What does this mean? (x86 global reset detected)

What does this mean? (x86 global reset detected) Recently my iMac Pro would not turn on after the christmas break. The only way I could get it to eventually restart was to reset the SMC. Even after disconnecting every plugin and resetting the SMC it took about half a dozen 10 second presses of the power button to get it going. Once restarted I removed everything from login items, shut it down and tried again. Nothing, it wouldn't restart again. When I eventually restarted it, I set it to restart... this was perfect no issues whatsoever. Generally I never switch off my Mac, so I don't know how long this has been going on. I am a designer and run with a lot of fonts which have been known to cause issues over the years. All software is up to date, (macOS Sonoma) and other than this issue my Mac is clean and runs perfectly. I'm mystified.

panic(cpu 1 caller 0xfffffff018d72f60): x86 global reset detected

Debugger message: panic

Memory ID: 0x6

OS release type: User

OS version: 21P2057

macOS version: Not set

Kernel version: Darwin Kernel Version 23.2.0: Wed Nov 15 21:09:28 PST 2023; root:xnu-10002.61.3~1/RELEASE_ARM64_T8010

KernelCache UUID: 4CC579D0A7E4659D1724E6DFE3E8CCEF

Kernel UUID: 1D1BC1F4-12F1-3532-B69F-61F6683CEB7C

Boot session UUID: 988B17D1-6D19-4C88-889C-06BFFF4A6B21

iBoot version: iBoot-10151.61.4

secure boot?: YES

roots installed: 0

x86 EFI Boot State: 0x2

x86 System State: 0x0

x86 Power State: 0x0

x86 Shutdown Cause: 0xf5

x86 Previous Power Transitions: 0x70707060400

PCIeUp link state: 0x8927160e

macOS kernel slide: not available

Paniclog version: 14

Kernel slide: 0x00000000129c0000

Kernel text base: 0xfffffff0199c4000

mach_absolute_time: 0x243bc790

Epoch Time: sec usec

Boot : 0x65a69852 0x000f1366

Sleep : 0x65a69863 0x00003dc2

Wake : 0x65a69a10 0x0007000d

Calendar: 0x65a69a15 0x000b71fc

Zone info:

Zone map: 0xffffffdc12cd4000 - 0xffffffe212cd4000

. VM : 0xffffffdc12cd4000 - 0xffffffdcf9338000

. RO : 0xffffffdcf9338000 - 0xffffffdd46004000

. GEN0 : 0xffffffdd46004000 - 0xffffffde2c668000

. GEN1 : 0xffffffde2c668000 - 0xffffffdf12ccc000

. GEN2 : 0xffffffdf12ccc000 - 0xffffffdff9334000

. GEN3 : 0xffffffdff9334000 - 0xffffffe0df99c000

. DATA : 0xffffffe0df99c000 - 0xffffffe212cd4000

Metadata: 0xffffffeffc624000 - 0xffffffeffde24000

Bitmaps : 0xffffffeffde24000 - 0xffffffeffdf48000

Extra : 0 - 0

TPIDRx_ELy = {1: 0xffffffdf133ade18 0: 0x0000000000000001 0ro: 0x0000000000000000 }

CORE 0: PC=0xfffffff019bef008, LR=0xfffffff019bef008, FP=0xffffffeff05fbef0

CORE 1 is the one that panicked. Check the full backtrace for details.

Compressor Info: 0% of compressed pages limit (OK) and 0% of segments limit (OK) with 0 swapfiles and OK swap space

Panicked task 0xffffffe0df911ff0: 0 pages, 187 threads: pid 0: kernel_task

Panicked thread: 0xffffffdf133ade18, backtrace: 0xffffffeff06736a0, tid: 964

lr: 0xfffffff019bbea90 fp: 0xffffffeff0673710

lr: 0xfffffff019ced07c fp: 0xffffffeff0673780

lr: 0xfffffff019cec0b0 fp: 0xffffffeff06738a0

lr: 0xfffffff019b81630 fp: 0xffffffeff06738b0

lr: 0xfffffff019bbe4cc fp: 0xffffffeff0673c60

lr: 0xfffffff01a23cc58 fp: 0xffffffeff0673c80

lr: 0xfffffff018d72f60 fp: 0xffffffeff0673cb0

lr: 0xfffffff018d59f40 fp: 0xffffffeff0673d10

lr: 0xfffffff018d60908 fp: 0xffffffeff0673d60

lr: 0xfffffff018d5a978 fp: 0xffffffeff0673e00

lr: 0xfffffff018d597d0 fp: 0xffffffeff0673e30

lr: 0xfffffff019c14034 fp: 0xffffffeff0673f20

lr: 0xfffffff019b8c6c4 fp: 0x0000000000000000