Proxmox on HyperV, start VM crash if more than 2815MB of memory

[gogito]

My Hardware:
Ryzen 7 7800X3D
96GB DDR5
4TB NVME
Onboard 2.5G Lan
X520-DA2 2x10G SFP+
The machine been running stable and I can use VMs with VMware and HyperV with 32GB of ram just fine. Although I can't seem to enable Nested Virtualization with VMware).

Windows 11 25H2
HyperV enabled
Nested Virtualization enabled
Proxmox 9.1 with kernel 6.17 installed in a HyperV VM with 8 cores, 16GB of memory and 128G of storage configured with ZFS.

I try a VM configured with Q35, OVMF for UEFI and 4 CPU.

If I configure the VM with 2815MB Memory or below, it will start and work fine.

But if I set it to be above that, it will instantly crash on start with this in the Proxmox journalctl: KVM: entry failed, hardware error 0xffffffff.

Does anyone has any experience with this? Seems like a QEMU issue?

Another thread with the same issue with Incus VM on QEMU:
https://discuss.linuxcontainers.org...ry-limit-greater-than-2815mib-is-set/24941/13

 

[UdoB]

You did not tell us much about your hardware. But this line:

When I start a VM with more than 2815MB of ram

calls for: have you run memtest86+? If not: run it over night, at least several hours. At least two or three full "cycles".

How much RAM does the system have? Can you start a Linux machine with that amount of Ram? (And use that RAM inside of the VM?) Does the same VM succesfully run on another node? (If you have one.) Is it a new VM or an old one? Does a fresh - installed purely for testing - VM with that OS run successfully?

There are so many details you could test... many more than I can mention here ;-)

----
Sidenote, off-topic:

Another thread with the same issue:

It gives me "Powered by Discourse, best viewed with JavaScript enabled" - so no, not available for me. (Yes, you may beat me for this one...)

 

[gogito]

You did not tell us much about your hardware. But this line:

calls for: have you run memtest86+? If not: run it over night, at least several hours. At least two or three full "cycles".

How much RAM does the system have? Can you start a Linux machine with that amount of Ram? (And use that RAM inside of the VM?) Does the same VM succesfully run on another node? (If you have one.) Is it a new VM or an old one? Does a fresh - installed purely for testing - VM with that OS run successfully?

There are so many details you could test... many more than I can mention here ;-)

----
Sidenote, off-topic:

It gives me "Powered by Discourse, best viewed with JavaScript enabled" - so no, not available for me. (Yes, you may beat me for this one...)

Hi, sorry for the lack of information in the post, I updated with more information