How to find out all Kernel Boot Parameters

how to find out all the available kernel’s command-line parameters (kernel boot parameters)?

It locates in the following file of kernel source code package.


how to permanently add/change a kernel boot parameter?

Edit file /etc/default/grub or /etc/default/grub.d/xxx.cfg and add the parameter like that (replace aaa=bbb into real parameter)


and update grub

sudo update-grub
sudo reboot

view present kernel boot parameter

cat /proc/cmdline
### or
dmesg | grep "Command line"

online ref:


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