Big Sur panic when connect/disconnect usb-c dock

System: MacBook Pro (16-inch, 2019)

OS Version: Big Sur 11.5

Graphics: AMD Radeon Pro 5300M 4 GB, Intel UHD Graphics 630 1536 MB

Problem persists on Big Sur 11.5 update. When I connect to external monitor, MacBook Pro crashes. Has been months now of device crashing when connecting to external monitor. Ridiculous.

System: MacBook Pro (16-inc, 2019) OS Version: Big Sure 11.5 Graphics: Intel UHD Graphics 630 and AMD Radeon Pro 5300M

Same issue as above. Plugging in an HDMI or DisplayPort external monitor results in the system crashing and rebooting. This did NOT occur on this system on Catalina but as soon as I upgraded to 11.4 it started happening.

Kernel panic in my case has nothing to do with peripherals. Instead it happens anytime my laptop goes to sleep. It is an extremely troubling bug as, again, it has NOTHING to do with 3rd party hardware/software/connectors in my case.

It began when I updated to Big Sur 11.5 several days ago. Rebooting and complete shutdown does not help:

Hardware Overview:

 Model Name: MacBook Pro  Model Identifier: MacBookPro13,3  Processor Name: Quad-Core Intel Core i7  Processor Speed: 2.9 GHz  Number of Processors: 1  Total Number of Cores: 4  L2 Cache (per Core): 256 KB  L3 Cache: 8 MB  Hyper-Threading Technology: Enabled  Memory: 16 GB  System Firmware Version: 429.140.8.0.0  SMC Version (system): 2.38f1

Just updated to the 11.5.1 update today and it did not fix my issue either. I reported this issue to apple about a week ago and they suggested backing up and doing a fresh install. I am getting panics when I connect to my cal digit usb c thunderbolt dock. my dock is display port and I'm using adapters cause the 6monitors I have are hdmi(I bought the display port one without realizing there was an hdmi option) I can connect for a bout 2 or 3 min. then it panics and restarts. I will try the fresh install method in a few days when I have the time and update with the status of that potential fix. oh forgot to mention I'm on a 2019 16 Mac book pro with i9 32gig ram 2tb storage, and radeon 5500m 8gb model. if anyone can help I would appreciate it.

Just an additional point on the graph.

I have the issue (with my pluggable TB3 dock) far, far less now my monitors are on HDMI vs DP. Although I did get it once every so ofter, mainly after waking my machine up.

However, since unplugging a powered USB hub that I had plugged into the TB3 dock (by powered, I mean it has it's own power adapter) I have had zero issues. All the same peripherals are plugged in via an alternative dock (both are just regular USB 3.0 docks, nothing fancy) and all is well. So far 🤞🏻

I have now been added to this problem... My company is pushing everyone with a Mac to upgrade to Big Sur and now my machine crashes every other time I connect or disconnect my CalDigit USB-C Pro dock. I have two ASUS displays connected with DisplayPort.

I downloaded the latest Hub Support driver from CalDigit but that didn't change anything.

This is very frustrating especially with not having the ability to go back to Catallina.

I somehow feel it could have something to do with HDCP. I also have that issue with my HP G2 Dock. Not only does it crash the machine, but regularly starts to stutter on the external screen (once every few seconds). If you then look into log console you will find lots of lines about stalled HDCP actions that come exactly when the stutter occurs. The latest firmware update of the G2 dock did indeed brought some HDCP fixes (mostly for HDCP 1.4 <> 2.2 switching).

For now, I just connected the Monitor to the Thunderbolt downstream port on the G2 (which bypasses the DP Hub in the Dock) and have no such issues. There must be some problem with those DisplayPort Hubs and macOS. On Bootcamp there are no problems, but Windows also doesn't HDCP encypts your content if there's not reason for it. macOS does all the time if the devices support HDCP.

I was able to get around the problem by connecting to the monitor via a USB-C to DisplayPort cable, so it doesn't use the USB Hub to transmit image data. Not the best solution, but I was able to use all the other peripherals (keyboard, mouse, Ethernet) along with the 4k monitor.

It's so annoying. I have the exact same setup at home as well at the office. The only exception is, that my two Lenovo ThinkVision P24h-10 monitors at the office are the newer 75Hz variant. At home I have absolutely no problem. At the office my MacBook Pro 16" (AMD Radeon Pro 5300M 4 GB) crashes all the time. Exact same pattern as everyone here. I plug in the monitors wake up my MacBook… woosh… Fans spins — Kernel Panic.

Happens since 11.13. It's nice that the problem is fixed in 12 Beta but I need this machine for work so beta software is pretty much non acceptable.

OK im not sure if this applies to anyone here however cal digit has a driver support package listed in library/extensions. I found an older post about it causing issues on a different version of Mac OS from last year. I moved that .kext file to trash and I have stopped having the issue. I hope this helps those with this problem. This is for the cal digit dock only. if you are having this issue with a different dock then you may want to look into the driver support for that dock.

I’ve unfortunately been experiencing this as well. Plugable, the creator of the dock I’m using, posted about the issue and a possible workaround until Apple fixes the issue.

https://kb.plugable.com/thunderbolt-3-docks/kernel-panic-when-connecting-the-dock-to-my-macbook-pro-16

The workaround they suggested is to unplug HDMI displays before you plug the thunderbolt cable into the laptop and then plug the displays back in. haven’t tested this out yet but thought I would share.

The lack of acknowledgement from Apple in this regard is mind boggling, with it clearly happening in a variety of combinations with external hardware, both through hubs/docks or displays with integrated hubs - in my case with a CalDigit USB-C Pro dock (using Thunderbolt 3) or random LG and Dell monitors directly.

For CalDigit users, I'm also a bit baffled that their support seems to still tell people they're unaware (reading other comments), since they have this knowledge base article up since January 2021: https://www.caldigit.com/my-intel-based-mac-crashes-when-un-docking-or-re-docking/

I've been trying the workaround suggested in there of waiting for a couple seconds between unplug and re-plug before/after going to sleep, which anecdotally seems to have reduced the number of kernel panics for me.

Hello everyone!

Same problem using Allure by eSTUFF USB C hub (100W). I'm using a display port with my LG monitor. Sometimes, probably when I plug in the station (probably) before waking up my a2141 model (taking it from home to office), the monitor won't display anything. When I try to reconnect the monitor, the system hangs and the kernel panic is visible.

I was pretty sure, that most of the panic information was related to the AMD graphics card - it has a sense for me because it's related to displaying the graphic on the monitor. Problem is, that the signal must be converted from USB C to DP. Hub in description is quite fine, I had a lot of single wired hubs, and when I plug-in monitor, all other devices hang after a while, and the hub was so hot that you can't touch it. This version promises, that they use a separate processor for each port, so it's not a problem with this device itself. Apple - please revise the driver, there must be something common in all those problems we present here!

@matthiaswenz - are you suggesting plugging the dock after wake up or before?

Same problem here, MacBook Pro (16-inch, 2019) with CalDigit TS3 Plus, two 4k samsung screen.

I have the same recurring problem as well. About 1 to 2 times per week will get a kernel panic. This happens on wake from sleep.

Mac OS 11.5.1. MacBook Pro 16 inch 2019. System Firmware Version: 1554.140.20.0.0 (iBridge: 18.16.14759.0.1,0)

Using a WAVLINK Thunderbolt 3 Display Docking station. Model UTD21 REV B.

I power the laptop from that docking station through the USB-C port and have 2x 4k LG monitors connected on the rear of that using Display port.

panic(cpu 3 caller 0xffffff800929fc36): [kext.kalloc.2048]: element modified after free (off:1584, val:0x0000210100000000, sz:2048, ptr:0xffffff93ce3b3000, prot:zero)
 1584: 0x0000210100000000
 1592: 0x0000000b00005400
 1600: 0x0000000000000009
 1608: 0x0000020300000100
 1616: 0x0000015400000154
 1624: 0x0000001000000a00
 1632: 0x000008340000041a
 1640: 0x0000000000001400
Backtrace (CPU 3), Frame : Return Address
0xffffffa1be712d00 : 0xffffff8008a8e04d 
0xffffffa1be712d50 : 0xffffff8008bd4e13 
0xffffffa1be712d90 : 0xffffff8008bc540a 
0xffffffa1be712de0 : 0xffffff8008a32a2f 
0xffffffa1be712e00 : 0xffffff8008a8d86d 
0xffffffa1be712f20 : 0xffffff8008a8db63 
0xffffffa1be712f90 : 0xffffff800929dc0a 
0xffffffa1be713000 : 0xffffff800929fc36 
0xffffffa1be713480 : 0xffffff8008aec9e6 
0xffffffa1be7134f0 : 0xffffff8008a9d65c 
0xffffffa1be713540 : 0xffffff80091ae872 
0xffffffa1be713560 : 0xffffff800bb5d944 
0xffffffa1be713580 : 0xffffff800bb6bb08 
0xffffffa1be7135e0 : 0xffffff800bb5e096 
0xffffffa1be713680 : 0xffffff800bb6020f 
0xffffffa1be713930 : 0xffffff800bb5e59b 
0xffffffa1be713a90 : 0xffffff800bb5389f 
0xffffffa1be713af0 : 0xffffff800bb583b0 
0xffffffa1be713cb0 : 0xffffff800928575e 
0xffffffa1be713d00 : 0xffffff8008d487af 
0xffffffa1be713e10 : 0xffffff8008d3dd41 
0xffffffa1be713f40 : 0xffffff800914001e 
0xffffffa1be713fa0 : 0xffffff8008a331f6 
      Kernel Extensions in backtrace:
         com.apple.security.sandbox(300.0)[305D7379-15AF-36C7-A23A-F8E16A52132C]@0xffffff800bb4c000->0xffffff800bb92fff
            dependency: com.apple.driver.AppleMobileFileIntegrity(1.0.5)[152D7047-0D43-3CA8-B1EA-251D3F80AC28]@0xffffff800a0c0000->0xffffff800a0d5fff
            dependency: com.apple.iokit.IOStorageFamily(2.1)[6CD2A6EC-9FFC-370D-8FEE-C8016E5C6BBA]@0xffffff800b66f000->0xffffff800b680fff
            dependency: com.apple.kext.AppleMatch(1.0.0d1)[B81FB839-709B-3BF8-87E6-640E9505A162]@0xffffff800a0bc000->0xffffff800a0befff

Process name corresponding to current thread: installd
Boot args: chunklist-security-epoch=0 -chunklist-no-rev2-dev

Mac OS version:
20G80

Kernel version:
Darwin Kernel Version 20.6.0: Wed Jun 23 00:26:31 PDT 2021; root:xnu-7195.141.2~5/RELEASE_X86_64