Notebookcheck Logo

Apple T2 chip causing kernel panics in few 2018 MacBook Pros and iMac Pros

BridgeOS in the Apple T2 chip is causing some instances of kernel panics in the iMac Pro and MacBook Pro. (Source: Digital Trends)
BridgeOS in the Apple T2 chip is causing some instances of kernel panics in the iMac Pro and MacBook Pro. (Source: Digital Trends)
Owners of the iMac Pro and the new 2018 MacBook Pro have turned to Apple forums to report several instances of kernel panics, which trace back to BridgeOS found in the Apple T2 chip. The T2 chip provides support for secure boot, encrypted storage, and the always-on 'Hey Siri' command. Apple is apparently aware but has not publicly acknowledged the issue so an estimated date for a fix is not yet known.

There have been a few instances of kernel panics in the iMac Pro being reported in the Apple Community forums but now, similar instances are being reported for the 2018 MacBook Pro with Touch Bar as well. Both the cases of kernel panics seem to indicate some issue with the BridgeOS. For those not aware, BridgeOS is the firmware used in the Apple T2 chip found in the new iMac Pro and the 2018 MacBook Pro with Touch Bar. The T2 chip is an isolated enclave that provides secure boot functions, SSD encryption, and responds to commands such as 'Hey Siri'. A user krypttic on the Apple Community forums wrote,

You iMac Pro folks should throw a welcome party for all of us new 2018 MacBook Pro users.  These new laptops also have the new T2 chips and guess what?  The same Bridge OS crashes that you are seeing.

My machine was fresh from the factory and I reinstalled everything rather than using Migration Assistant to avoid the "your old stuff caused it to crash" excuse.  My computer has rebooted while sleeping twice in three days with the "your Mac restarted because of a problem" screen.

 I just dropped $4800 on this thing.  Inexcusable..."

Examining the posts in the Apple Community forums reveals varied reasons for the BridgeOS kernel panic — from waking up to sleep with no peripherals attached to daisy chaining devices via the Thunderbolt 3 ports. This particular kernel panic does not seem to be documented in Apple's troubleshooting guides and affected customers were either asked to do a clean install of the OS or swap their hardware for a replacement. Installing the supplemental update that was released yesterday to address the throttling issues had mixed results. But apparently, the problem still persists. 

Digital Trends, which first reported this story said that there are a few other suggestions to temporarily mitigate the error including disabling FileVault and Power Nap or stop daisy-chaining devices, not using a Thunderbolt 3 to Thunderbolt 2 connector, turning off Secure Boot, not locking the device with an Apple Watch, removing third-party kexts etc. 

So what can you do? Simple. Turn off your Mac and wait for Apple to acknowledge and come up with a fix. But seriously, although Apple is yet to publicly acknowledge this issue, if you have ever encountered errors with BridgeOS, try minimizing the number of daisy-chained devices or stopping the computer from entering sleep mode. The issue doesn't seem to be as prevalent as the CPU throttling issue that grabbed headlines till yesterday so it might be some time before Apple can collect enough diagnostic logs to make sense of what's going on.Better still, approach the nearest Apple Authorized Service Center and get it examined. In all probability, you might end up with a replacement.

Are you facing BridgeOS kernel panics as well? Let us know in the comments below.


Read all 1 comments / answer
static version load dynamic
Loading Comments
Comment on this article
Please share our article, every link counts!
> Expert Reviews and News on Laptops, Smartphones and Tech Innovations > News > News Archive > Newsarchive 2018 07 > Apple T2 chip causing kernel panics in few 2018 MacBook Pros and iMac Pros
Vaidyanathan Subramaniam, 2018-07-27 (Update: 2018-07-27)