Crash when switching between full screen VM's

[dwangoac]

Issue report requested by Discord user osy:

UTM crashed while I was quickly switching between different fullscreen VM's and other full-screen applications. I've attached the crash log below. I have not yet been able to reproduce the issue (Edit: I've reproduced it twice more, once with only a single gesture from the desktop to a fullscreen UTM running an Apple virtualization stack) and I did not have debug logging enabled at the time of the crash.

Configuration

• UTM Version: 4.0.9 (68)
• macOS Version: macOS 13.0 (22A380)
• Mac Chip (Intel, M1, ...): M1 Max

Crash log
Attached: UTM-2022-10-27-181934.ips.zip

[osy]

Thread 7 Crashed::  Dispatch queue: com.apple.virtualization.spice-agent
0   libobjc.A.dylib                        0x19bcb5820 objc_msgSend + 32
1   AppKit                                 0x19f407fac -[NSPasteboard _updateTypeCacheIfNeeded] + 640
2   AppKit                                 0x19f407c70 -[NSPasteboard _typesAtIndex:combinesItems:] + 36
3   Virtualization                         0x2030f887c -[VZSpiceAgent _sendClipboardGrab:] + 264
4   Virtualization                         0x2030f84d8 -[VZSpiceAgent _checkChangeCount:withPauseCount:] + 396
5   Virtualization                         0x2030f8c30 void Base::DispatchQueue::after<-[VZSpiceAgent _checkChangeCount:withPauseCount:]::$_4>(std::__1::chrono::duration<long long, std::__1::ratio<1l, 1000000000l> >, -[VZSpiceAgent _checkChangeCount:withPauseCount:]::$_4&&)::'lambda'(void*)::__invoke(void*) + 36
6   libdispatch.dylib                      0x19be9b504 _dispatch_client_callout + 20
7   libdispatch.dylib                      0x19be9e994 _dispatch_continuation_pop + 504
8   libdispatch.dylib                      0x19beb1fa0 _dispatch_source_invoke + 1588
9   libdispatch.dylib                      0x19bea2a94 _dispatch_lane_serial_drain + 376
10  libdispatch.dylib                      0x19bea373c _dispatch_lane_invoke + 436
11  libdispatch.dylib                      0x19beae34c _dispatch_workloop_worker_thread + 652
12  libsystem_pthread.dylib                0x19c01e100 _pthread_wqthread + 288
13  libsystem_pthread.dylib                0x19c01ce20 start_wqthread + 8

Crash is in Apple's Virtualization code. Reported with Apple: FB11736021

[dwangoac]

I've encountered the issue two additional times (and reported to Apple). In one instance, UTM was fullscreen and I was using a three finger swipe from my desktop to access it, rather than rapidly switching in any way. In other words, this appears to be related to switching to a full-screen VM running under Apple virtualization.

[dwangoac]

Update: I had another reoccurrence, but this time I was moving my mouse into the region of a windowed VM when the crash occurred. I used the crash handler report feature to send it to Apple.