---------- Forwarded message ----------
From: Kenneth Freidank <kenneth.freidank@gmail.com>
Date: Sat, May 19, 2018 at 8:02 PM
Subject: Re: [Arm-dev] rainbow screen after "yum update" on 5/18/2018
To: Pablo Sebastián Greco <pablo@fliagreco.com.ar>

Thank you for the suggestion. I burned another sd card, and my PI3 booted, so it is definitely the sd card with the problem.

After booting, I was able to mount the bad sd card with a USB port adapter.

# mount /dev/sda3 /mnt <-- the main linux partition

df on /mnt showed 46% full

# mount /dev/sda1 /mnt <-- the ms-dos boot partition

df on /mnt showed 32% full but I did get an "unmounted properly", may contains errors, run fsck

On Sat, May 19, 2018 at 4:44 PM, Pablo Sebastián Greco <pablo@fliagreco.com.ar> wrote:

Hi Kenneth

El 19/5/18 a las 14:18, Kenneth Freidank escribió:

I just updated my Centos7 Pi3 "yum update" on 5/18/2018, and now I am facing a rainbow screen. Red pwr light is nice and strong, even changed power supplies. Green ACK light blinks 2 times and stays off. Screen is stuck on the rainbow - no activity, nothing, with or without the USB drive, nothing. USB drive does not power up either - nothing. Tried pressing the keys 1 to 4 at power up, then any key on multiple pwr ups, no effect. Found a similar post on https://www.raspberrypi.org/forums, search "raspberry pi3 stuck on rainbow screen after Jessie update".

Removed micro card and read files on another machine

Without listing all the files individually, kernel7.img, the dtb files bcm2708-rpi-xxx.dtb, bcm2710-rpi-xxx.dtb, bcm2835-rpi-xxx.dtb, bcm2836-rpi-xxx.dtb, gcm2837-rpi-xxx.dtb. All are dated 5/18/2018, the day of my yum update.

The kernel is kernel-4.14.27-v7.1.e7.img dated 3/19/2018.

Other files bookcode.bin, fixup*.*, LICENCE.broadcom, start*.elf, COPYING.linux all date 3/16/2018.

A file initrd-plymouth.img dates 2/26/2018.

I also see what look like older kernel files: kernel-4.9.75-v7.1.el7.img - 1/9/2018; kernel-4.9.70-v7.1.el7.img - 12/19/2017; kernel-4.9.64-v7.1.el7.img - 11/24/2017; kernel-4.4.26-v7.1.el7.img - 10/22/2016.

Looking at that amount of older kernels makes me suspect that you run out of space in /boot while updating, please check that .

Any ideas on how to downgrade to previous kernel or how to fix this? Can't get into single user mode - pressing keys on pwr up has no effect. I don't know enough about the kernel and the boot process to start messing with them. I am stuck.

Copying some of the older files in /boot should make the older kernel work, but please don't do that until we checked for disk space.
Thanks.
Pablo