kernelconfig_penguin
CONFIG_KGDB_TTYS0 is not available for the default architecture x86.
Result is shown for architecture ppc
default or selected kernelversion does not have config value CONFIG_KGDB_TTYS0.
Result is shown for kernelversion 5.19-rc1

ttyS0

configname: CONFIG_KGDB_TTYS0

Serial Port
└─> ttyS0

In linux kernel since version 2.6.17 (release Date: 2006-06-17)