2.2. Displaying Information About a Module

⁠2.2. Displaying Information About a Module

You can display detailed information about a kernel module using the modinfo module_name command.

Note

When entering the name of a kernel module as an argument to one of the kmod utilities, do not append a .ko extension to the end of the name. Kernel module names do not have extensions; their corresponding files do.

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Example 2.1. Listing information about a kernel module with lsmod

To display information about the e1000e module, which is the Intel PRO/1000 network driver, enter the following command as root:

# modinfo e1000e
filename:       /lib/modules/3.10.0-121.el7.x86_64/kernel/drivers/net/ethernet/intel/e1000e/e1000e.ko
version:        2.3.2-k
license:        GPL
description:    Intel(R) PRO/1000 Network Driver
author:         Intel Corporation, <linux.nics@intel.com>
srcversion:     E9F7E754F6F3A1AD906634C
alias:          pci:v00008086d000015A3sv*sd*bc*sc*i*
alias:          pci:v00008086d000015A2sv*sd*bc*sc*i*
[some alias lines omitted]
alias:          pci:v00008086d0000105Esv*sd*bc*sc*i*
depends:        ptp
intree:         Y
vermagic:       3.10.0-121.el7.x86_64 SMP mod_unload modversions 
signer:         Red Hat Enterprise Linux kernel signing key
sig_key:        42:49:68:9E:EF:C7:7E:95:88:0B:13:DF:E4:67:EB:1B:7A:91:D1:08
sig_hashalgo:   sha256
parm:           debug:Debug level (0=none,...,16=all) (int)
parm:           copybreak:Maximum size of packet that is copied to a new buffer on receive (uint)
parm:           TxIntDelay:Transmit Interrupt Delay (array of int)
parm:           TxAbsIntDelay:Transmit Absolute Interrupt Delay (array of int)
parm:           RxIntDelay:Receive Interrupt Delay (array of int)
parm:           RxAbsIntDelay:Receive Absolute Interrupt Delay (array of int)
parm:           InterruptThrottleRate:Interrupt Throttling Rate (array of int)
parm:           IntMode:Interrupt Mode (array of int)
parm:           SmartPowerDownEnable:Enable PHY smart power down (array of int)
parm:           KumeranLockLoss:Enable Kumeran lock loss workaround (array of int)
parm:           WriteProtectNVM:Write-protect NVM [WARNING: disabling this can lead to corrupted NVM] (array of int)
parm:           CrcStripping:Enable CRC Stripping, disable if your BMC needs the CRC (array of int)

Here are descriptions of a few of the fields in modinfo output:

filename

The absolute path to the .ko kernel object file. You can use modinfo -n as a shortcut command for printing only the filename field.

description

A short description of the module. You can use modinfo -d as a shortcut command for printing only the description field.

alias

The alias field appears as many times as there are aliases for a module, or is omitted entirely if there are none.

depends

This field contains a comma-separated list of all the modules this module depends on.

Note

If a module has no dependencies, the depends field may be omitted from the output.

parm

Each parm field presents one module parameter in the form parameter_name:description, where:

parameter_name is the exact syntax you should use when using it as a module parameter on the command line, or in an option line in a .conf file in the /etc/modprobe.d/ directory; and,
description is a brief explanation of what the parameter does, along with an expectation for the type of value the parameter accepts (such as int, unit or array of int) in parentheses.

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Example 2.2. Listing module parameters

You can list all parameters that the module supports by using the -p option. However, because useful value type information is omitted from modinfo -p output, it is more useful to run:

# modinfo e1000e | grep "^parm" | sort
parm:           copybreak:Maximum size of packet that is copied to a new buffer on receive (uint)
parm:           CrcStripping:Enable CRC Stripping, disable if your BMC needs the CRC (array of int)
parm:           debug:Debug level (0=none,...,16=all) (int)
parm:           InterruptThrottleRate:Interrupt Throttling Rate (array of int)
parm:           IntMode:Interrupt Mode (array of int)
parm:           KumeranLockLoss:Enable Kumeran lock loss workaround (array of int)
parm:           RxAbsIntDelay:Receive Absolute Interrupt Delay (array of int)
parm:           RxIntDelay:Receive Interrupt Delay (array of int)
parm:           SmartPowerDownEnable:Enable PHY smart power down (array of int)
parm:           TxAbsIntDelay:Transmit Absolute Interrupt Delay (array of int)
parm:           TxIntDelay:Transmit Interrupt Delay (array of int)
parm:           WriteProtectNVM:Write-protect NVM [WARNING: disabling this can lead to corrupted NVM] (array of int)