Emergency: can't start jetson nx after sudo apt-get upgrade

hardware: jetson nx
jetpack: 4.5.1

can’t start jetson nx after I did : “sudo apt-get upgrade
I use 64G TF card, flash system by “jetson-nx-jp451-sd-card-image.zip”

could you help me to fix it ?

It is very urgent and important for me! many important code in this tf card!

how to solve this?

You can use the serial console to access the board and try to backup your system.

After that, use sdkmaanger to flash your board to latest jp4.6 version. But your data on sdcard will be erased. That is why doing the backup before it.

I am using jetson NX, and there are important code in it, I can’t erase it.
Now, the system can’t start up, how to backup it in this condition? does this method work?

The method to dump serial console is same on nano and NX.

Use the console tool to make sure your board really cannot boot or not. Sometimes it is just desktop fails to launch.

how to determine this?
I just “sudo apt-get upgrade” in original system, is there any method roll back to original system?

Are you some kind of newbie to Linux? If you can still interact with the console, then it means the device is booting up.

If the console just prints logs but not give you to type account/password, then it means failing to boot up.

I just “sudo apt-get upgrade” in original system, is there any method roll back to original system?

No way to rollback. Just reflash the board.

yes,I am not proficient in Linux
I can’t interact with console, it stacked like the pic shows
can serial console method keep my code? it is very important!

Can you attach the full log you see on your side?

this is all I can see

You shall see serial console on the host side. But not the HDMI screen on the monitor.

I copy my code out. thanks !