OnePlus 5 users: Install OxygenOS 4.5.6!
Contains fix for crash when calling emergency numbers
OnePlus has released OxygenOS 4.5.6, which includes an important fix for all OnePlus 5 users.
The device may in some cases reboot when calling an emergency number, such as 911, 112 or 999. If this happen, the call will not be placed and you'll have to wait for the phone to start up in order to try again.
OxygenOS 4.5.6 solves this issue, so it's recommended that you update as soon as possible.