host doesn't support requested features
TASK ERROR: start failed: QEMU exited with code 1

??????

 

[nbhanji]

Sorry, I do not remember how I solved that. However just FYI - I select KVM/QEMU cpu because of the issue related to licensing.

 

[ClandestineAvacado]

Sorry, I do not remember how I solved that. However just FYI - I select KVM/QEMU cpu because of the issue related to licensing.

I'm having the same issue. Where did you KVM/QEMU for the CPU?

 

[gateway]

hi
i have this error:

kvm: warning: TCG doesn't support requested feature: CPUID.80000007H:EDX.invtsc [bit 8]
kvm: CPU model 'host' requires KVM or HVF
TASK ERROR: start failed: QEMU exited with code 1


and this is my cpu data
Linux pve 6.5.11-4-pve #1 SMP PREEMPT_DYNAMIC PMX 6.5.11-4 (2023-11-20T10:19Z) x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sun Jan 21 16:53:24 CET 2024 on pts/0
root@pve:~# lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Address sizes: 39 bits physical, 48 bits virtual
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Vendor ID: GenuineIntel
BIOS Vendor ID: Intel
Model name: Intel(R) Core(TM) i5-4570 CPU @ 3.20GHz
BIOS Model name: Intel(R) Core(TM) i5-4570 CPU @ 3.20GHz Fill By OEM CPU @ 3.2GHz
BIOS CPU family: 205
CPU family: 6
Model: 60
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
Stepping: 3
CPU(s) scaling MHz: 100%
CPU max MHz: 3600.0000
CPU min MHz: 800.0000
BogoMIPS: 6385.75
Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pa
t pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall
nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good
nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes6
4 monitor ds_cpl smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid
sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave a
vx f16c rdrand lahf_lm abm cpuid_fault epb invpcid_single pti ss
bd ibrs ibpb stibp fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms
invpcid xsaveopt dtherm ida arat pln pts flush_l1d
Caches (sum of all):
L1d: 128 KiB (4 instances)
L1i: 128 KiB (4 instances)
L2: 1 MiB (4 instances)
L3: 6 MiB (1 instance)
NUMA:
NUMA node(s): 1
NUMA node0 CPU(s): 0-3
Vulnerabilities:
Gather data sampling: Not affected
Itlb multihit: KVM: Mitigation: VMX unsupported
L1tf: Mitigation; PTE Inversion
Mds: Vulnerable: Clear CPU buffers attempted, no microcode; SMT disab
led
Meltdown: Mitigation; PTI
Mmio stale data: Unknown: No mitigations
Retbleed: Not affected
Spec rstack overflow: Not affected
Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl
Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitiza
tion
Spectre v2: Mitigation; Retpolines, IBPB conditional, IBRS_FW, STIBP disable
d, RSB filling, PBRSB-eIBRS Not affected
Srbds: Vulnerable: No microcode
Tsx async abort: Not affected

can someone help me?
Thank you