After Upgrade to 12.4, 2017 21" iMac Has Frequent Restarts

[Buadhai]

After installing the 12.4 update my 2017 21" iMac has been restarting at least once a day. I'm never there when this happens. On Thursday it rebooted four times in rapid succession.

I'm not smart enough to understand Diagnostic Report files, but here a few lines from the most recent one that might give a hint:

mp_kdp_enter() timed-out during locked wait after NMI;expected 4 acks but received 1 after 9777577 loops in 1704000001 ticks
panic(cpu 0 caller 0xffffff8006bd19d7): Machine Check at 0x00007ff818b323d7, registers

Panicked task 0xffffff8b717d19f0: 8 threads: pid 1127: StocksWidget
Backtrace (CPU 0), panicked thread: 0xffffff8b713fdaa0, Frame : Return Address

The StocksWidget is mentioned several time. The entire Diagnostic Report is here (PasteBin) in case anyone wants to accept what to me seems like an impossible challenge.

Anyone else experiencing this?

[Aside: I have to wonder if the StocksWidget is as panicked about the market as I am.)

 

[Synchro]

I'm seeing a similar thing with an M1 Mini – spontaneous reboots several times a day, though it started doing it with 12.3; 12.4 has not improved it.

 

[Buadhai]

I have read elsewhere that some adapters (USB-C -> HDMI) can cause kernel panics. I have temporarily removed my external monitor and adapter from my iMac to see if that eliminates the problem. I don't know how you purchase an adapter that works other than by trial and error.

Looking back on older panic reports I find that mine also started with 12.3.

 

[Buadhai]

It turns out it wasn't the adapter or monitor. After removing both two days ago I had another kernel panic this afternoon.

Back to the drawing board. I'm now removing an Orico USB hub.

 

[Buadhai]

It wasn’t the USB hub either. Now I’m reinstalling Monterey from recovery mode.

 

[Buadhai]

Two and a half months later I still haven't solved this. If you want to see all the stuff that didn't work, look here:

Is It Worth Repairing a 2017 iMac With Frequent, Irritating and Undiagnosable Kernel Panics?