QEMU 9.0 available as of now

t.lamprecht

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Jul 28, 2015
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There's a new QEMU 9.0 available on the no-subscription repository.
Internal testing for that version started with the release candidates over two months ago, and our engineers could contribute several complex fixes to the stable release. Today our QEMU 9.0 package has been made available on the pve-no-subscription repository.
Our QEMU package version 9.0.0-3 contains some important stable fixes that have been developed since the original 9.0.0 release. This exact build has been in QA and the testing repository for over three weeks now, and powers most of our own production loads.

FYI, we decided to skip pushing out QEMU 8.2 due to the timing of our last point release and to reduce the amount of updates and regression (that version had some bigger internal refactoring half-way done), but we still uploaded a build of it so that you can more easily narrow down when any potential difference or even regression got introduced.

Note: While our workloads run stable on this version of QEMU, we cannot test every possible hardware and configuration combination, so we recommend testing the upgrade before applying it to mission-critical setups. As a reminder, we recommend using the most stable Enterprise repository for such production setups.

To upgrade, make sure you have configured the Proxmox VE No Subscription or Test repositories.
Either use the web-interface to refresh and then upgrade using the Node -> Updates panel, or use a console with the following standard apt commands:
Bash:
apt update
apt full-upgrade

The output of pveversion -v (or the web-interface's Node Summary -> Packages versions) should then include something like pve-qemu-kvm: 9.0.0-3

Note, as with all QEMU updates: A VM must either be completely restarted (shut it down then start it again, or use the restart command via the CLI or web-interface) or, to avoid downtime, consider live-migrating to a host that has already been upgraded to the new QEMU package version.

While we have been successfully running our production and many test loads on this version for some time now, no software is bug-free, and often such issues are related to the specific setup. So if you encounter regressions that are definitely caused by installing the new QEMU version (and not some other change), please always include the affected VM configuration and some basic HW (e.g. CPU model) and memory details.

We welcome your feedback!

Known issues:
  • Because of newer SeaBIOS, certain 32-bit guests (in particular Linux with PAE) are broken For references and workarounds see this forum post here.
 
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Looking forward to see the result of your automated testing before upgrading ours :)
I am happy to report that PVE8+QEMU9 has been integrated into our CI/CD along with PVE8+QEMU8, PVE7, and PVE6.

All regular tests have passed. Note, that we heavily focus on storage operations with iSCSI and NVMe/TCP. I am sure the Proxmox team has much more comprehensive coverage.


Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox
 
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As a data point, to instead keep using the QEMU version 8 packages you can create a file /etc/apt/preferences.d/proxmox-qemu-v8 containing this:
Package: pve-qemu-kvm
Pin: version 8.*
Pin-Priority: 1000
Proxmox will then ignore the v9 QEMU packages on that system.

Note that there's presently a bug in the v8.2 QEMU packages, so you're probably better off either using a package hold on your existing version (details here) or pinning version 8.1* instead of 8.* above until that's fixed.
 
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As a data point, to instead keep using the QEMU version 8 packages you can create a file /etc/apt/preferences.d/proxmox-qemu-v8 containing this:

Proxmox will then ignore the v9 QEMU packages on that system.
Thanks for your hint, but one might be slightly better advised to use apt-mark hold pve-qemu-kvm as a slightly simpler variant to hold back a package from upgrading. apt-mark unhold <pkgs> reveres this and apt-mark showhold shows all currently held-back packages.

Case in point, your example would still pull in the newer 8.2 update, that also includes the bug with snapshots without vmstate and VirtIO Block attacked disks (we're looking into that as of now), whereas hold'ing a package will avoid an update in any way.
I.e., while it naturally can work, it might be a bit harder to get fully right.
 
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one might be slightly better advised to use apt-mark hold pve-qemu-kvm
To freeze the exact package currently installed on a given host, sure. :)

If the desire is to allow further upgrades in the 8.x series though, then holding the package isn't the right approach. ;)
 
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1719738158342.png

Hello.
USB priority boot does not work after upgrade to qemu 9.
This option works fine with qemu version 8.



args: -drive 'if=none,id=synoboot,format=raw,file=/var/lib/vz/template/iso/arpl.img' -device 'qemu-xhci,addr=0x18' -device 'usb-storage,drive=synoboot,bootindex=1'
 
Hi,
View attachment 70551

Hello.
USB priority boot does not work after upgrade to qemu 9.
This option works fine with qemu version 8.



args: -drive 'if=none,id=synoboot,format=raw,file=/var/lib/vz/template/iso/arpl.img' -device 'qemu-xhci,addr=0x18' -device 'usb-storage,drive=synoboot,bootindex=1'
thank you for the report! I can reproduce the difference in behavior and will investigate.

EDIT: The problematic change was identified and the issue reported upstream now: https://lore.kernel.org/qemu-devel/.../T/#m70fecdb144aee440fed7a1ae9224a809c1dd8cf5
 
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If the desire is to allow further upgrades in the 8.x series though, then holding the package isn't the right approach. ;)
FYI, it's rather unlikely that the 8.x series will get further updates released, for that a graver security issue would need to be uncovered before we deem 9.0 to be stable enough to be moved to the enterprise repository. Can happen, but then we would also post a security advisory with details about the version that includes the fix, allowing one to upgrade to that manually.

Note also that with holding you would see that there are newer held back updates, while with pinning you won't see a thing directly, i.e. is much easier to forget and then cause potential graver problems in the long run (e.g., next major upgrade when we bump minimal required QEMU dependency version in our stack). I'm sure you can handle that just fine, I'm just communicating this for the users with less experience here. :)
 
Code:
$ cat 220.conf

args: -device 'nec-usb-xhci,id=usb-bus0,multifunction=on' -drive 'file=/var/lib/vz/template/iso/xpenology.img,media=disk,format=raw,if=none,id=drive-disk-bootloader' -device 'usb-storage,bus=usb-bus0.0,port=1,drive=drive-disk-bootloader,id=usb-disk-bootloader,bootindex=999,removable=on'
balloon: 0
boot:
cores: 4


xpenology usb booting error

rollback version 8
 
Hi,
Code:
$ cat 220.conf

args: -device 'nec-usb-xhci,id=usb-bus0,multifunction=on' -drive 'file=/var/lib/vz/template/iso/xpenology.img,media=disk,format=raw,if=none,id=drive-disk-bootloader' -device 'usb-storage,bus=usb-bus0.0,port=1,drive=drive-disk-bootloader,id=usb-disk-bootloader,bootindex=999,removable=on'
balloon: 0
boot:
cores: 4


xpenology usb booting error

rollback version 8
thank you for the report! It was reported already earlier in this thread, see comments #10 and for more information #12.
 
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No worries. Hopefully it doesn't have to wait until the next business day to get approved... though it might. ;)
 

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