[conspire] Little Blue laptop

[Rick Moen]

Quoting Elise Scher (elise.scher01 at gmail.com):

> So I just hit ctrl alt delete again to try to restart. Got the following
> output on screen:
> 
> [    2.310960] PKCS#7 signature not signed with a trusted key
> [    2.311363] PKCS#7 signature not signed with a trusted key
> Similar erreo msgs for 13 more lines, with only the decimal number
> changing. Values are below for decimal numbers:
> 2,313892
> 2.315027
> 2.327113
> 2.339880
> 2.340271
> 2.358375
> 2.359458
> 2.361559
> 2.362181
> 2.369255
> 2.380620
> 3.072994
> 3.115769
 
> Gave up waiting for root device. Common problems:
> -Boot args: (cat /proc/cmdline)
>   - Check rootdelay= did the system wait long enough?)
>   - Check root= (did the system wait for the right device?)
> 
> And there is more output too.     In next email.

Thank you for taking the trouble to type all that in, which I'm sure
took a lot of time and trouble.

A bit of searching suggests 
(https://unix.stackexchange.com/questions/455189/pkcs7-signature-not-signed-with-a-trusted-key)
that this is a common problem with the Ubuntu Linux 18.04 release put
out this past April, and involves the booting kernel attempting to load
kernel modules that haven't been signed as part of UEFI Secure Boot,
with the result of the modules not loading.  As one of those modules 
was necessary for reading mass storage, the end-result was that the
kernel as unable to mount the root filesystem.

The best remedy would be to disable Secure Boot in the unit's BIOS Setup
program.  This would be my strong recommendation -- assuming your 
computer's BIOS Setup gives you that capabiity.  The alternative would
be to cryptographically sign the modules, which of course would be
damned difficult with your machine not booting.

More on that:
https://askubuntu.com/questions/773734/how-to-install-module-ko-module-without-kernel-signature-or-kernel-rebuild-in-ub
https://blog.ubuntu.com/2017/08/11/how-to-sign-things-for-secure-boot