/sbin/modinfo

The /sbin/modinfo command in Linux is used to display information about kernel modules installed on the system. Here’s an in-depth explanation of what modinfo does and how it is used:

Purpose of modinfo

1. Module Information:

   • modinfo provides detailed information about kernel modules, including their parameters, dependencies, authorship, version, license, and more.

   • This command helps administrators and users understand the capabilities and requirements of installed kernel modules.

2. Usage Scenarios:

   • Module Troubleshooting: Use modinfo to investigate module details when troubleshooting issues related to specific hardware or functionality.

   • Dependency Analysis: Check module dependencies (depends) to understand which other modules are required for proper operation.

   • Configuration and Tuning: Review module parameters (parm) to adjust their behavior or performance.

How to Use modinfo

• Basic Usage: To display information about a specific kernel module, specify its name as an argument to modinfo.

  modinfo module_name

  Replace module_name with the name of the kernel module you want to query.

• Example:

  modinfo usb_storage

  This command would display detailed information about the usb_storage module, including its version, description, license, dependencies, parameters, and more.

• Listing All Modules: Running modinfo without any arguments lists information about all installed kernel modules.

  modinfo

• Verbose Output: Adding -v provides verbose output, showing additional details such as module aliases and the path to the module file.

  modinfo -v module_name

Example Output

Here's a sample output of modinfo usb_storage:

filename:       /lib/modules/5.4.0-84-generic/kernel/drivers/usb/storage/usb-storage.ko
alias:          usb:v0BC2p3001d*dc*dsc*dp*ic*isc*ip*in*
alias:          usb:v058Fp6366d*dc*dsc*dp*ic*isc*ip*in*
...
depends:        usb-storage
retpoline:      Y
name:           usb_storage
...
description:    USB Mass Storage driver for Linux
...
license:        GPL
...
author:         Alan Stern <[e-mail]>
...
vermagic:       5.4.0-84-generic SMP mod_unload 

Conclusion

modinfo is a valuable command-line tool for querying and understanding kernel modules in Linux systems. By providing detailed insights into module characteristics and dependencies, modinfo helps administrators manage modules effectively, troubleshoot issues, and optimize system performance. Incorporating modinfo into regular system administration tasks enhances the overall reliability and functionality of Linux deployments by ensuring informed decisions regarding kernel module configuration and management.