lspci ‐ #system #networking - five4nets/Linux-Knowledgebase GitHub Wiki

Tutorial: Using the lspci Command in Linux

The lspci command in Linux is a powerful utility for displaying information about PCI (Peripheral Component Interconnect) buses and devices connected to them, such as graphics cards, network adapters, and USB controllers. This tutorial explains the lspci command, its options, and provides multiple examples to help you understand and use it effectively.

What is lspci?

lspci is a command-line tool that lists all PCI devices in a Linux system. It retrieves details from the PCI bus and presents information like device IDs, vendor names, and device classes. It is commonly used for hardware troubleshooting, system inventory, and driver configuration.

Prerequisites

  • A Linux system with lspci installed (usually part of the pciutils package).
  • Basic familiarity with the Linux terminal.
  • Root privileges may be required for some options (use sudo).

To check if lspci is installed, run:

lspci --version

If not installed, install it using your package manager, e.g.:

  • On Debian/Ubuntu: 
    sudo apt install pciutils
  • On Fedora: 
    sudo dnf install pciutils
  • On Arch Linux: 
    sudo pacman -S pciutils

Basic Syntax

lspci [options]

Without options, lspci lists all PCI devices with basic information.

Common Options

Here are frequently used lspci options with explanations:

  • -v: Verbose mode, shows detailed information about each device.
  • -vv: Very verbose mode, provides even more details (useful for debugging).
  • -n: Numeric output, displays vendor and device IDs as numbers instead of names.
  • -nn: Shows both numeric IDs and names.
  • -k: Displays kernel drivers and modules used by each device (requires root).
  • -t: Displays a tree-like hierarchy of PCI buses and devices.
  • -d [vendor]:[device]: Filters output to show only devices matching the specified vendor and device IDs.
  • -m: Machine-readable output, useful for scripting.
  • -s [[[domain]:]bus]:][slot][.[func](/five4nets/Linux-Knowledgebase/wiki/[[domain]:]bus]:][slot][.[func): Filters devices by their PCI address (domain, bus, slot, or function).

For a full list of options, run:

man lspci

Examples

1. List All PCI Devices

To display a basic list of all PCI devices:

lspci

Sample Output:

00:00.0 Host bridge: Intel Corporation 12th Gen Core Processor Host Bridge/DRAM Registers (rev 02)
00:01.0 PCI bridge: Intel Corporation 12th Gen Core Processor PCI Express Root Port (rev 02)
01:00.0 VGA compatible controller: NVIDIA Corporation GA104 [GeForce RTX 3060] (rev a1)

This shows the PCI address, device class, vendor, and device name.

2. Display Detailed Information

Use the -v or -vv option for more details:

lspci -v

Sample Output (partial):

01:00.0 VGA compatible controller: NVIDIA Corporation GA104 [GeForce RTX 3060] (rev a1)
	Subsystem: ASUSTeK Computer Inc. Device 8816
	Flags: bus master, fast devsel, latency 0, IRQ 128
	Memory at fc000000 (32-bit, non-prefetchable) [size=16M]
	Capabilities: <access denied>

For even more details, use:

sudo lspci -vv

Note: sudo is needed for some fields like capabilities due to permission restrictions.

3. Show Numeric IDs

To display vendor and device IDs numerically (useful when names aren’t resolved):

lspci -n

Sample Output:

00:00.0 0600: 8086:4640 (rev 02)
01:00.0 0300: 10de:2503 (rev a1)

Here, 8086 is Intel’s vendor ID, and 4640 is the device ID.

To show both IDs and names:

lspci -nn

Sample Output:

00:00.0 Host bridge [0600]: Intel Corporation 12th Gen Core Processor Host Bridge/DRAM Registers [8086:4640] (rev 02)
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GA104 [GeForce RTX 3060] [10de:2503] (rev a1)

4. Display Kernel Drivers

To see which kernel drivers are in use (requires root):

sudo lspci -k

Sample Output (partial):

01:00.0 VGA compatible controller: NVIDIA Corporation GA104 [GeForce RTX 3060] (rev a1)
	Subsystem: ASUSTeK Computer Inc. Device 8816
	Kernel driver in use: nvidia
	Kernel modules: nvidia

This shows the nvidia driver is handling the GPU.

5. Display PCI Hierarchy

To visualize the PCI bus structure as a tree:

lspci -t

Sample Output:

-[0000:00]-+-00.0  Intel Corporation 12th Gen Core Processor Host Bridge/DRAM Registers
           +-01.0-[01]----00.0  NVIDIA Corporation GA104 [GeForce RTX 3060]
           +-02.0  Intel Corporation Alder Lake-P Integrated Graphics Controller
           ...

This is useful for understanding how devices are connected to buses.

5. Filter by Vendor and Device ID

To show only devices from a specific vendor and device (e.g., NVIDIA’s vendor ID 10de):

lspci -d 10de:

Sample Output:

01:00.0 VGA compatible controller: NVIDIA Corporation GA104 [GeForce RTX 3060] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GA104 High Definition Audio Controller (rev a1)

6. Filter by PCI Address

To display a specific device by its PCI address (e.g., bus 01, slot 00, function 0):

lspci -s 01:00.0

Sample Output:

01:00.0 VGA compatible controller: NVIDIA Corporation GA104 [GeForce RTX 3060] (rev a1)

7. Machine-Readable Output

For scripting, use the -m option:

lspci -m

Sample Output:

00:00.0 "Host bridge" "Intel Corporation" "12th Gen Core Processor Host Bridge/DRAM Registers" -r02 ...
01:00.0 "VGA compatible controller" "NVIDIA Corporation" "GA104 [GeForce RTX 3060]" -ra1 ...

This format is easier to parse programmatically.

Practical Use Cases

  1. Identify Hardware for Driver Installation: Use lspci -nn to find vendor and device IDs, then search for appropriate drivers.
  2. Troubleshoot Hardware Issues: Check if devices are detected correctly with lspci -v or verify drivers with lspci -k.
  3. System Inventory: Use lspci -m to generate a machine-readable list of hardware for documentation.
  4. Debug PCI Bus Conflicts: Use lspci -t to inspect the bus hierarchy.

Tips

  • Combine options for specific needs, e.g., lspci -v -s 01:00.0 for verbose output of a single device.
  • If lspci doesn’t show expected devices, ensure the hardware is properly connected and powered.
  • Use sudo for options requiring root access to avoid partial output.
  • Cross-reference vendor/device IDs with the PCI ID database (see references).

References

Conclusion

The lspci command is an essential tool for inspecting PCI devices in Linux. By mastering its options and combining them effectively, you can diagnose hardware issues, manage drivers, and document your system’s hardware configuration. Experiment with the examples above to become comfortable with lspci’s capabilities.