PROCESSOR-SDK-AM335X: Disable login

Harsh Patel35

Intellectual 300 points

Part Number: PROCESSOR-SDK-AM335X

Hi Team,

I am working on an AM335x device with yocto build system.

Actually, i need to disable login prompt so the user can not login system using console.

Is there any way to stop login prompt only?

Thanks and regards

Harsh

over 4 years ago

0 Kemal R. Shakir over 4 years ago

TI__Guru 55345 points

Hello Harsh,

Please, see this thread. You can disable and mask serial-getty@ttyS0.service.
root@am335x-evm:~# systemctl disable serial-getty@ttyS0.service
root@am335x-evm:~# systemctl mask serial-getty@ttyS0.service
root@am335x-evm:~# systemctl daemon-reload

You can also disable these two services.
root@am335x-evm:~# systemctl disable getty@tty1.service
root@am335x-evm:~# systemctl disable serial-getty@ttyS3.service
root@am335x-evm:~# systemctl daemon-reload

If you want to disable the login prompt from OE build system. Please, add this code to <tisdk>/sources/oe-core/meta/recipes-core/systemd/systemd-serialgetty.bb.

pkg_postinst_${PN} () {
	tmp="${SERIAL_CONSOLES}"
	for entry in $tmp ; do
		ttydev=`echo $entry | sed -e 's/^[0-9]*\;//' -e 's/\;.*//'`
		if [ -n "$D" ]; then
			OPTS="--root=$D"
		fi
		systemctl $OPTS disable serial-getty@$ttydev.service
		systemctl $OPTS mask serial-getty@$ttydev.service
	done
}

Best regards,
Kemal

0 Harsh Patel35 over 4 years ago in reply to Kemal R. Shakir

Intellectual 300 points

Hi Kemal,

Thanks for your quick response.

I have tried both the suggested options as follows:

1] Added following command in the startup script:

root@am335x-evm:~# systemctl disable serial-getty@ttyS0.service
root@am335x-evm:~# systemctl mask serial-getty@ttyS0.service
root@am335x-evm:~# systemctl daemon-reload

2] Added suggested code in "<tisdk>/sources/oe-core/meta/recipes-core/systemd/systemd-serialgetty.bb" after do_install and rebuilt all the modules:

In both the cases console is still working normally without any change.

Further, i have added following "stop" command instead of "disable" command and console stops as per requirement:

root@am335x-evm:~# systemctl stop serial-getty@ttyO0.service

Please share your inputs if anything else than above command need to add

Thanks again

Regards,

Harsh

0 Kemal R. Shakir over 4 years ago in reply to Harsh Patel35

TI__Guru 55345 points

Which exact Processor SDK version and arago-base-tisdk-image-am335x-evm.tar.xz or tisdk-rootfs-image-am335x-evm.tar.xz you use?

0 Harsh Patel35 over 4 years ago in reply to Kemal R. Shakir

Intellectual 300 points

Hi Kemal,

I have verified twice and found that your previous answer is correct.

Following commands stop console, but console does not stop working with immediate effect.

root@am335x-evm:~# systemctl disable serial-getty@ttyS0.service
root@am335x-evm:~# systemctl mask serial-getty@ttyS0.service
root@am335x-evm:~# systemctl daemon-reload

It requires processor reboot to get the effect of the above commands.

Where as using following "stop" command, console stops working with immediate effect without reboot:

root@am335x-evm:~# systemctl stop serial-getty@ttyS0.service

I can understand with "stop", service will start everytime and then we are stopping it manually.

Thanks for your inputs

Regards,

Harsh

0 Kemal R. Shakir over 4 years ago in reply to Harsh Patel35

TI__Guru 55345 points

Yes, that is true.

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PROCESSOR-SDK-AM335X: Disable login