Questions tagged [iommu]

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Does Linux IOMMU subsystem support that "a device have mulitple master interfaces to multiple IOMMU devices"?

We are developing a device that has several ARM MMU-600(SMMU) devices. each SMMU device is connected to multiple masters. We want to use IOMMU subsystem in the Linux kernel to use SMMUs of our device ...
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1 answer
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Gnome hangs with VFIO gpu passthrough

On my computer, I have 2 discrete GPUs. I've been using VFIO to pass the second GPU to a Windows VM to work with some programs. Now I want to pass my more powerful first GPU to the Windows VM in order ...
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How to enable iommu in hyper-v

I installed centos 7.2 on Hyper-V. I am trying to enable SRIOV, for that it is required to enable the IOMMU. I want to know that how to enable the IOMMU on Hyper-V.
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how to check if iommu is enabled?

I have a centos 7.2 linux installed. I want to check if IOMMU is enabled in the system or not. How can i figure it out? Is there any /proc or /sys entry i can check to make sure is it enabled or not?
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No more iommu groups on Intel Xeon Microserver HP gen8

I have a Gen8 HP Microserver. Until the last firmware update iommu and pci pass-trough works fine (except for multi function devices like videocards with hdmi audio). Yesterday I have update the ilo ...
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2 votes
1 answer
187 views

Can a Linux Swap Partition Be Too Big?

Can a Linux swap partition be too big? I'm pretty certain the answer is, "no" but I haven't found any resources on-point, so thought I'd ask. In contrast, the main Windows swap file, ...
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Is it possible to force specific ram size in linux kernel (with unrecognized sticks)?

First of all I'm asking for an old PowerMac G5 Quad which ultimately is able to boot with 2x1GB DDR2 2x4GB DDR2 2x4GB DDR2 2x4GB DDR2 Problem is it utilizes only the first 2 gigs. The other 3 pairs ...
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Virtualization frameworks and containers effectiveness on hardware without iommu capability?

Is it worth installing VirtualBox with a Linux based distributed OS like Kali or Qubes if your hardware does not support iommu? Is there any benefit in regards to security if isolation is limited?
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1 answer
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How to isolate (reserve) GPUs with identical hardware IDs via IOMMU / dracut / kernel parameters (in VoidLinux)

I'm trying to set up pci/gpu passthrough on void. Specifically, using the vfio-pci driver to "reserve" one of the GPUs. I have been following the procedure outlined in this void-docs PR (and ...
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ACPI and AMD GPU errors while attempting to install Ubuntu or Mint

I have been trying to dual boot windows and Linux. I am facing similar problems for both Ubuntu and Mint. The attached image shows the errors that i am getting
4 votes
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How can I prevent USB drivers (EHCI) from loading on specific USB controller (PCIe card)?

I'm using Debian 10.8 with Linux Kernel 4.19.0-14. I'm trying to use IOMMU to passthrough an entire USB controller (PCI Express card), but I'm having problems. The kernel is loading the ohci_pci and ...
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1k views

Too few IOMMU groups - split?

I bought AMD RyZEN 5 2400G, Gigabyte B450M D3SH and 16GB RAM. Some elder GPU AMD Radeon HD 6XXX I took for passing through. But I was unpleasantly surprised with the IOMMU grouping. I put the GPU in ...
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2 votes
0 answers
878 views

How to fix AMD-Vi: Unable to read/write to IOMMU perf counter. at boot Void Linux

I am using an amd laptop. CPU: AMD Ryzen 5 3500U with Radeon Vega Mobile Gfx (8) @ 2.100GHz GPU: AMD ATI 03:00.0 Picasso While starting void I get this message on top AMD-Vi: Unable to read/write ...
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What is the appropiate iommu kernel parameter for Ryzen5 1600 and multiple RX580 GPU?

Reserving all the PCIe slot for RX580 prevents my PC to boot, due to such errors AMD-VI IOTLB_INV_TIMEOUT, AER: Corrected error received or kernel panic. Adding the linux parameters with iommu=soft ...
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Debian boot error: AMD-Vi: Unable to write to IOMMU perf counter

I'm booting a stable live Debian USB (with persistence) on a Windows 10 laptop with an AMD Ryzen 5 2500U processor. I should add that I've tried both the official and non-free Debian versions. The ...
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Linux, at what point a device can write to the main memory through DMA?

I am trying to figure out how and when Linux gives the permission to perform direct memory access (DMA) to the peripheral devices on PCIe. I have read how DMA is initiated in the kernel's "DMA ...
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Problem with IOMMU passthrough of i915 after Debian update

Yesterday, after six stable months I upgraded my Debian 10 box to Debian 4.19.98-1+deb10u1 (2020-04-27). I am running a KVM hypervisor and Windows 10 Pro as a VM on that box. The Win VM uses the i915 ...
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1 answer
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VT-d support enabled but IOMMU groups are missing

On a Supermicro A2SDi-8C+-HLN4F Atom C3758 system I see that VT-d support is enabled in the BIOS but I can't find any IOMMU groups under Linux (Fedora 31): $ ls /sys/kernel/iommu_groups $ The kernel ...
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4 votes
3 answers
6k views

What are the implication of using iommu=force in the boot kernel options?

I have to follow a hardening procedure for a linux os, in this procedure it tels us that the kernel option must have iommu=force. What does it do ? What could be the difference without specifying ...
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Intel CPU stepping - naming convention

I'm having trouble enabling IOMMU on Centos 8 (4.18.0-147.8.1.el8_1.x86_64) and I'm starting to think that my CPU doesn't support VT-d. On the Intel ARK page for my CPU it says "yes" for VT-x and VT-...
2 votes
0 answers
110 views

Can't access RAM from PCIe device

I use Intel Xeon with centos8 , kernel 4.18. There is also an FPGA connected to CPU through PCIe. The FPGA try to access RAM (through DMA) using physical address in RAM, but it fails in access. ...
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1 answer
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Arch Linux stuck at "Loading version 240" after modifying configs

I'm trying to get GPU passthrough to work on a VM. I've been following this video https://www.youtube.com/watch?v=6FI31QDtyy4. The differences between what I did and what he did in the video was ...
1 vote
2 answers
783 views

Passthrough Sonnet USB-C card to Windows guest via KVM and vfio

I am trying to passthrough a USB card to a guest, but I can't seem to make the VFIO driver stick, instead it seems that the host loads and takes over the card. I have a GPU successfully passed through,...
1 vote
0 answers
261 views

Share aarch64 page tables created by Linux with SMMU [closed]

I am currently working on creating a shared virtual address space in Linux arm64 on a Xilinx Zynq Ultrascale+ board. In the future it should be possible to share pointers/addresses between the Cortex ...
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1 vote
1 answer
1k views

How do I translate between qemu-system arguments and virt-install arguments so I can unify partially working commands?

I am in the process of setting up VFIO with KVM. I have the VFIO itself working, in that the VFIO'd GPU displays the UEFI shell screen when I start the VM. I am also able to create a working Windows ...
15 votes
1 answer
22k views

What are the implication of iommu=soft?

I've got new laptop at work (Lenovo A485) and there are few issues with it. It prints AMD-Vi: IOAPIC[32] not in IVRS table and kernel panic after that. So far I've figured few ways to get the system ...
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1 answer
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Ubuntu server 17.04 PCI-DMA out of IOMMU space. Status DRDY

I'm trying to install ubuntu server 17.04 on a system running 4 disks in a RAID 10 array. I'm getting a lot of errors, see attached. Can somebody please tell me what is going on. Are these errors ...
3 votes
0 answers
284 views

Is possible to re-add a removed iommu device?

I use pci passthrough. Unfortunately my card is sharing the same irq of an usb controller. I use this procedure: Find the sharing irq, in my case return 21 lspci -s 00:05:00 -vvv Find the irq ...
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3 votes
1 answer
2k views

Why does PCI passthrough not give my device to the guest OS?

I want to try PCI passthrough. I have passed an old capture video card to a Windows XP guest. IOMMU is enabled; vfio_pci is loaded I run this command: virsh nodedev-detach pci_0000_05_05_0 lspci ...
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