Rpm based distro - Red Hat/CentOS/Fedora Core/Suse Linux
First find out all installed kernel version with following command:
# rpm -qa | grep kernel-smp
or
# rpm -qa | grep kernel
Output:
kernel-smp-2.6.9-42.EL kernel-smp-2.6.9-42.0.3.EL kernel-smp-2.6.9-42.0.8.EL
I've total 3 different kernel installed. To remove kernel-smp-2.6.9-42.EL type command:
# rpm -e kernel-smp-2.6.9-42.EL
OR
# rpm -vv -e kernel-smp-2.6.9-42.EL