SpringBoard fails to launch on certain devices

Originator:mohammad7410
Number:rdar://35487026 Date Originated:November 11 2017
Status:Open Resolved:
Product:iOS + SDK Product Version:11.1
Classification:Serious Bug Reproducible:Always
 
Area:
Home Screen

Summary:
SpringBoard fails to start indefinitely on 11.1 on some device configurations.
Related to 35235627, now filed against SpringBoard.

Steps to Reproduce:
1. Upgrade to 11.1
2. Use device normally

Expected Results:
Device functions normally

Actual Results:
Device randomly shows a black screen at some point, phone still functions (rings when a call comes in, rings for notifications, charger sound is heard), but device has a black screen.
Rebooting the device makes it go into a SpringBoard loop. This can be deduced by hearing the charger sound multiple times if it's plugged in. After a while, the device reboots (watchdog presumably) and goes into a SpringBoard loop again. This happens indefinitely.

Updating the device again to 11.1 does not fix the issue.
Restoring the device to 11.1 and restoring a backup fixes the issue temporarily until it happens again.
Shift updating the device (while it's in the loop) to 11.0.3 completely fixes the issue and it never happens again, the device does an "Attempting data recovery" step, after which the issue never happens again. If the device is upgraded to 11.1 again, the issue returns.

This is a regression in 11.1 (and continues to be an issue in the latest 11.2 beta).
This does not affect all iPhone 7 devices, I've yet to figure out what the connection is between affected devices. This is however, not an isolated incident and does not only affect iPhone 7 devices. This issue can always be reproduced on the affected devices. See:
https://discussions.apple.com/thread/8150334?start=0&tstart=0
https://discussions.apple.com/thread/8143720?start=0&tstart=0
https://discussions.apple.com/thread/8141565?start=0&tstart=0
https://discussions.apple.com/thread/8144123?start=0&tstart=0
https://forums.macrumors.com/threads/frequent-freezing-black-screen-bootloop-after-updating-to-11-1-on-the-iphone-7-plus.2083437/

Configuration:
Two iPhone 7 devices upgraded to 11.1.

Comments


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