[Android Q&A, Help & Troubleshooting] qwende:
Hi, I'm pretty sure I'm posting in the right place.

I'm trying to flash my Pixel 3 with a custom build, and it's not working. In the interest of being as clear as possible, I'll try to be as pedantic as possible about what I've done so far. I hope I am listing everything.

1. Created a custom Docker container for building (not flashing) the ROM. I installed the following on it: `apt-get update && apt-get install git-core gnupg flex bison build-essential zip curl zlib1g-dev libc6-dev-i386 libncurses5 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z1-dev libgl1-mesa-dev libxml2-utils xsltproc unzip fontconfig python3 python-is-python3 rsync wget -y`

2. I then downloaded repo by way of the following script: `export REPO=$(mktemp /tmp/repo.XXXXXXXXX)curl -o ${REPO} https://storage.googleapis.com/git-repo-downloads/repogpg --recv-key 8BB9AD793E8E6153AF0F9A4416530D5E920F5C65curl -s https://storage.googleapis.com/git-repo-downloads/repo.asc | gpg --verify - ${REPO} && install -m 755 ${REPO} /usr/local/bin/repo`

3. From here I created a working directory, and ran `repo init -u https://android.googlesource.com/platform/manifest', then `repo init -u https://android.googlesource.com/platform/manifest -b android-12.0.0_r34`.

android-12.0.0_r34 is for the pixel 3 per https://source.android.com/docs/setup/about/build-numbers#source-code-tags-and-builds

4. I then ran `repo sync -c -j8`.

5. I then ran `source build/envsetup.sh`.

6. I then downloaded both the vendor and driver installers from here ( unpacking the scripts and running them from the root of my working directory ...where I've confirmed they unpack to a vendor subdirectory each):

https://developers.google.com/android/drivers#bluelinesp1a.210812.016.c2

7. I then run `lunch aosp_blueline-userdebug` (as indicated here https://source.android.com/docs/setup/build/running#selecting-device-build).

8. I then run `m`.

9. After a couple of hours, I get a directory (/out/target/product/blueline) that contains the following \*.img files:

1. boot-debug.img 2. bootloader.img 3. dtb.img 4. persist.img 5. radio.img 6. ramdisk.img 7. ramdisk-test-harness.img 8. system\_ext.img 9. system\_other.img 10. vbmeta.img 11. boot.img 12. boot-test-harness.img 13. dtbo.img 14. product.img 15. ramdisk-debug.img 16. ramdisk-recovery.img 17. super\_empty.img 18. system.img 19. userdata.img 20. vendor.img

10. I reboot my Pixel 3 into fastboot mode (power + volume DOWN),

11. I then go back to the host machine (outside of docker). It's Ubuntu 20.04. I've got the fastboot and adb clients installed there via apt-get already.

12. I then unlock the bootloader: `fastboot flashing unlock`

13. I go into the directory with all of the \*.img files listed above, I then run `fastboot flashall -w`.

14. The following is the result:

..........Bootloader Version...: b1c1-0.4-7617406Baseband Version.....: g845-00194-210812-B-7635520Serial Number........: 8AAX0P135--------------------------------------------Checking 'product' OKAY \[ 0.060s\]Setting current slot to 'b' OKAY \[ 0.279s\]Sending 'boot\_b' (65536 KB) OKAY \[ 2.160s\]Writing 'boot\_b' OKAY \[ 0.285s\]Sending 'dtbo\_b' (8192 KB) OKAY \[ 0.360s\]Writing 'dtbo\_b' OKAY \[ 0.083s\]Sending 'vbmeta\_b' (8 KB) OKAY \[ 0.120s\]Writing 'vbmeta\_b' OKAY \[ 0.067s\]Rebooting into fastboot OKAY \[ 0.060s\]< waiting for any device >Sending 'system\_b' (4 KB) OKAY \[ 0.001s\]Updating super partition OKAY \[ 0.026s\]Deleting 'system\_a' OKAY \[ 0.005s\]Deleting 'vendor\_a' OKAY \[ 0.005s\]Resizing 'product\_b' OKAY \[ 0.005s\]Resizing 'system\_b' OKAY \[ 0.005s\]Resizing 'vendor\_b' OKAY \[ 0.005s\]Resizing 'product\_b' OKAY \[ 0.005s\]Sending sparse 'product\_b' 1/2 (262140 KB) OKAY \[ 8.438s\]Writing 'product\_b' OKAY \[ 1.850s\]Sending sparse 'product\_b' 2/2 (6028 KB) OKAY \[ 0.195s\]Writing 'product\_b' OKAY \[ 0.065s\]Resizing 'system\_b' OKAY \[ 0.006s\]Sending sparse 'system\_b' 1/4 (262140 KB) OKAY \[ 8.373s\]Writing 'system\_b' OKAY \[ 1.850s\]Sending sparse 'system\_b' 2/4 (262140 KB) OKAY \[ 8.450s\]Writing 'system\_b' OKAY \[ 0.807s\]Sending sparse 'system\_b' 3/4 (262140 KB) OKAY \[ 8.378s\]Writing 'system\_b' OKAY \[ 0.806s\]Sending sparse 'system\_b' 4/4 (27864 KB) OKAY \[ 0.892s\]Writing 'system\_b' OKAY \[ 0.121s\]Sending 'system\_a' (69060 KB) OKAY \[ 2.180s\]Writing 'system\_a' OKAY \[ 0.238s\]Resizing 'vendor\_b' OKAY \[ 0.004s\]Sending sparse 'vendor\_b' 1/2 (262140 KB) OKAY \[ 8.426s\]Writing 'vendor\_b' OKAY \[ 1.853s\]Sending sparse 'vendor\_b' 2/2 (220124 KB) OKAY \[ 7.100s\]Writing 'vendor\_b' OKAY \[ 0.693s\]Erasing 'userdata' OKAY \[ 12.740s\]Erase successful, but not automatically formatting.File system type raw not supported.Erasing 'metadata' OKAY \[ 0.007s\]Erase successful, but not automatically formatting.File system type raw not supported.Rebooting OKAY \[ 0.000s\]Finished. Total time: 94.592s

15. It appears to restart and I'm presented with the Pixel 3 in fastboot mode.

16. I then run `fastboot flashing lock`, and I confirm I wish to lock it on the phone.

17. The screen goes black for a moment, drops me back into the bootloader. The menu indicates if I press the "power" button once, I'll "start", so I press it....

18. I'm then presented with "Can't find a valid operating system. The device will not start".

And from here I'm essentially stuck. The bootloader workers as I'm able to flash many more times after this, but the system image doesn't appear to want to take over from the loader. Can anyone spot anything wrong in what I've done above? Thanks.