How to resolve mojo instance registration error

[Marshall Greenblatt]

Hi All,

I'm in the process of updating my Chromium-based application to master revision 0bfd25d4 (#381305) and I'm seeing this new error message on OS X (10.11.1 building with Xcode 7.1) [1]:

[0317/123919:ERROR:shell.cc(293)] Error: Instance: exe:chrome attempting to register an instance for a process it created for target: exe:chrome_renderer without the mojo:shell{client_process} capability class.

Can anyone shed some light on what this error means and how I might go about resolving it?

Thanks,

Marshall

[1] Full call stack for the error message:

* thread #1: tid = 0x4d6a, 0x000000010c0275be Chromium Embedded Framework`mojo::shell::Shell::Instance::ValidateClientProcessConnection(this=0x000000012145bdc0, client_process_connection=0x00007fff5fbfbb98, target=0x00007fff5fbfba30, callback=0x00007fff5fbfbbf0)> const&) + 334 at shell.cc:293, name = 'CrBrowserMain', queue = 'com.apple.main-thread', stop reason = breakpoint 2.1

  * frame #0: 0x000000010c0275be Chromium Embedded Framework`mojo::shell::Shell::Instance::ValidateClientProcessConnection(this=0x000000012145bdc0, client_process_connection=0x00007fff5fbfbb98, target=0x00007fff5fbfba30, callback=0x00007fff5fbfbbf0)> const&) + 334 at shell.cc:293

    frame #1: 0x000000010c0205d9 Chromium Embedded Framework`mojo::shell::Shell::Instance::Connect(this=0x000000012145bdc0, target_ptr=<unavailable>, remote_interfaces=mojo::shell::mojom::InterfaceProviderRequest @ 0x00007fff5fbfbbb8, local_interfaces=mojo::shell::mojom::InterfaceProviderPtr @ 0x00007fff5fbfbba0, client_process_connection=mojo::shell::mojom::ClientProcessConnectionPtr @ 0x00007fff5fbfbb98, callback=0x00007fff5fbfbbf0)> const&) + 601 at shell.cc:231

    frame #2: 0x00000001089764b4 Chromium Embedded Framework`mojo::shell::mojom::ConnectorStub::AcceptWithResponder(this=0x000000012145ff58, message=0x00007fff5fbfc9f8, responder=0x00000001214569c0) + 1300 at connector.mojom.cc:1028

    frame #3: 0x000000010464fc2e Chromium Embedded Framework`mojo::internal::Router::HandleMessageInternal(this=0x000000012145cfc0, message=0x00007fff5fbfc9f8) + 286 at router.cc:225

    frame #4: 0x000000010464c1b6 Chromium Embedded Framework`mojo::internal::Router::HandleIncomingMessage(this=0x000000012145cfc0, message=0x00007fff5fbfc9f8) + 1334 at router.cc:187

    frame #5: 0x000000010464bc4f Chromium Embedded Framework`mojo::internal::Router::HandleIncomingMessageThunk::Accept(this=0x000000012145cfc8, message=0x00007fff5fbfc9f8) + 47 at router.cc:81

    frame #6: 0x0000000108976c71 Chromium Embedded Framework`mojo::shell::mojom::ConnectorRequestValidator::Accept(this=0x000000012144a900, message=0x00007fff5fbfc9f8) + 305 at connector.mojom.cc:1059

    frame #7: 0x00000001046379eb Chromium Embedded Framework`mojo::internal::MessageHeaderValidator::Accept(this=0x000000012145a780, message=0x00007fff5fbfc9f8) + 187 at message_header_validator.cc:73

    frame #8: 0x00000001046264a9 Chromium Embedded Framework`mojo::internal::Connector::ReadSingleMessage(this=0x000000012145cff8, read_result=0x00007fff5fbfcb84) + 393 at connector.cc:319

    frame #9: 0x0000000104627c4a Chromium Embedded Framework`mojo::internal::Connector::ReadAllAvailableMessages(this=0x000000012145cff8) + 74 at connector.cc:345

    frame #10: 0x0000000104627b26 Chromium Embedded Framework`mojo::internal::Connector::OnHandleReadyInternal(this=0x000000012145cff8, result=0) + 310 at connector.cc:273

    frame #11: 0x00000001046279c9 Chromium Embedded Framework`mojo::internal::Connector::OnWatcherHandleReady(this=0x000000012145cff8, result=0) + 41 at connector.cc:253

    frame #12: 0x0000000104628b59 Chromium Embedded Framework`void base::internal::RunnableAdapter<void (mojo::internal::Connector::*)(unsigned int)>::Run<unsigned int>(this=0x00007fff5fbfcda8, object=0x000000012145cff8, args=0x00007fff5fbfce64) + 137 at bind_internal.h:181

    frame #13: 0x0000000104628a5d Chromium Embedded Framework`void base::internal::InvokeHelper<false, void, base::internal::RunnableAdapter<void (mojo::internal::Connector::*)(unsigned int)> >::MakeItSo<mojo::internal::Connector*, unsigned int>(runnable=(method_ = 0x00000001046279a0), args=0x00007fff5fbfce10, args=0x00007fff5fbfce64)(unsigned int)>, mojo::internal::Connector*&&, unsigned int&&) + 77 at bind_internal.h:301

    frame #14: 0x00000001046289e3 Chromium Embedded Framework`base::internal::Invoker<base::IndexSequence<0ul>, base::internal::BindState<base::internal::RunnableAdapter<void (mojo::internal::Connector::*)(unsigned int)>, void (mojo::internal::Connector*, unsigned int), base::internal::UnretainedWrapper<mojo::internal::Connector> >, base::internal::InvokeHelper<false, void, base::internal::RunnableAdapter<void (mojo::internal::Connector::*)(unsigned int)> >, void (unsigned int)>::Run(base=0x0000000121444530, unbound_args=0x00007fff5fbfce64) + 131 at bind_internal.h:352

    frame #15: 0x000000010072568e Chromium Embedded Framework`base::Callback<void (unsigned int), (base::internal::CopyMode)1>::Run(this=0x00007fff5fbfcf08, args=0) const + 78 at callback.h:397

    frame #16: 0x0000000104670af7 Chromium Embedded Framework`mojo::Watcher::OnHandleReady(this=0x000000012145d018, result=0) + 599 at watcher.cc:118

    frame #17: 0x0000000104671b29 Chromium Embedded Framework`void base::internal::RunnableAdapter<void (mojo::Watcher::*)(unsigned int)>::Run<unsigned int const&>(this=0x00007fff5fbfd0c8, object=0x000000012145d018, args=0x0000000121444fc0) + 137 at bind_internal.h:181

    frame #18: 0x00000001046719be Chromium Embedded Framework`void base::internal::InvokeHelper<true, void, base::internal::RunnableAdapter<void (mojo::Watcher::*)(unsigned int)> >::MakeItSo<base::WeakPtr<mojo::Watcher>, unsigned int const&>(runnable=(method_ = 0x00000001046708a0), weak_ptr=WeakPtr<mojo::Watcher> @ 0x00007fff5fbfd128, args=0x0000000121444fc0)(unsigned int)>, base::WeakPtr<mojo::Watcher>, unsigned int const&&&) + 94 at bind_internal.h:314

    frame #19: 0x0000000104671934 Chromium Embedded Framework`base::internal::Invoker<base::IndexSequence<0ul, 1ul>, base::internal::BindState<base::internal::RunnableAdapter<void (mojo::Watcher::*)(unsigned int)>, void (mojo::Watcher*, unsigned int), base::WeakPtr<mojo::Watcher>&, unsigned int&>, base::internal::InvokeHelper<true, void, base::internal::RunnableAdapter<void (mojo::Watcher::*)(unsigned int)> >, void ()>::Run(base=0x0000000121444f90) + 148 at bind_internal.h:352

    frame #20: 0x0000000103bc62cf Chromium Embedded Framework`base::Callback<void (), (base::internal::CopyMode)1>::Run(this=0x00007fff5fbfd680) const + 63 at callback.h:397

    frame #21: 0x0000000100b6b7de Chromium Embedded Framework`base::debug::TaskAnnotator::RunTask(this=0x0000000121314e20, queue_function="MessageLoop::PostTask", pending_task=0x00007fff5fbfd668) + 654 at task_annotator.cc:51

    frame #22: 0x0000000100c24700 Chromium Embedded Framework`base::MessageLoop::RunTask(this=0x0000000121314cf0, pending_task=0x00007fff5fbfd668) + 848 at message_loop.cc:470

    frame #23: 0x0000000100c24d36 Chromium Embedded Framework`base::MessageLoop::DeferOrRunPendingTask(this=0x0000000121314cf0, pending_task=0x00007fff5fbfd668) + 86 at message_loop.cc:479

    frame #24: 0x0000000100c25438 Chromium Embedded Framework`base::MessageLoop::DoWork(this=0x0000000121314cf0) + 552 at message_loop.cc:591

    frame #25: 0x0000000100b24c08 Chromium Embedded Framework`base::MessagePumpCFRunLoopBase::RunWork(this=0x00000001213152b0) + 104 at message_pump_mac.mm:330

    frame #26: 0x0000000100b24b7a Chromium Embedded Framework`___ZN4base24MessagePumpCFRunLoopBase13RunWorkSourceEPv_block_invoke(.block_descriptor=<unavailable>) + 42 at message_pump_mac.mm:307

    frame #27: 0x0000000100be7eba Chromium Embedded Framework`base::mac::CallWithEHFrame(void () block_pointer) + 10 at call_with_eh_frame_asm.S:36

    frame #28: 0x0000000100b23f15 Chromium Embedded Framework`base::MessagePumpCFRunLoopBase::RunWorkSource(info=0x00000001213152b0) + 101 at message_pump_mac.mm:306

    frame #29: 0x00007fff907938b1 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17

    frame #30: 0x00007fff907730ac CoreFoundation`__CFRunLoopDoSources0 + 556

    frame #31: 0x00007fff907725cf CoreFoundation`__CFRunLoopRun + 927

    frame #32: 0x00007fff90771fc8 CoreFoundation`CFRunLoopRunSpecific + 296

    frame #33: 0x00007fff90cb2d55 HIToolbox`RunCurrentEventLoopInMode + 235

    frame #34: 0x00007fff90cb2b8f HIToolbox`ReceiveNextEventCommon + 432

    frame #35: 0x00007fff90cb29cf HIToolbox`_BlockUntilNextEventMatchingListInModeWithFilter + 71

    frame #36: 0x00007fff99331d96 AppKit`_DPSNextEvent + 1067

    frame #37: 0x00007fff993311c5 AppKit`-[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454

    frame #38: 0x00007fff99325d28 AppKit`-[NSApplication run] + 682

    frame #39: 0x0000000100b25f78 Chromium Embedded Framework`base::MessagePumpNSApplication::DoRun(this=0x00000001213152b0, delegate=0x0000000121314cf0) + 312 at message_pump_mac.mm:665

    frame #40: 0x0000000100b2481d Chromium Embedded Framework`base::MessagePumpCFRunLoopBase::Run(this=0x00000001213152b0, delegate=0x0000000121314cf0) + 125 at message_pump_mac.mm:238

    frame #41: 0x0000000100c23f4a Chromium Embedded Framework`base::MessageLoop::RunHandler(this=0x0000000121314cf0) + 298 at message_loop.cc:434

    frame #42: 0x0000000100caad95 Chromium Embedded Framework`base::RunLoop::Run(this=0x00007fff5fbff370) + 85 at run_loop.cc:35

    frame #43: 0x0000000100c2197f Chromium Embedded Framework`base::MessageLoop::Run(this=0x0000000121314cf0) + 303 at message_loop.cc:287

    frame #44: 0x00000001006cd4f6 Chromium Embedded Framework`CefBrowserMessageLoop::RunMessageLoop(this=0x0000000121314cf0) + 38 at browser_message_loop.cc:27

    frame #45: 0x00000001006f32e3 Chromium Embedded Framework`CefRunMessageLoop() + 355 at context.cc:205

    frame #46: 0x00000001005382fb Chromium Embedded Framework`::cef_run_message_loop() + 27 at libcef_dll.cc:303

    frame #47: 0x00000001000f9c4b cefclient`CefRunMessageLoop() + 27 at libcef_dll_wrapper.cc:295

    frame #48: 0x0000000100060eff cefclient`client::MainMessageLoopStd::Run(this=0x0000000121308dd0) + 31 at main_message_loop_std.cc:15

    frame #49: 0x0000000100028ae3 cefclient`client::(anonymous namespace)::RunMain(argc=1, argv=0x00007fff5fbffb08) + 1235 at cefclient_mac.mm:232

    frame #50: 0x00000001000285e0 cefclient`main(argc=1, argv=0x00007fff5fbffb08) + 48 at cefclient_mac.mm:252

    frame #51: 0x0000000100004794 cefclient`start + 52

[Ken Rockot]

Some additional context is here: https://bugs.chromium.org/p/chromium/issues/detail?id=594419

TL;DR: Known issue, harmless error, and it can be safely ignored for now. We don't want to suppress it because it will eventually indicate a real problem. We'll make the spam go away soon.

[Ken Rockot]

Also -mojo-dev +chromium-mojo for the appropriate list