Panic - Watchdog Timeout: no checkins from watchdogd in 185 seconds

As a follow up, this was fixed for me with the August 12 10.15.6 supplemental update, as mentioned here https://www.macrumors.com/2020/08/12/apple-releases-macos-10-16-5-supplemental-update/. Note that this update is different from just '10.15.6'... it seems Apple doesn't like to increment minor numbers and is still calling this 10.15.6 supplement update.

I spent a long time with Apple support looking at dumps from the panics on my machine - they found nothing useful.

However, their advice worked. I installed a completely new system on an external drive, and recreated the users - not copying them from previous backups. I've only copied over applications as I've needed them specifically.

I've now not had any panics for over two months. They were occurring twice a day. So, I don't know what third party was causing the problem, but that was what was the ætiology.

After hours in the phone with Apple and a drop off at the Apple store, they concluded it was either a faulty logic board or solid state drive. Both were replaced and the problem stopped. I was glad to have a backup in Time Machine from just before the computer failed.

I unchecked the following on my System preferences, Energy Saver, Battery options

1. Prevent computer from sleeping automatically when the display is off
2. Enable Power Nap while plugged into a power adapter

This has led to two overnight sessions of no kernel panics so far. Hope this helps someone

instanton wrote:

On my Mac Pro, it was being caused by the McAfee kext mandated by my employer. Started in safe mode, rock solid for three weeks. Started with McAfee, crash within a few hours. Has been up continuously since I was allowed to get rid of McAFee going on three weeks now with pretty close to 100% CPU utilization during that time. Just FYI.

If you have McAfee 10.6.6, you can put it into kext-less mode, which has helped at my employer (same mandate for company Macs)

https://docs.mcafee.com/bundle/endpoint-security-10.6.0-installation-guide-macOS/page/GUID-74D9510B-A542-4811-AF36-78EA5949128A.html

This problem has gone off the boil generally with latest macOS updates, (to Big Sur where possible) removing all security and cleaner apps and avoiding USB hubs. Have you gone through the previous pages?

Backup.

Go to https://support.apple.com/downloads/macos and look for 10.15.4 COMBO update.

Download and run it.

Also some types of External monitors still cause kernel panics.

Thanks, in my case the problem has been solved by disabling McAfee Endpoint Security for Mac, 10.6.6(105).

Running in safe mode, the watchdog kernel panics go away and my Mac Pro has been up for three days. So now there's the tedious work of figuring out which kext is the cause.

This 100% fixed my issue. Not sure if I would _personally_ classify CleanMyMac as Malware, but removing it fixed my issue right away.

Well, it really shouldn’t have worked, because a normal update should work. However, I have done this, and I have now not had a panic for some weeks, when they were happening every day:

Go to https://support.apple.com/downloads/macos and look for 10.15.4 COMBO update.

so, before you take your machine to be repaired, try the update with the COMBO, and it really might work.

This must mean that there’s a subtle error in the standard update process.

let’s hope Apple is reading this and fixes it.

Thanks to @dragontorc, he clued me in that "there are numerous reports from many users for kernel panics caused by a memory leak associated with a bug on the App Sandbox. VMWare and VirtualBox had already identified the issue."

and

"Apparently Apple is aware of the bug and I suppose a supplemental update containing a fix is currently in the works."

In my case I use VMWare Fusion...

https://discussions.apple.com/thread/251618187?answerId=253158745022#253158745022

I had lots of these kernel panic error in my iMac 21.5 inch 2017 running Catalina 10.15.7. So. So, I started a very long process: disconnect every peripheral; low level format of the internal disk; fresh OS (+update) and relevant apps installation from network; restore of only documents and data form TimeMachine backup; peripherals connected; all, with frequent shutdowns to check for the problem arising again. It didn´t show up.

Then, I got an error and decided to format the TimeMachine disk just in case. After a fresh full backup, the error showed up again; this time I noticed that the TimeMachine disk was "growling" a lot after the shutdown command and I got the restart and the kernel panic error.

My easy fix: I just eject the TimeMachine disk before shutdown, and everything goes well. I also have an external monitor that doen´t seem to matter to my process.

Hope it helps someone until Apple finds a way out.

I can confirm that, in my case, the culprit looks like ClamXav. I already did half a dozen shutdowns and restarts in conditions I knew would trigger a kernel panic, and I'm glad to say that it's gone. Hope it helps someone.

I posted in this thread earlier. My problem with this crash turned out to be hardware. It resolved after replacement of the logic board and solid state drive. The problem started while I was working in Lightroom CC Classic with a spinning beachball that I couldn't clear without a restart.

I don't know what LR could have done to break hardware and I would guess this is just coincidence.

But it's an odd coincidence...