About glossary in README_Massflash.txt


what means signing host?

What does’signing host’ mean?

I guess it’s a’authenticated domain address’?
Or, is it a’password protected host pc’?


Thank you.

During flash a separate desktop PC running Ubuntu (probably 18.04 LTS) has the flash software, and talks to the Jetson in recovery mode (which turns the Jetson into a custom USB device which flash software understands). Some content requires signing before flashing. For example, a device tree will be available to the flash software which is just an ordinary binary .dtb file, and then a temporary version is created by tacking on a signature…it is the signature version which is actually flashed. Then, unless you’ve done something to keep the temp signed version, the signed file is deleted from the desktop PC Ubuntu host.

I have not used mass flash, but I suspect one of the arguments is such that the signed file is not deleted immediately, otherwise it would have to be resigned for every unit being flashed. Unless you’ve burned fuses for requiring a specific trusted boot key you can ignore this.

Sometimes people work with signed content using other tools (such as “dd”) to write partitions. In those cases one would use the host PC to sign the file, but offer options to not delete after signing (and to probably not actually flash). This signed version, when not auto deleted, can be used for some manual partition work.