MODULEPARMDESC

MODULEPARMDESC is a macro in the Linux kernel module parameter framework that attaches a human-readable description to a module parameter. It is typically used in conjunction with module_param, and its primary purpose is to improve documentation and tooling by making parameter meanings explicit in modinfo output.

Usage involves declaring a parameter with module_param and then providing a description with MODULEPARMDESC (the canonical macro in code is MODULE_PARM_DESC). For example: static int myparam = 0; module_param(myparam, int, 0644); MODULE_PARM_DESC(myparam, "Maximum number of connections"); This description is stored as metadata and shown by modinfo, helping users understand how a parameter influences a module's behavior. The macro is optional but recommended for well-documented modules.

The description provided by MODULEPARMDESC remains associated with the parameter name and is included in the module’s metadata without altering runtime behavior. It is intended to aid documentation, maintenance, and user understanding, especially for administrators deploying or configuring modules across systems.

The macro typically resides in the kernel’s parameter headers (such as linux/moduleparam.h) and is part of the broader module parameter infrastructure introduced to standardize how parameters are declared and described. It complements other parameter macros and descriptors used during module initialization and parameter parsing.

See also: module_param, modinfo, MODULE_PARM_DESC.