With the thermal throttling issue fixed, Apple is now investigating a new issue which may be related to the T2 chipset powering its 2018 MacBook Pro models. Some 2018 MacBook Pro users recently started complaining of a kernel panic issue with their new MacBook Pro.
T2 Chipset causing kernel panic issue
The 2018 MacBook Pro kernel panic issue came to light after some users took to online forums to discuss the issue, its symptoms and potential causes. Many affected users also shared crash logs from their devices, and one term that cropped up often was “bridgeOS,” which is the on-board firmware responsible for managing the T2 chip. The crashes usually occur when the system is resting and not while it is in heavy use.
“Looking at the Kernel Panic dumps, looks like someone may have been working on it, as the Kernel Version got bumped from 17.3.0 in January to 17.4.0 yesterday and it feels like I’m seeing fewer panics,” one affected user said, suggesting Apple is working on the issue.
In the kernel panic issue, the computer’s OS encounters an internal fatal error from which it is unable to recover safely. Thus, it reboots to minimize the risk of data loss. When a system encounters this issue, it tells you to restart your Mac.
Apple’s iMac Pro, which also uses the T2 chipset, faced a similar issue. Chances are that the issue is with Apple’s T2 chipset or with the bridgeOS firmware. On the iMac Pro, the issue is affecting users connecting storage devices to the Thunderbolt 3 port. On the MacBook Pro, users with daisy-chained storage devices on their systems are experiencing the issue.
Apple came up with the T1 custom chip for the 2016 MacBook Pro with Touch Bar. At the time, the chip was responsible for controlling the Touch Bar. The T2 chipset, which was launched with the iMac Pro last year, is far superior to the first-generation chipset in handling responsibilities like storage encryption, the always-on “Hey Siri” command, authenticating Touch ID, secure boot, image signal processing, controlling audio and more.
A fix for the 2018 MacBook Pro?
Apple told MacRumors it is not a widespread issue, and though it has not received any official complaints or reports about the issue, it has started an investigation to develop a long-term solution. For the time being, Apple is offering several temporary fixes, like turning off Power Nap and disabling FileVault.
Apple support representatives are also asking affected users to reinstall macOS and disable all the functions handled by the T2 chipset. Though this is not a permanent fix, it has worked in some cases.
Apple is also asking users to update their MacBook Pros with the macOS High Sierra Supplemental Update, which came earlier this week. The update includes improvements in reliability and stability and a bug fix for excessive thermal throttling. However, the update does not seem to address the kernel panic issue.
Thermal throttling now fixed
Though the fix for excessive thermal throttling arrived only this week, users have been complaining about it for a long time. Apple acknowledged the issue only recently, saying it was indeed due to a software bug.
“We apologize to any customer who has experienced less than optimal performance on their new systems,” the company said.
Apple claimed the issue never occurred during in its testing. However, after a video from Dave Lee, the company was able to replicate the issue with further testing. An Apple representative told The Verge that the issue comes up only in fairly specific, highly intense workloads, and this was why it wasn’t able to catch the issue before the device’s release. The thermal throttling issue impacts all the new MacBook Pros — both the 13-inch and 15-inch — and all the Intel processor configurations.
“Following extensive performance testing under numerous workloads, we’ve identified that there is a missing digital key in the firmware that impacts the thermal management system and could drive clock speeds down under heavy thermal loads on the new MacBook Pro,” Apple said in a statement.
Further, the iPhone maker said after the update, the new 15-inch MacBook Pro will work up to 70% faster, while the smaller version with Touch Bar will be up to two times faster. The company shared no further details on the “missing digital key” except for the fact that it impacts the thermal management system.