After auto reboot, Phone stuck on an unresponsive fastboot screen.

daszo

Hello all, I have been using Graphene OS for the last 10 months and got my first really big issue today.

My phone auto rebooted during the night and when I awoke it was showing the fast boot screen. The warning sign that is normally yellow was now red. The phone was totally unresponsive. I tried to select start by pressing the power key, but no response. Also cycling the options using the power keys does not work.

I was able to fore reboot it by holding the power button. But it just returned to this screen. I tried to force reboot into recovery mode by holding arrow down, but nothing it just returned to the same screen. I then connected it to my laptop and ran fast reboot recovery. But it just rebooted and returned to the same screen.

I went to gemini for help and it tells me that my phone is bricked and that I have to replace the bootloader. I really hope not, but I also don't know if it's right. Anybody that can help me?

Johnnyloans

Greetings,

Your data will be safe if a sideload is successful. Keep in mind there are 2 boot slots--2 copies of the OS.

choose 1 of these 2 files to sideload.
Regular:
https://releases.grapheneos.org/husky-ota_update-2026050700.zip

This is the security preview version (recommended)
https://releases.grapheneos.org/husky-ota_update-2026050701.zip

If you're unsure, they both work.

Check what boot slot you're on before sideloading successfully. It says on the bootloader screen, a or b.
If the phone reboots before you sideload, check again. After sideloading, let it boot up twice, the boot slot may change. It might work on the 1st or 2nd boot up. Sideload to both boot slots if the 1st try is successful but it reboots twice without getting to your lock screen.

Here are the instructions.
https://grapheneos.org/usage#updates-sideloading

Goodluck. Let us know how it goes

daszo

Johnnyloans Thank you for your quick response, I followed the instructions but got stuck at "adb reboot recovery". That is as, I understand it, because I am stuck in the bootloader. To restart in recovery from the bootloader I do "fast reboot recovery" but that just puts me back into boot screen and its still unresponsive.

Johnnyloans

daszo

What if you hold down the power button for a minute straight without letting go, it should turn off, then turn the phone back on.

daszo

Johnnyloans wow for some reason I tried it again and now it is responsive and in recovery mode. I will update you if I am further

daszo

Johnnyloans Okey It just rebooted from recovery mode on its own and now I am in again. Weird. Do you know if there are any logs so that I can check on what was stopping me from booting? Thanks for the help btw!

Johnnyloans

daszo

Keep good backups of contacts, calendar events if not in the cloud, notes, messages, pictures, etc

This issue or others could happen again and possibly more frequently. It could be a sign of a hardware issue.

If your threat model permits it, you could set auto reboot to 12 hours or something to not have it trigger overnight.

Johnnyloans

Nicely done!

You can have your phone build a bugreport.zip file.

2 Methods to get it:

You can run this command (phone > debugging enabled)
- adb bugreport bugreport.zip
Turn on Developer options > go to developer options > Near the top is 'bug report' tap it > full report`
- it'll think for several minutes > a notification pops up saying it's done > hit the share button > pick something like your file manager to save the file. (If you don't succeed in sharing it, start a new bugreport)

inside of the zip are several: FS/data/misc/recovery/last_ksmg files
These are kernel logs from each time your phone was on--between boot up and shutdown/off.

Last_kmsg is right now--boot up until this point in time.
So, last_kmsg.1 is the previous time the phone was on which will be your crash. There might be something big near the end of the file (Keep in mind, many functional apps have "errors" and "warnings" all the time.)

Might have something useful. The phone might have not had time to record an error during a catastrophic issue forcing it off.

Other things not relevant right now:
FS/data/anr/*
dumps of apps that froze and were killed.

FS/data/tombstones/*
App crash dumps. 0 oldest. highest number newest.

happy fishing

Developer-Dude

Johnnyloans Nicely done!

You can have your phone build a bugreport.zip file.

2 Methods to get it:
You can run this command (phone > debugging enabled)
adb bugreport bugreport.zip

Turn on Developer options > go to developer options > Near the top is 'bug report' tap it > full report`
it'll think for several minutes > a notification pops up saying it's done > hit the share button > pick something like your file manager to save the file. (If you don't succeed in sharing it, start a new bugreport)

inside of the zip are several: FS/data/misc/recovery/last_ksmg files
These are kernel logs from each time your phone was on--between boot up and shutdown/off.

Last_kmsg is right now--boot up until this point in time.
So, last_kmsg.1 is the previous time the phone was on which will be your crash. There might be something big near the end of the file (Keep in mind, many functional apps have "errors" and "warnings" all the time.)

Might have something useful. The phone might have not had time to record an error during a catastrophic issue forcing it off.

Other things not relevant right now:
FS/data/anr/*
dumps of apps that froze and were killed.

FS/data/tombstones/*
App crash dumps. 0 oldest. highest number newest.

happy fishing

And @daszo turn OFF Developer Options after if you do this. Not recommended to have them on

daszo

Johnnyloans Yes, that's the first thing I did. It's a bit of a wake up call to start backing up my stuff. Could not figure out what caused the crash. So I'll just be careful going forward. Thanks for the help!

hb0mb

Same thing happened to me this morning. Holding the power button for a minute worked for me, too. Thanks for the thread, info & assistance!