How to determine if a specific module is loaded in linux kernel

Question

I am just curious is there any way to determine if a particular module is loaded/installed.

$lsmod lists all modules (device driver loaded).

Is there any way to

Answer 1

The --first-time flag causes modprobe to fail if the module is already loaded. That in conjunction with the --dry-run (or the shorthand -n) flag makes a nice test:

modprobe -n --first-time $MODULE && echo "Not loaded" || echo "Loaded"

Edit 1: As @Nobody pointed out this also prints Loaded if the module does not exist. We can fix this by combining it with modinfo:

modinfo $MODULE >/dev/null 2>/dev/null &&
! modprobe -n --first-time $MODULE 2>/dev/null &&
echo "Loaded" || echo "Not loaded"

Edit 2: On some systems modprobe lives in /usr/sbin, which is not in the $PATH unless you are root. In that case you have to substitute modprobe for /usr/sbin/modprobe in the above.

Answer 2

 !/bin/sh
 # Module
 MODULE="scsi_dh_rdac"

 #Variables check if module loaded or not
 MODEXIST=/sbin/lsmod | grep "$MODULE"

 if [ -z "$MODEXIST" ]; then
       /sbin/modprobe "$MODULE" >/dev/null 2>&1
 fi

Answer 3

My short way to find if a given module is actually loaded:

cat /proc/modules | grep -c nfnetlink

which outputs

2

That 2 (TWO) means the module is LOADED. The actual output without -c shows all loaded modules with MODULENAME - -c counts the lines that contain MODULENAME. So if you have 0 (ZERO) lines as output then the module is not loaded