Hardware

iGPU PCI passthrough: new experimental packages need testers

steff22 — Thu, 08 Oct 2026 08:07:31 GMT

lspci -nn -s fra dom0 21:15 xcp-ng-test ~]# lspci -n -vvv -s 0f:00.0 0f:00.0 0300: 1002:13c0 (rev c1) (prog-if 00 [VGA controller]) Subsystem: 1002:13c0 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+ Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- Capabilities: [50] Power Management version 3 Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1+,D2+,D3hot+,D3cold+) Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- Capabilities: [64] Express (v2) Legacy Endpoint, MSI 00 DevCap: MaxPayload 256 bytes, PhantFunc 0, Latency L0s <4us, L1 unlimited ExtTag+ AttnBtn- AttnInd- PwrInd- RBE+ FLReset- DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported- RlxdOrd+ ExtTag+ PhantFunc- AuxPwr- NoSnoop+ MaxPayload 256 bytes, MaxReadReq 512 bytes DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend- LnkCap: Port #0, Speed 16GT/s, Width x16, ASPM L0s L1, Exit Latency L0s <64ns, L1 <1us ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp+ LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk+ ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- LnkSta: Speed 16GT/s, Width x16, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt- DevCap2: Completion Timeout: Range ABCD, TimeoutDis+, LTR-, OBFF Not Supported DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled LnkCtl2: Target Link Speed: 16GT/s, EnterCompliance- SpeedDis- Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS- Compliance De-emphasis: -6dB LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete+, EqualizationPhase1+ EqualizationPhase2+, EqualizationPhase3+, LinkEqualizationRequest- Capabilities: [a0] MSI: Enable- Count=1/4 Maskable- 64bit+ Address: 0000000000000000 Data: 0000 Capabilities: [c0] MSI-X: Enable+ Count=4 Masked- Vector table: BAR=5 offset=00042000 PBA: BAR=5 offset=00043000 Capabilities: [100 v1] Vendor Specific Information: ID=0001 Rev=1 Len=010 Capabilities: [270 v1] #19 Capabilities: [2a0 v1] Access Control Services ACSCap: SrcValid- TransBlk- ReqRedir- CmpltRedir- UpstreamFwd- EgressCtrl- DirectTrans- ACSCtl: SrcValid- TransBlk- ReqRedir- CmpltRedir- UpstreamFwd- EgressCtrl- DirectTrans- Capabilities: [2b0 v1] Address Translation Service (ATS) ATSCap: Invalidate Queue Depth: 00 ATSCtl: Enable-, Smallest Translation Unit: 00 Capabilities: [2c0 v1] Page Request Interface (PRI) PRICtl: Enable- Reset- PRISta: RF- UPRGI- Stopped+ Page Request Capacity: 00000100, Page Request Allocation: 00000000 Capabilities: [2d0 v1] Process Address Space ID (PASID) PASIDCap: Exec+ Priv+, Max PASID Width: 10 PASIDCtl: Enable- Exec- Priv- Capabilities: [410 v1] #26 Capabilities: [450 v1] #27 Kernel driver in use: pciback

New cisco-enic driver available for testing

Fri, 18 Sep 2026 07:31:47 GMT

Host crashes under heavy I/O (backups, VDI moves, etc.)

BrantleyHobbs — Mon, 31 Aug 2026 10:37:20 GMT

Just to update this thread. It's taking me a while to get replacement hardware assembled to a point where I can do offline testing of the host (it was running my home assistant, firewall, AD/shares, etc.). I have the host offline now and am doing some hardware testing. @dinhngtu it never did crash again. The machine ran flawlessly after that crash. I didn't try another cloud backup again though. (All the other backups ran perfectly fine.)

Support for newer Emulex LPe37xxx amd LPe36xxx Fiber channel adapters on XCP-ng 8.3 - your testing is needed

poddingue — Mon, 24 Aug 2026 08:37:37 GMT

I went digging and three threads turned up people who already have this hardware. @yeopil21 in https://xcp-ng.org/forum/topic/11799 had an LPe37102-D on a Dell R770 that never showed up at all, @jinju0504 in https://xcp-ng.org/forum/topic/11946 ended up on the -alt package on an R670, and @lukas in https://xcp-ng.org/forum/topic/8847 was running an LPe31002-M6-D with NVMe-oF back on 8.3 beta2. That last one is the older generation, so I'd guess it's the side where you most want to hear nothing regressed. Tagging them in case the cards are still on their benches.

Installation fails on MINISFORUM MS-A2 , AMD Ryzen 7 7745HX (8C/16T up to 5,1 GHz), 32 Go DDR5, 1 to SSD, PCIe x16, 2X 10G SFP+, 2X 2,5G LAN

RN0 — Mon, 03 Aug 2026 10:06:18 GMT

@poddingue, that is true, my first post here. I'll try to play with these BIOS settings again. and keep you posted. Cheers

Manual CPU feature Masks (every CPU is a potato)?

Tackyone — Tue, 14 Jul 2026 15:18:33 GMT

@MajorP93 said: What you are describing must be a storage live migration then (XenMotion). That should work across pools, yes. I stand corrected because I did not factor in this variant in my initial answer. Yes, that's it - sorry - I should have been more explicit, even if 'lumbers along' wasn't a hint //EDIT: also there is no such thing as non-pool hosts. Even a single host setup has it's own pool. Pedantic, but true I technically meant 'not hosts in the source pool' I guess.

PCIe Passthrough of Radeon iGPU fails

yannsionneau — Wed, 01 Jul 2026 01:46:30 GMT

@mgr42 Hi I published a post this morning with packages to test, if you have a non production host on which you can test it would be awesome: https://xcp-ng.org/forum/topic/12523/igpu-pci-passthrough-new-experimental-packages-need-testers Thanks! Regards, Yann

Dual video adapters - what should I see, and where?

poddingue — Mon, 29 Jun 2026 14:57:53 GMT

Your write-up is the kind of thing that saves the next person a weekend. One thing worth knowing before you commit to the whole-controller route. The passthrough page has a "Passing through Keyboards and Mice" section further down, and it says XCP-ng ships /etc/xensource/usb-policy.conf with DENY rules for mice and keyboards by default. You edit those to ALLOW, then refresh with /opt/xensource/libexec/usb_scan.py -d followed by xe pusb-scan host-uuid=. It's at https://docs.xcp-ng.org/compute/ under USB Passthrough. I have no idea whether that covers your USB-to-serial adapter, which is a different device class, and passing the whole controller may still be the cleaner setup for two discrete workstations anyway. Might be worth a mention to @Team-Hypervisor-Kernel on the display question, because that one still puzzles me.

VT-d, iommu, dmar failing - xen/qubesos troubleshooting - thinkpad e15 gen 2

poddingue — Sun, 14 Jun 2026 22:03:22 GMT

Good to hear, thanks a lot for your feedback.

Ghost PCI device - how to remove?

poddingue — Thu, 04 Jun 2026 14:32:39 GMT

That leftover NIC is probably a stale PIF that XAPI is still holding, even though the card is physically gone, and the Refresh button re-scans rather than removing it. The docs have proper "remove a physical NIC" steps that end in forgetting the old PIF with xe pif-forget: https://docs.xcp-ng.org/networking/#remove-a-physical-nic. For the GPU side, the PCI passthrough flow (hiding the device from dom0, then assigning it) is here: https://docs.xcp-ng.org/compute#detaching-a-pci-device. If the GPU still won't show up as assignable once the stale PIF is gone, it might be worth a mention to @Team-Hypervisor-Kernel.

Several errors on boot

dcabale — Mon, 25 May 2026 19:32:29 GMT

Thank you all (@olivierlambert , @teddyastie ) for your valuable responses

Audio support for Windows VM on XCP-ng

acebmxer — Mon, 18 May 2026 09:48:03 GMT

@taghjichte From my testing you would need to passthought a device for audio. If need for professional audio work then yes a pci passthough would be the perferred option. With that said. @dinhngtu As for sound I have never looked much into it but the only vm I heard make sound is from Fedora even while booted from install iso. Kubuntu or windows with xen drivers installed no audio. (find for me at the moment) While audio seems to work in Fedora from iso it seems to be limited to left channel. Local system is connected to 5.1 sound.

Server Admin Guide: A Tale of Two Servers: BIOS, GPU, and NUMA Tuning for XCP-ng: Preserving the valuable work done by Tobias Kreidl (@tjkreidl)

tjkreidl — Sat, 16 May 2026 21:08:16 GMT

@poddingue Thank you kindly! Honestly, whatever organizational structure you think is best is fine by me.

GPU share to more Windows VMs on same XCP-NG node

Aleksander — Sun, 12 Apr 2026 16:46:17 GMT

@tjkreidl I found that some Intel PRO GPU card have SRV-IO without any additional license, but this functionality is supported in Linux kernel 6.12 and up. I hope in new XCP-NG will have 6.12+ and support GPU sharing.

HCL - GPUs

Tue, 07 Apr 2026 22:34:41 GMT

XCP-ng 8.3: Broadcom BCM57414 `bnxt_en` Driver Fails to Probe on HPE DL380a Gen12

olivierlambert — Fri, 03 Apr 2026 12:49:15 GMT

Very cool, thanks for the feedback @maximsachs !

Is v8.3 NUMA aware?

yannsionneau — Tue, 24 Mar 2026 03:03:04 GMT

Hello @codemercenary In theory Xen is NUMA aware (See https://wiki.xenproject.org/wiki/Xen_on_NUMA_Machines) so you would leave memory interleaving option of the BIOS off so that Xen does what it thinks is necessary. But these kinds of settings are very very workload sensitive and in fact it's usually a good idea to just test what works best for you. Regards, Yann

Host stuck at grub on reboot

AshleyDe — Fri, 06 Mar 2026 16:48:43 GMT

I've seen this happen after a BIOS update or if a CMOS battery starts failing. Sometimes the motherboard resets to 'Legacy' instead of 'UEFI' (or vice versa), and GRUB just loses its mind because it can't find the partition it expects. It’s worth a quick check in your firmware settings to make sure the boot mode and the drive order haven't shifted on you.

AMD 'Barcelo' passthrough issues - any success stories?

yannsionneau — Sat, 28 Feb 2026 12:17:27 GMT

@timemaster5 @dustyarmstrong I published a thread with packages to test, if you have a non production host on which you can test it would be awesome: https://xcp-ng.org/forum/topic/12523/igpu-pci-passthrough-new-experimental-packages-need-testers Thanks! Regards, Yann

very slow disk ssd support all vms xcp-ng8.2.1

ThasianXi — Fri, 20 Feb 2026 04:36:01 GMT

@comdirect Use this command: (replace sda in the command below with the relevant device) cat /sys/block/sda/queue/scheduler The active scheduler will be enclosed in brackets. e.g. noop deadline [cfq] For multiple drives use: grep "" /sys/block/*/queue/scheduler

Host lockups during data transfers

fluxtor — Thu, 19 Feb 2026 11:42:44 GMT

@AtaxyaNetwork Hi yes, Sorry I'm not super experienced in this area at all. I'm SSHd into the host and just ran dmesg -T in the root. [image: 0583e493-4d70-40b7-afc0-a88b0d9fd1a4-image.png]

Host compatibility

Danp — Wed, 18 Feb 2026 23:28:18 GMT

@acebmxer There are older versions of the guest tools still available on Github.

ASUS NUC NUC14MNK-B LAN problems

yann — Wed, 18 Feb 2026 09:56:14 GMT

Drivers are actually in @Team-Hypervisor-Kernel scope nowadays

Dell R720 | 620 PCI-E Pass Through

jbamford — Sun, 15 Feb 2026 23:47:53 GMT

Good afternoon, I have resolved the problem. Domo was trying to use the network Controller. Fixed it by using, /opt/xensource/libexec/xen-cmdline --set-dom0 "xen-pciback.hide=(0000:44:00.0)(0000:44:00.1)(0000:45:00.0)(0000:45:00.1)" reboot xl pci-assignable-list Xen Orchestra now allows PCI Networking Card to Pass-Through the VM. Regards

Recommended DELL Hardware ?

Danp — Thu, 12 Feb 2026 15:02:14 GMT

@DustinB said in Recommended DELL Hardware ?: Doesn't using non-shared storage ultimately cause the VM to be started on the other host? No. Live migration can occur between hosts even if: the VDI are located on non-shared storage the hosts are in completely different pools For the cross pool migration to succeed, both pools need to support a common instruction set. Otherwise, use the Warm Migration feature that does reboot the VM so that it is running the correct instruction set on the destination host.