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22.7 Legacy Series / Re: Recurring Kernel Panics - Fatal trap 12: page fault while in kernel mode
« on: September 18, 2022, 05:06:43 pm »
Troubleshooting update:
TLDR: Potential solution found - use kvm64 cpu with aes flag enabled.
I have tried different CPU settings on Proxmox:
kvm64: -mitigation flags +aes = stable Only setup with more than 20hs uptime. I reached 48hs.
Note: kvm64 is a legacy very old Pentium Based CPU with very little flags. Adding AES helps a lot. I didn't see apreciable CPU performance loss on 2.5gbit loads as compared to host-passthrough. NICs are still passthrough and also very stable.. Mitigations are enabled on host kernel.
qemu64: -mitigation flags +aes = unstable Crashes in sub 20hs as usual.
Crashes the same way as cpu passthrough or host-model
other cpu models I tried a few without success. Considering that qemu64, which is a very migration safe CPU, has crashed, I won't bother trying to cherry-pick which flag is causing the issue.
@yourfriendarmando: I believe it is less a hardware issue than a poor BIOS development. I'm sure the work put in by name brand solutions if far more refined. This CPU simplification workaround is a nice find, especially for users in 3rd world countries where importing is extremely expensive and chinese solutions such as these are a decent bang for the buck, although requires work.
@Nearly9892 and other repliers, considering this find, I don't think I'll bother with Proxmox. It would be worth it if I was clusterizing. But for this homelab single deployment it looks overkill.
Next step: I'll go back to the ubuntu ssd and replicate vm settings there, check if it remains as stable as in proxmox - it should, considering the underlying hypervisor is the same, and so far crashing behaviour between proxmox and ubuntu +kvm has been identical.
TLDR: Potential solution found - use kvm64 cpu with aes flag enabled.
I have tried different CPU settings on Proxmox:
kvm64: -mitigation flags +aes = stable Only setup with more than 20hs uptime. I reached 48hs.
Code: [Select]
2 (1 sockets, 2 cores) [kvm64,flags=-pcid;-spec-ctrl;-ssbd;-ibpb;-virt-ssbd;-amd-ssbd;-amd-no-ssb;+aes]
Note: kvm64 is a legacy very old Pentium Based CPU with very little flags. Adding AES helps a lot. I didn't see apreciable CPU performance loss on 2.5gbit loads as compared to host-passthrough. NICs are still passthrough and also very stable.. Mitigations are enabled on host kernel.
qemu64: -mitigation flags +aes = unstable Crashes in sub 20hs as usual.
Crashes the same way as cpu passthrough or host-model
other cpu models I tried a few without success. Considering that qemu64, which is a very migration safe CPU, has crashed, I won't bother trying to cherry-pick which flag is causing the issue.
@yourfriendarmando: I believe it is less a hardware issue than a poor BIOS development. I'm sure the work put in by name brand solutions if far more refined. This CPU simplification workaround is a nice find, especially for users in 3rd world countries where importing is extremely expensive and chinese solutions such as these are a decent bang for the buck, although requires work.
@Nearly9892 and other repliers, considering this find, I don't think I'll bother with Proxmox. It would be worth it if I was clusterizing. But for this homelab single deployment it looks overkill.
Next step: I'll go back to the ubuntu ssd and replicate vm settings there, check if it remains as stable as in proxmox - it should, considering the underlying hypervisor is the same, and so far crashing behaviour between proxmox and ubuntu +kvm has been identical.