UC20 on RPi3B fails to boot

gbisson · February 15, 2021, 4:17pm

Hi,

I’m trying to boot latest UC20 image on my RPi3B:
http://cdimage.ubuntu.com/ubuntu-core/20/stable/current/ubuntu-core-20-armhf+raspi.img.xz

Here is the serial output I see:

gist.github.com

https://gist.github.com/gibsson/e4433d3c3c0861ba463beb1bbae1d0aa

minicom_uc20_rpi3b.txt

U-Boot 2020.10+dfsg-1ubuntu0~20.04.2 (Jan 08 2021 - 13:03:11 +0000)

DRAM:  948 MiB
RPI 3 Model B (0xa02082)
MMC:   mmc@7e202000: 0, mmcnr@7e300000: 1
Loading Environment from FAT... *** Warning - bad CRC, using default environment

In:    serial
Out:   serial
Err:   serial

This file has been truncated. show original

Seems like the boot relies on a TPM being present which isn’t the case. Any ideas?

Regards,
Gary

ijohnson · February 15, 2021, 4:35pm

Your error is not about the TPM being absent, this is the error:

[   49.768448] the-tool[[209]: FAILEDerror: cannot load metadata and verify essential bootstrap snaps [base kernel snapd gadget]: cannot validate "/run/mnt/ubuntu-seed/snaps/pi-kernel_232.snap" for snap "pi-kernel" (snap-id "jeIuP6tfFrvAdic8DMWqHmoaoukAPNbJ"), hash mismatch with snap-revision] 
Failed to start the-tool.service.

Are you sure you booted the image exactly as it is in provided on cdimage and didn’t modify it? It seems that the image was tampered with or maybe got corrupted during download.

gbisson · February 15, 2021, 5:07pm

Correct, I re-downloaded / re-flashed and it worked. Sorry for the noise.

Do you happen to know where the pi-kernel snapcraft.yaml is?

Anyway I’ll close this thread, thanks!

ijohnson · February 15, 2021, 5:19pm

Yes, the pi-kernel snapcraft.yaml is here: https://git.launchpad.net/~canonical-kernel-snaps/+git/kernel-snaps-uc20/tree/snapcraft.yaml?h=pi which has the source line which you can use to find the actual kernel source.