QEMU 9.2 available on pvetest and pve-no-subscription as of now

t.lamprecht said:
As the ROM is not shipped by any of our packages, nor is it open source FWICT, this not something we can ensure to fix.

But just to be sure: is this a warning only or a hard error? Is the VM configured as q35 machine or as i440fx one?
For such a thing it might be better to open a new thread, potentially others of the community came up with, or stumbled upon, a solution.
Click to expand...
Code: 
root@www:~# qm start 300
kvm: vfio: Cannot reset device 0000:00:1f.3, no available reset mechanism.
kvm: vfio: Cannot reset device 0000:00:1f.3, no available reset mechanism.
root@www:~# qemu-system-x86_64 --version
QEMU emulator version 9.1.2 (pve-qemu-kvm_9.1.2-3)
Copyright (c) 2003-2024 Fabrice Bellard and the QEMU Project developers


Same issue, downgrading to 9.1.2-3 resolved the problem.
 
mcpat said:
I get this error on my 12th gen Alder Lake (Intel Pentium Gold 8505 processor), but this error does not accure on v9.0 and I didn't changed the conf file
Code: 
kvm: -device vfio-pci,host=0000:00:02.0,id=hostpci0,bus=pci.0,addr=0x2,romfile=/usr/share/kvm/gen12_igd.rom: IGD device 0000:00:02.0 is unsupported in legacy mode, try SandyBridge or newer
Click to expand...
downgrading to 9.1.2-3 resolved the problem

By the way, lixiaoliu666's ROM is better than gangqizai's ROM

https://github.com/lixiaoliu666/intel6-14rom
 
Neobin said:
There are two reports of quite higher CPU utilization on Linux-VMs with/since the update to QEMU 9.2:
Click to expand...
Happy I found your post!

I recently also updated to pve-qemu-kvm: 9.2.0-2 , (I assume changes to VM management by qemu will only be effective on a VM reboot - see further).
Yesterday I had some maintenance going on & had to power down the node. On reboot I noticed an increase in CPU temp by about 8-10 degrees Celsius, coupled with an average increased power draw of about 10w, (yes I micromanage power consumption!) On further inspection - I found that a single VM (HAOS that runs on boot start) had increased its's CPU usage load by a factor of almost 3x.


Screenshot 2025-03-18 205110.png

I mitigated it slightly by changing the VM's processor type to host - but that is not ideal for migration nor completely effective.

Edit: I also posted on German thread here (in English).
 
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gfngfn256 said:
Happy I found your post!

I recently also updated to pve-qemu-kvm: 9.2.0-2 , (I assume changes to VM management by qemu will only be effective on a VM reboot - see further).
Yesterday I had some maintenance going on & had to power down the node. On reboot I noticed an increase in CPU temp by about 8-10 degrees Celsius, coupled with an average increased power draw of about 10w, (yes I micromanage power consumption!) On further inspection - I found that a single VM (HAOS that runs on boot start) had increased its's CPU usage load by a factor of almost 3x.


View attachment 83838

I mitigated it slightly by changing the VM's processor type to host - but that is not ideal for migration nor completely effective.
Click to expand...

In the meantime, I did also reboot my hosts because of some maintenance and now see a increased CPU utilization by a factor of two up to almost five on all my Linux-VMs too.

I guess, I will downgrade to 9.0 and put it on hold for now...
 
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Does QEMU 9.2.0 affect the CPU usage of Windows? Does disabling HPET timer affect the performance of Windows virtual machines
 
yangsm said:
Does QEMU 9.2.0 affect the CPU usage of Windows? Does disabling HPET timer affect the performance of Windows virtual machines
Click to expand...

From the link above your post:
Users confirmed that setting the hpet=off machine flag works around
the issue[0]. For Windows (7 or later) guests, the flag is already
disabled, because of issues in the past [2].

[2]: https://lists.proxmox.com/pipermail/pve-devel/2012-December/004958.html
Click to expand...
https://lore.proxmox.com/pve-devel/20250319163930.294610-1-f.ebner@proxmox.com/T/#u
 
mcpat said:
I really want to switch to q35, but please look at this topic, I get a "blurry" screen on first boot. This behaviour is also on v9.0. And with q35 there is also no startup/boot screen of windows, but I can live with it, the problem is the "blurry" screen.
Click to expand...
sorry, i missreaded.
but replyed you on the other thread.
 
yangsm said:
Does QEMU 9.2.0 affect the CPU usage of Windows? Does disabling HPET timer affect the performance of Windows virtual machines
Click to expand...
"Does QEMU 9.2.0 affect the CPU usage of Windows?"
if you use the "host" profile -> NO
But other Profiles should be updated either -> so 99,999% no either.

"Does disabling HPET timer affect the performance of Windows virtual machines"
Dunno, some years ago where Intel had broken timers, Disabling HPET increased the performance of everything, especially GUI Stutter. Or basically it fixed broken hardware timers that drift too much after longer uptimes of the Servers/Computers.
Dunno -> Because nowadays i have no clue.

On the x299 Plattform with all 7th gen CPUs (like i7-7920X), the issue cant be fixed by software, so its still broken.
But im not sure if windows with all the latest updates, or linux with all the latest kernels, have fixed it with workarounds or disabling hpet by default etc...
 
fiona said:
Regarding the issue with increased CPU usage for Linux VMs:

After checking in with upstream, we'll likely revert the problematic changes for now, see the link below. We'll likely also start disabling the HPET timer by default for never machine versions going forward.

https://lore.proxmox.com/pve-devel/20250319163930.294610-1-f.ebner@proxmox.com/T/
Click to expand...
Please do. Meanwhile, QEMU versions before 9.2 use less host CPU, as reported by others. I can also see the difference by using htop on the host. Since I also micromanage my power consumption, I’ve noticed lower power usage as well..
 
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