Getting these build errors building with Xcode 13 beta 4 on an Intel Mac.

I'm not on macOS 12 locally but it should at least build (so I can run it on my M1 with macOS 12), so not sure what's going on?

Unlike the macOS VM stuff, VZMacGraphicsDisplayConfiguration seems to be available on x86_64, so it's possible that it might work to attach a display to a Linux VM.

I was already on the fence about supporting the Linux and macOS codepaths, especially as it became clear that there is limited overlap in Virtualization.framework featureset between the two platforms.

Then, although it probably wasn't his intention, @mxswd put the nail in the coffin by posing this question about when—if ever—a virtualized Linux VM would be superior to Docker. 😜 I think the answer is pretty conclusively "no," so let's just update Microverse accordingly.

Thread 34 Queue : com.metacognitive.Microverse.VirtualMachineController (serial)
#0	0x00000001c3aa81f8 in dispatch thunk of AnySubscriberBase.receive(_:) ()
#1	0x00000001c6081a40 in closure #1 in NSObject.KVOSubscription.init<τ_0_0>(_:_:_:_:) ()
#2	0x00000001c6082e38 in partial apply for thunk for @escaping @callee_guaranteed (@guaranteed τ_0_0, @in_guaranteed NSKeyValueObservedChange<τ_0_1>) -> () ()
#3	0x00000001c60337b0 in closure #1 in _KeyValueCodingAndObserving.observe<τ_0_0>(_:options:changeHandler:) ()
#4	0x00000001c6033430 in specialized NSKeyValueObservation.Helper._swizzle_me_observeValue(forKeyPath:of:change:context:) ()
#5	0x00000001c6084180 in @objc NSKeyValueObservation.Helper._swizzle_me_observeValue(forKeyPath:of:change:context:) ()
#6	0x00000001b56a95dc in NSKeyValueNotifyObserver ()
#7	0x00000001b5775de0 in NSKeyValueDidChange ()
#8	0x00000001b5828b90 in NSKeyValueDidChangeWithPerThreadPendingNotifications ()
#9	0x00000001b482ae60 in __NSARRAY_IS_CALLING_OUT_TO_A_BLOCK__ ()
#10	0x00000001b482ae0c in -[__NSArrayM enumerateObjectsWithOptions:usingBlock:] ()
#11	0x00000001b56c61b4 in -[NSProgress _setValueForKeys:settingBlock:] ()
#12	0x00000001b56cb55c in -[NSProgress setCompletedUnitCount:] ()
#13	0x00000002180fee18 in void Base::DispatchQueue::async<-[VZMacOSInstaller reportProgress:]::$_3>(-[VZMacOSInstaller reportProgress:]::$_3&&)::'lambda'(void*)::__invoke(void*) ()
#14	0x0000000100b89e48 in _dispatch_client_callout ()
#15	0x0000000100b93168 in _dispatch_lane_serial_drain ()
#16	0x0000000100b9421c in _dispatch_lane_invoke ()
#17	0x0000000100ba3b04 in _dispatch_workloop_worker_thread ()
#18	0x0000000100aabfdc in _pthread_wqthread ()
Enqueued from com.apple.virtualization.installer-messenger (Thread 32) Queue : com.apple.virtualization.installer-messenger (serial)
#0	0x0000000100b8f538 in dispatch_async_f ()
#1	0x00000002180f7614 in VzInstallation::InstallerMessenger::handle_send_progress(unsigned int) ()
#2	0x00000002180f7300 in std::__1::__function::__func<VzShared::Messenger::Handler::Handler<VzInstallation::InstallerMessenger, unsigned int>(VzInstallation::InstallerMessenger&, void (VzInstallation::InstallerMessenger::*)(unsigned int))::'lambda'(Base::Xpc::Dictionary const&, Base::Xpc::Object), std::__1::allocator<VzShared::Messenger::Handler::Handler<VzInstallation::InstallerMessenger, unsigned int>(VzInstallation::InstallerMessenger&, void (VzInstallation::InstallerMessenger::*)(unsigned int))::'lambda'(Base::Xpc::Dictionary const&, Base::Xpc::Object)>, bool (Base::Xpc::Dictionary const&, Base::Xpc::Object)>::operator()(Base::Xpc::Dictionary const&, Base::Xpc::Object&&) ()
#3	0x00000002180ab604 in VzShared::Messenger::dispatch(Base::Xpc::Dictionary const&) ()
#4	0x00000002180f65a8 in invocation function for block in VzInstallation::InstallerMessenger::InstallerMessenger() ()
#5	0x00000001b44bf1e8 in _xpc_connection_call_event_handler ()
#6	0x00000001b44bdc08 in _xpc_connection_mach_event ()
#7	0x0000000100b89f08 in _dispatch_client_callout4 ()
#8	0x0000000100bada7c in _dispatch_mach_msg_invoke ()
#9	0x0000000100b92f0c in _dispatch_lane_serial_drain ()
#10	0x0000000100baf23c in _dispatch_mach_invoke ()
#11	0x0000000100b92f0c in _dispatch_lane_serial_drain ()
#12	0x0000000100b9421c in _dispatch_lane_invoke ()
#13	0x0000000100ba3b04 in _dispatch_workloop_worker_thread ()
#14	0x0000000100aabfdc in _pthread_wqthread ()
#15	0x0000000100ab3c78 in start_wqthread ()

In theory, this adds support for sharing filesystems into a macOS guest. Unfortunately, I can't get mount_9p to work within the VM no matter what I do—so, parking this here for now.

Resolves #13.

Project builds and runs successfully, but IDE integration complains about a lot of errors. This doesn't affect KhaosT/MacVM, so I'm not sure what I've misconfigured.

I wrote this in a rush and didn't pay enough attention to which callbacks happen in the background vs. the main queue. Audit all asynchrony and make sure it's sane.

Also, we can put VMs onto their own dispatch queue.

Typical cause is always like this. Just different OpenGl, Metal errors for different apps.

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000000
Exception Codes: 0x0000000000000001, 0x0000000000000000
VM Region Info: 0 is not in any region.  Bytes before following region: 4329668608
      REGION TYPE                    START - END         [ VSIZE] PRT/MAX SHRMOD  REGION DETAIL
      UNUSED SPACE AT START
--->  
      __TEXT                      102118000-102a70000    [ 9568K] r-x/r-x SM=COW  ...etryDashWorld
Exception Note:  EXC_CORPSE_NOTIFY
Termination Reason: SIGNAL 11 Segmentation fault: 11
Terminating Process: exc handler [529]

Triggered by Thread:  0

Thread 0 Crashed::  Dispatch queue: com.apple.main-thread
0   CoreFoundation                	       0x1be3a17bc CFStringGetLength + 8
1   libGFXShared.dylib            	       0x23bd68a04 gfxInitializeLibrary + 720
2   GLEngine                      	       0x23bf23b8c gliInitializeLibrary + 68
3   OpenGLES                      	       0x23bf1f784 eagl_init + 480
4   OpenGLES                      	       0x23bf1f340 -[EAGLSharegroup initWithAPI:sharedWithCompute:] + 228
5   OpenGLES                      	       0x23bf1e46c -[EAGLContext commonInitWithAPI:properties:] + 208
6   OpenGLES                      	       0x23bf1e2c8 -[EAGLContext initWithAPI:properties:] + 268

I suppose it is because wrong gpu config, though as I can see Virtualization.framework doesn't contains any public method for video card config. I'd tried to disable SIP of VM and set gpu NVRAM boot args but no any effect.

-(id)init {
    if ([[self className] containsString:@ "_VZVirtualMachineStartOptions"]) {
        NSLog(@"Found %@", [self className]);
        bootLoader = self;
        [self hook_setBootMacOSRecovery:0];
    }
    return self;
}

+(void)load
{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        [objc_getClass("_VZVirtualMachineStartOptions") swizzleInstanceMethod:@selector(setBootMacOSRecovery:) withMethod:@selector(hook_setBootMacOSRecovery:)];
    });
}

- (void) hook_setBootMacOSRecovery: (int) boot {
    printf("hooked");
    [self hook_setBootMacOSRecovery:1];
}

It's probably reasonable to trash the VM if an installation is aborted mid-way through, but it should at least not crash the app. (Especially annoying with document restoration at startup.)