Kernel Modules

System 2026-08-28

Kernel modules are loadable drivers and extensions that the Linux kernel can load and unload at runtime without rebooting. On Shani OS, module configuration files placed in /etc/modules-load.d/ and /etc/modprobe.d/ live in the /etc overlay and persist across all OS updates and rollbacks.

Listing and Inspecting Modules

# List all currently loaded modules
lsmod

# Show information about a module (description, parameters, dependencies)
modinfo kvm
modinfo iwlwifi
modinfo nvidia

# Show only specific fields
modinfo -F filename kvm        # path to the .ko file
modinfo -F parm kvm            # available parameters
modinfo -F depends kvm         # dependencies

# Check if a module is loaded
lsmod | grep kvm

Loading and Unloading Modules

# Load a module (for the current session only)
sudo modprobe kvm
sudo modprobe kvm_intel          # or kvm_amd depending on CPU

# Load with parameters
sudo modprobe iwlwifi 11n_disable=1
sudo modprobe usbcore autosuspend=1

# Unload a module
sudo modprobe -r kvm_intel
sudo rmmod kvm_intel             # alternative, does not handle dependencies

# Unload a module and all its dependents
sudo modprobe -r --remove-dependencies kvm_intel

# Dry run — show what would be loaded/unloaded
sudo modprobe --dry-run kvm

⚠️ rmmod fails if the module is in use. Use modprobe -r which handles the dependency chain, or check what is using it with lsmod | grep <module> and look at the "Used by" column.

Persistent Module Loading

To load a module automatically at boot, create a file in /etc/modules-load.d/. Files here are processed by systemd-modules-load.service early in the boot sequence.

# Load a single module at boot
echo "kvm_intel" | sudo tee /etc/modules-load.d/kvm.conf

# Load multiple modules
sudo tee /etc/modules-load.d/virtualisation.conf << 'EOF'
kvm
kvm_intel
vhost_net
EOF

Each file should contain one module name per line. Comments starting with # are ignored.

# Verify the service loaded all modules correctly
systemctl status systemd-modules-load.service
journalctl -u systemd-modules-load.service

Module Parameters

Module parameters can be set persistently in /etc/modprobe.d/.

# Disable 802.11n (workaround for some Wi-Fi issues)
echo "options iwlwifi 11n_disable=1" | sudo tee /etc/modprobe.d/iwlwifi.conf

# Set KVM nested virtualisation
echo "options kvm_intel nested=1" | sudo tee /etc/modprobe.d/kvm.conf
echo "options kvm_amd nested=1"   | sudo tee /etc/modprobe.d/kvm.conf   # AMD

# Set USB autosuspend delay
echo "options usbcore autosuspend=5" | sudo tee /etc/modprobe.d/usb.conf

# Verify active parameters for a loaded module
cat /sys/module/kvm_intel/parameters/nested
cat /sys/module/iwlwifi/parameters/11n_disable

Changes to /etc/modprobe.d/ take effect on the next module load. To apply immediately: unload and reload the module with modprobe -r then modprobe.

Blacklisting Modules

Blacklisting prevents a module from loading automatically. Useful for disabling a buggy driver, forcing a different driver, or preventing a conflicting module from loading alongside another.

# Blacklist a module
echo "blacklist nouveau" | sudo tee /etc/modprobe.d/blacklist-nouveau.conf

# Blacklist and also prevent loading as a dependency
sudo tee /etc/modprobe.d/blacklist-nouveau.conf << 'EOF'
blacklist nouveau
install nouveau /bin/false
EOF

The install <module> /bin/false directive is stronger — it replaces the module's install command with /bin/false, preventing it from loading even as a dependency of another module.

# Verify a module is blacklisted
cat /etc/modprobe.d/*.conf | grep blacklist

💡 Shani OS ships several blacklists by default in /usr/lib/modprobe.d/: blacklist-firewire.conf blocks firewire-core/firewire-ohci/firewire-sbp2/firewire-net (no firewire hardware is expected, and it closes off a DMA attack vector), nobeep.conf blacklists pcspkr to silence the PC speaker, noime.conf blacklists mei/mei_me (Intel vPro/AMT remote management), and disable-unused-protocols.conf disables the dccp, sctp, rds, and tipc network protocols via install <module> /bin/false to shrink the network attack surface. Run cat /usr/lib/modprobe.d/*.conf to see them; if you need to re-enable one on your own install, add the corresponding override in /etc/modprobe.d/ (part of the persistent overlay described above).

Module Aliases

Aliases let you refer to a module by a friendly name or map a hardware ID to a driver.

# Show all aliases for a module
modinfo -F alias kvm_intel

# Show which module would handle a specific hardware ID
modprobe --show-depends pci:v00008086d00001234sv...

# List all alias mappings (from modules.alias in the kernel)
cat /lib/modules/$(uname -r)/modules.alias | grep iwlwifi

Dracut and the Initramfs

On Shani OS, the initramfs is built with dracut, but it is never built standalone — Shanios boots via signed Unified Kernel Images (UKIs), and regeneration happens through gen-efi during an OS deploy. Users do not rebuild the initramfs manually.

# Force-include a module in the initramfs
echo "add_drivers+=\" virtio_blk virtio_scsi \"" | sudo tee /etc/dracut.conf.d/virtio.conf

# Verify a module is present in the current UKI's initramfs
lsinitrd | grep virtio

⚠️ Do not run bare dracut --force on Shani OS: there is no plain /boot/initramfs-linux.img to regenerate, only signed UKIs (shanios-blue.efi / shanios-green.efi). Initramfs/UKI regeneration happens via gen-efi as part of an OS deploy (sudo shani-deploy), which rebuilds and re-signs both UKIs with your dracut.conf.d/ settings applied. After changing early-boot module configuration, deploy (or run sudo gen-efi configure <slot> for the active slot) and reboot to verify before removing the previous boot slot.

Firmware

Many modules require firmware blobs that are loaded from /lib/firmware/. Shani OS ships a comprehensive linux-firmware package split by vendor — firmware is baked into the OS image at build time, and kernel + firmware updates arrive via OS deploy (sudo shani-deploy), not via a package manager. If a module reports a missing firmware file:

# Check dmesg for firmware load failures
dmesg | grep -i firmware
dmesg | grep "Direct firmware load"

# List available firmware files for a driver
ls /lib/firmware/iwlwifi*         # Intel Wi-Fi firmware
ls /lib/firmware/amdgpu/          # AMD GPU firmware

# Check which firmware package provides a file (read-only file-database query)
pacman -F /lib/firmware/iwlwifi-8265-36.ucode

If the firmware your device needs is genuinely absent from the image, you cannot add it to the read-only host yourself: request it upstream / file an issue against Shanios so it's included in the next image build. As an interim workaround, load the device from inside a Distrobox container or via Nix-packaged userspace tooling that bundles its own firmware handling.

Useful Diagnostics

# Show kernel messages related to module loading since boot
dmesg | grep -E "module|driver|firmware" | head -40

# Show all modules and their memory usage
lsmod | sort -k2 -rh

# Find which module handles a device (by PCI ID)
lspci -k | grep -A3 "VGA\|Network\|Audio"

# Find which module handles a USB device
lsusb -v 2>/dev/null | grep -E "idVendor|idProduct|Kernel driver"

# Check for module load errors at boot
journalctl -b | grep -i "module\|modprobe\|failed to load"

# Show all loaded modules with their sysfs paths
ls /sys/module/

Troubleshooting

Issue	Solution
`modprobe: FATAL: Module not found`	Module name may differ — check `modinfo` or search: `find /lib/modules/$(uname -r) -name "name"`
Module loads but device doesn't work	Check `dmesg` for firmware errors; verify firmware package is installed
`rmmod: ERROR: Module is in use`	Check the "Used by" column in `lsmod`; unload dependent modules first, or use `modprobe -r`
Module loads but wrong driver is used	Blacklist the competing module in `/etc/modprobe.d/`
Changes to `/etc/modprobe.d/` not taking effect	Unload and reload the module; or reboot; if it's an initramfs module, regenerate the UKIs via `sudo gen-efi configure <slot>` (or deploy a new OS version)
Missing firmware after OS update	Firmware ships inside the image — kernel + firmware arrive together via `sudo shani-deploy`; if your device's firmware is absent from the image, request it upstream / file an issue
Module not loading at boot despite `/etc/modules-load.d/` entry	Check `systemctl status systemd-modules-load`; verify the module name is correct with `modinfo`