default or selected kernelversion does not have config value CONFIG_BINFMT_AOUT.
Result is shown for kernelversion 6.9.9
Kernel support for a.out and ECOFF binaries
modulename: binfmt_aout.ko
configname: CONFIG_BINFMT_AOUT
Linux Kernel Configuration
└─>Executable file formats
└─>Kernel support for a.out and ECOFF binaries
In linux kernel since version 2.6.12
A.out (Assembler.OUTput) is a set of formats for libraries and
executables used in the earliest versions of UNIX. Linux used
the a.out formats QMAGIC and ZMAGIC until they were replaced
with the ELF format.
The conversion to ELF started in 1995. This option is primarily
provided for historical interest and for the benefit of those
who need to run binaries from that era.
Most people should answer N here. If you think you may have
occasional use for this format, enable module support above
and answer M here to compile this support as a module called
binfmt_aout.
If any crucial components of your system (such as /sbin/init
or /lib/ld.so) are still in a.out format, you will have to
say Y here.
executables used in the earliest versions of UNIX. Linux used
the a.out formats QMAGIC and ZMAGIC until they were replaced
with the ELF format.
The conversion to ELF started in 1995. This option is primarily
provided for historical interest and for the benefit of those
who need to run binaries from that era.
Most people should answer N here. If you think you may have
occasional use for this format, enable module support above
and answer M here to compile this support as a module called
binfmt_aout.
If any crucial components of your system (such as /sbin/init
or /lib/ld.so) are still in a.out format, you will have to
say Y here.