How to Install Kernel 5.11 From Source on Elementary OS Guide

Configuring

5. 5. Configuring Kernel

   So now to Configure Elementary OS Linux Custom Kernel
   First, access the Kernel Source with::

   cd linux*

   Then copy the current Configuration File into the New Kernel Source:

   sudo find /boot/ \( -iname "*config*" -a -iname "*`uname -r`*" \) -exec cp -i -t ./ {} \;

   mv *`uname -r`* .config

   This mystics because the default Configuration File may have a variable composition including “config” and the Kernel Version.
   In case of a Chrooted System instead you may look up the available Kernels with:

   ls /boot | grep config

   The grep Command refine the output List showing only the entries Matching the Keyword.
   Again fix the Configuration File editing it with nano and commenting out like:

   sudo nano .config

   Use Ctrl+w to search for “CONFIG_SYSTEM_TRUSTED_KEYS” on nano.
   And comment out the Line like:

   #CONFIG_SYSTEM_TRUSTED_KEYS

   Or else try to Set it like:

   CONFIG_SYSTEM_TRUSTED_KEYS=""

   Ctrl+x to Save & Exit.
   Else to reconfigure the Kernel use:

   sudo make menuconfig

   For instructions see: How to Configure a Build Kernel.