CONFIG_VHOST_NET is missing from the `linux-kvm` flavor

[manoj reddy]

LXC VM Ubuntu Version
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.4 LTS
Release: 20.04
Codename: focal

Kernel Version
uname -a
Linux Test-Setup-01-Dell-ens5f1 5.4.0-1070-kvm #75-Ubuntu SMP Fri Jun 10 19:57:34 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

I have tried many way for installing vhost_net driver. But It didn't got any idea because it is not part of kernel.
Here the lsmod | grep vhost shows only the vhost, It doesn't shows the vhost_net driver.

Is there any solution to use the vhost_net or Is there any other way for installing vhost_net driver in kvm.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Simon Déziel (sdeziel)]

In a 20.04 VM, we can see that linux-image-kvm doesn't have the module enabled while linux-image-virtual and linux-image-generic have it:

# grep CONFIG_VHOST_NET /boot/config-5.4.0-1*
/boot/config-5.4.0-1070-kvm:# CONFIG_VHOST_NET is not set
/boot/config-5.4.0-121-generic:CONFIG_VHOST_NET=m

[manoj reddy (miniga)]

Hi Simon,
Can we get the 5.4.0-1070-kvm linux source code that your team can enable the CONFIG_VHOST_NET flag in the /boot/ floader and we can compile again.

We needed it needful. Please help us for finding the 5.4.0-1070-kvm linux source code.

Otherwise provide us the link that we can follow.

Thanks & Regards,
Manoj

[Simon Déziel (sdeziel)]

Hello Manoj,

Whether the CONFIG_VHOST_NET should be enabled or not in the linux-kvm flavor is for the kernel team to decide. If they decide it should, eventually an updated kernel will be made available.

Until then, or if they decide to keep it disabled, you can get a suitable kernel by installing the meta-package `linux-image-virtual` which has the required module enabled.