Questions tagged [virtio]

VirtIO is a standardized API for accessing virtual devices that a guest OS can use in a Virtual Machine. The drivers are simpler to code and give better performance than emulating real hardware devices.

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How to make use of QEMU virtio crypto device?

While trying to optimize the performance of my virtual machines, I stumbled upon a virtio device namely virtio-crypto-pci. With no tutorial and little documentations, I managed to use it as follow: [.....
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How to get write permissions on Linux host from Windows 10 guest, using virtiofs shared folders

I am trying to share a folder from an Ubuntu 20.04.3 host with a Windows 10 build 19042 (20H2) guest, using QEMU 5.2 / libvirt 7.0.0 on the host and virtio-win 0.1.208 (driver 100.85.104.20800 and ...
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/dev/vsock missing on the Slackware 14.2 VM guest

I have a problem with the missing /dev/vsock device on Slackware 14.2 virtual machine guest. I tried to append to the mkinitrd command vsock kernel module but this device isn't still present on the ...
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Slackware 14.2 huge kernel cannot load 9pnet_virtio module

I am running Slackware 14.2 virtual machine running a huge kernel 4.4.14 on UEFI mode and I have a problem with loading the 9pnet_virtio module. This module is needed for my init script. root@...
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Listing VirtIO devices from a shell in a linux guest

As the title already summarizes, is there a way (a tool or a simple command) to list available (thus recognized by a linux guest) VirtIO devices ?
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Gentoo kvm guest integrations (vmchannel)

I'm trying to get a working VMchannel to my gentoo kvm guest. I enabled the recommended kernel options for gentoo guests. As the channel appears to be a character device, I also enabled Virtio console ...
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QEMU virtio-scsi: Cannot see the number of queues after booting VM with virtio-scsi command

QEMU newbie here. I am trying to boot a VM using QEMU, for increased performance I am trying to use a virtio-scsi mounted drive. I am following the steps given here. However when I boot my VM and I ...
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virtio filesystem mounted as readonly -- why?

On the guest I mounted a directory of the host as follows: # mount -t 9p -o trans=virtio /sharepoint /share Indeed, the filesystem seems to be read/write: # mount ... /sharepoint on /share type 9p (...
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Error using virtio-fs and qemu: "Failed to read msg header. Read 0 instead of 12. Original request 1."

I'm trying to use virtio-fs to mount a folder on the host in the guest, but running into an issue. On the host I have qemu 1:5.0-5ubuntu6. virtiofsd command and output: /usr/lib/qemu/virtiofsd -f -d -...
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Shared folder between QEMU Windows guest and Linux host with virtio-fs

In QEMU 5.0 and kernel 5.4. Virtio-FS(D) was introduced for better access to shared folder on Linux host. It seems guests access the shared folder using something like FUSE technology. I found a ...
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QEMU kernel for raspberry pi 3 with networking and virtio support

I used the QEMU(qemu-system-aarch64 -M raspi3) for emulating the Raspberry pi3 with the kernel from the working image. Everything was working but there was no networking. qemu-system-aarch64 \ -...
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Transfer files between host and guest using virtio-serial

I have a Windows 10 guest with very limited network access (limited by Check-Point VPN firewall) which I access through the spice viewer. But I need to transfer files to/from the guest. I tried to ...
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How do I check if my VM is using vhost-net driver for networking

In KVM, NIC model can be set to virtio (latest) or the older e1000 (not recommended, emulated). In virtio, one has the option of using vhost-net driver or qemu. vhost-net and qemu differs in how ...
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Does VirtIO storage support discard (fstrim)?

$ uname -r 5.0.9-301.fc30.x86_64 $ findmnt / TARGET SOURCE FSTYPE OPTIONS / /dev/vda3 ext4 rw,relatime,seclabel $ sudo fstrim -v / fstrim: /: the discard operation is not supported Same VM, ...
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`cat` behaves strangely on a mounted virtio directory

When I'm in a mounted directory (9p) on my gentoo-guest and do the following: TMPDIR='./foo' # The directory './foo' exists and the name 'TMPDIR' is important cat <<EOF hello world EOF I get ...
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How can I install a Windows 10 KVM VM on a ZVOL: pick the correct virtio drivers

I was trying to install windows 10 on an NTFS formatted zvol, but I kept getting BSODs: user@ubuntu:~$ virt-install \ > --name myWINVM1 \ > --ram 4096 \ > --disk path=/guest_images2/myWINVM1....
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Accessing disk features in a QEMU/KVM VM

I recently setup a QEMU virtual machine with KVM running on Debian. The guest OS is FreeNAS (based on FreeBSD). I have given the guest access to a physical hard-disk on the host (not just a partition)....
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Why Oracle Linux doesn't recognize virtio?

On KVM-libvirt I have setup a Oracle Linux VM (Oracle Linux 7) I run it with SATA, but I want to use virtio I put the virtio disk and network..but on boot don't load the driver, or better, the driver ...
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Identify devices like virtio2 and virtio3 in QEmu

I'm running a virtual machine in QEmu. The following command in the guest VM cat /proc/interrupts | egrep 'virtio.*(input|output)' gives me the following output: 26: 0 3376 0 ...
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How can I manually trigger the virtio balloon driver on a guest?

I would like a certain Linux guest running in QEMU to release memory before the host is under memory pressure. How can I manually trigger the virtio balloon driver on a guest so that it releases as ...
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No network connectivity with virtio drivers under WinXP guest (libvirt/Qemu on Linux host)

I've been using libvirt for a couple of years now and it's worked a treat so far. Just until recently (probably after a few system updates on my Manjaro Linux host): none of my Windows (XP) guests ...
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How to merge separate logical volumes in to one physical disk?

i can see my server disk like this Disk /dev/vda: 50.0 GB Disk /dev/vdb: 50.0 GB I need to combine these two virtual block devices into single physical disk as 100GB. I have installed CentOS 7. ...
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14 votes
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Performance comparison of e1000 and virtio-pci drivers

I made a following setup to compare a performance of virtio-pci and e1000 drivers: I expected to see much higher throughput in case of virtio-pci compared to e1000, but they performed identically. ...
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Qemu disk virtio performance on Windows 10 guest

Is this speed normal? Host: 64-bit archlinux Guest: WIndows 10 64-bit Education Edition with redhat virtio stable driver, raw disk format, 32GB size, virtio enabled, kvm enabled. start command: ...
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QEMU VM using virtio drivers without kernel support / module on host?

I was trying to verify that my Win 8.1 VM running in QEMU is getting the full VirtIO benefit for the disk (raw image format) and for the network card. I read this related post and accessed the QEMU ...
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Use of virtio on QEMU without KVM

I want to write a simple driver for use inside a QEMU virtual machine, which will be communicating with the host through a respective backend special virtual device. The said driver and backend ...
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virtio network interface stops after wake

I'm running vagrant with the Virtualbox provider on my laptop and use the virtio network interface to mitigate super slow DNS lookups with the standard network device used by Virtualbox. Now putting ...
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How to handle (with LVM or DM (device mapper)) when a drive has gone away and come back as a new block device

(This correct answer is to one that bears little surface resemblance to this one. Asking the question and answering it myself with reference to that one.) Consider a virtual host environment in which ...
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virtio-kmod in /usr/ports is not compatible; what can I do?

I tried to install virtio-kmod in a FreeBSD guest. make in /usr/ports/emulators/virtio-kmod gives virtio-kmod--0.250249 not supported ${OSREL} (10.1). The ports-tree is up to date. Is that a bug or ...
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