Activating "noacpi" flag disables ps/2 keyboard

With recent kernel update I started to have several ( simply annoying ) dmesg BIOS bootup messages.
( According to the log message those were related to BIOS ACPI details ) .

In one of my experiments | adjustments I added the “noacpi” flag via GRUB parameters.

But for my dismay after rebooting , despite the fact that I can use the keyboard to select the grub menu afterwards , during startup the ps/2 keyboard is unresponsive…
Rebooted forcebly ( via hardware button) several times with different kernels to understand that the problem were the keyboard.
(Had to use an USB keyboard to login to the system and undone this adjustment .)

Does any have this kind of behaviour ?
Disabling the ACPI messes up the PS/2 keyboard ?
Any comments ?