RHEL 6 Deployment - 22.2. Displaying Information About a Module

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22.2. Displaying Information About a Module

You can display detailed information about a kernel module by running the modinfo <module_name> command.

Module names do not end in .ko

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

For example, to display information about the e1000e module, which is the Intel PRO/1000 network driver, run:

Example 22.1. Listing information about a kernel module with lsmod

~]# modinfo e1000e
filename:       /lib/modules/2.6.32-71.el6.x86_64/kernel/drivers/net/e1000e/e1000e.ko
version:        1.2.7-k2
license:        GPL
description:    Intel(R) PRO/1000 Network Driver
author:         Intel Corporation, <[email protected]>
srcversion:     93CB73D3995B501872B2982
alias:          pci:v00008086d00001503sv*sd*bc*sc*i*
alias:          pci:v00008086d00001502sv*sd*bc*sc*i*
[some alias lines omitted]
alias:          pci:v00008086d0000105Esv*sd*bc*sc*i*
depends:
vermagic:       2.6.32-71.el6.x86_64 SMP mod_unload modversions
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)
parm:           EEE:Enable/disable on parts that support the feature (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 shorcut 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.

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:           EEE:Enable/disable on parts that support the feature (array of 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)