question

Gregory Keenan avatar image
Gregory Keenan asked ·

Unable to load Mtoa.so - Fatal Error - Linux

I'm very stuck on this issue and been trying to find a solution.

I've installed Maya 2022 on Ubuntu following the instructions here. After a few issues with the licenser I got it to work. However, I have not been able to get Arnold to work.

When I start Maya I get no errors or warnings from the terminal, but when the main window shows I have a warning:


// Warning: file: /usr/autodesk/maya2022/scripts/others/supportRenderers.mel line 67: The renderer "arnold" used by this scene, is not currently available. The "mayaSoftware" renderer will be used instead. To prevent this message from being displayed in the future, set the environment variable: MAYA_NO_WARNING_FOR_MISSING_DEFAULT_RENDERER=1 // 


I then go to Windows->Setting/Preferences->Plug in manager

I then find mtoa.so and click load, but then Maya has a Fatal Error. This then appears in the terminal:


Unable to execute xgen.mel.00:00:00  1523MB         | log started Mon Apr 26 22:57:29 2021
00:00:00  1523MB         | Arnold 6.2.1.0 [359aaa66] linux clang-10.0.1 oiio-2.3.2 osl-1.12.0 vdb-7.1.1 clm-2.0.0.235 rlm-14.1.3 optix-6.6.0 2021/04/21 13:54:09
00:00:00  1523MB         | running on gregory-Alienware-m15-R3, pid=4553
00:00:00  1523MB         |  1 x Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (6 cores, 12 logical) with 15762MB
00:00:00  1523MB         |  NVIDIA driver version 460.73 (Optix 60800)
00:00:00  1523MB         |  GPU 0: GeForce RTX 2070 Super @ 1380MHz (compute 7.5) with 7973MB (7642MB available) (NVLink:0)
00:00:00  1523MB         |  Ubuntu 20.04.2 LTS (Focal Fossa), Linux kernel 5.8.0-50-generic
00:00:00  1523MB         |  soft limit for open files raised from 1024 to 1048574
00:00:00  1523MB         |  
00:00:00  1523MB         | loading plugins from /usr/autodesk/arnold/maya2022/plug-ins/../bin/../plugins ...
00:00:00  1530MB         |  usd_proc.so: usd uses Arnold 6.2.1.0
00:00:00  1538MB         |  synColor_shaders.so: color_manager_syncolor uses Arnold 6.2.1.0
00:00:00  1540MB         |  cryptomatte.so: cryptomatte uses Arnold 6.2.1.0
00:00:00  1540MB         |  cryptomatte.so: cryptomatte_filter uses Arnold 6.2.1.0
00:00:00  1540MB         |  cryptomatte.so: cryptomatte_manifest_driver uses Arnold 6.2.1.0
00:00:00  1540MB         |  alembic_proc.so: alembic uses Arnold 6.2.1.0
00:00:00  1540MB         | loaded 6 plugins from 4 lib(s) in 0:00.00

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/extension/ExtensionsManager.cpp at line 736
: (kFailure): Unexpected Internal Failure

API error detected in plugins/mtoa/Main.cpp at line 1322
: (kFailure): Unexpected Internal Failure
00:00:00  1553MB ERROR   | Failed to import python module 'arnold'
00:00:00  1552MB ERROR   | signal caught: SIGSEGV -- Invalid memory reference

****
* Arnold 6.2.1.0 [359aaa66] linux clang-10.0.1 oiio-2.3.2 osl-1.12.0 vdb-7.1.1 clm-2.0.0.235 rlm-14.1.3 optix-6.6.0 2021/04/21 13:54:09
* CRASHED in Tmetaclass::isa(char const*) at 00:00:00
* signal caught: SIGSEGV -- Invalid memory reference (address not mapped to object)
*
* backtrace:
>> 0 0x00007f6d69708460 [libFoundation.so    ] Tmetaclass::isa(char const*)                                                                                                                             
*  1 0x00007f6d69708422 [libFoundation.so    ] Tmetaclass::isa(char const*)                                                                                                                             
*  2 0x00007f6d733f0137 [libOGSMayaBridge.so ] OGSMayaClassificationChangeListener::doClassificationChanged(Tstring const&, OGS::Objects::UString*, bool)                                               
*  3 0x00007f6d733f05c8 [libOGSMayaBridge.so ] OGSMayaClassificationChangeListener::classificationChangedCB(TclientServer*, TserverMsg const&)                                                          
*  4 0x00007f6d696f7be1 [libFoundation.so    ] TclientServer::notifyClients(TserverMsg const&)                                                                                                          
*  5 0x00007f6d6af51e56 [libDependEngine.so  ] TclassificationMgr::deregisterNodeType(Tstring const&)                                                                                                   
*  6 0x00007f6d72ae840c [libOpenMaya.so      ] Autodesk::Maya::OpenMaya20220000::MFnPlugin::deregisterNode(Autodesk::Maya::OpenMaya20220000::MTypeId const&)                                            
*  7 0x00007f6c2081035c [mtoa.so             ] (anonymous namespace)::UnregisterArnoldNodes(Autodesk::Maya::OpenMaya20220000::MObject)                                                                  [Main.cpp:?]
*  8 0x00007f6c208105f5 [mtoa.so             ] MtoAInitFailed(Autodesk::Maya::OpenMaya20220000::MObject, Autodesk::Maya::OpenMaya20220000::MFnPlugin&, std::vector<bool, std::allocator<bool> > const&) [        :?]
*  9 0x00007f6c20814f38 [mtoa.so             ] initializePlugin(Autodesk::Maya::OpenMaya20220000::MObject)                                                                                              
* 10 0x00007f6d72ae2dfc [libOpenMaya.so      ] Tplugin::primaryLoad(Tstring const&, Tstring*)                                                                                                           
* 11 0x00007f6d72b40bec [libOpenMaya.so      ] TpluginPref::TpluginPref()                                                                                                                               
* 12 0x00007f6d72b3fce1 [libOpenMaya.so      ] TpluginPref::TpluginPref()                                                                                                                               
* 13 0x00007f6d72b3f5c1 [libOpenMaya.so      ] TpluginPref::TpluginPref()                                                                                                                               
* 14 0x00007f6d6b14e173 [libCommandEngine.so ] TmetaCommand::setUnloadable(bool)                                                                                                                        
* 15 0x00007f6d6b1782fa [libCommandEngine.so ] f_system                                                                                                                                                 
* 16 0x00007f6d6b1998ce [libCommandEngine.so ] setMelGlobalStackLevelPtr(unsigned int (*)())                                                                                                            
* 17 0x00007f6d6b1782fa [libCommandEngine.so ] f_system                                                                                                                                                 
* 18 0x00007f6d6b198f0a [libCommandEngine.so ] setMelGlobalStackLevelPtr(unsigned int (*)())                                                                                                            
* 19 0x00007f6d6b1782fa [libCommandEngine.so ] f_system                                                                                                                                                 
* 20 0x00007f6d6b19acfc [libCommandEngine.so ] setMelGlobalStackLevelPtr(unsigned int (*)())                                                                                                            
* 21 0x00007f6d6b1782fa [libCommandEngine.so ] f_system                                                                                                                                                 
* 22 0x00007f6d6b178430 [libCommandEngine.so ] f_system                                                                                                                                                 
* 23 0x00007f6d6b19770c [libCommandEngine.so ] SophiaExecutable::evaluate(void*)                                                                                                                        
* 24 0x00007f6d6b15695d [libCommandEngine.so ] TcommandEngine::executeCommand(Tstring const&, bool, bool, TmelCmdResult*, unsigned int)                                                                 
* 25 0x00007f6d6b841ea6 [libExtensionLayer.so] TscriptActionMixin::execute(Tevent const&, std::unique_ptr<TinterpreterResult, std::default_delete<TinterpreterResult> >*)                               
* 26 0x00007f6d6b7bb2f6 [libExtensionLayer.so] TcontrolScriptAction::doIt(Tevent const&)                                                                                                                
* 27 0x00007f6d6b686751 [libExtensionLayer.so] Taction::performAction(Tevent const&, char const*)                                                                                                       
* 28 0x00007f6d6b686903 [libExtensionLayer.so] Taction::doIt()                                                                                                                                          
* 29 0x00007f6d6850d3b4 [libQt5Core.so.5     ] void doActivate<false>(QObject*, int, void**)                                                                                                            
* 30 0x00007f6d6b6bb02f [libExtensionLayer.so] QmayaCheckBox::onOffChanged()                                                                                                                            
* 31 0x00007f6d6b66da72 [libExtensionLayer.so] non-virtual thunk to QmayaFloatSliderGrp::newValueForConnections(QVariant const&, bool)                                                                  
* 32 0x00007f6d6850d3b4 [libQt5Core.so.5     ] void doActivate<false>(QObject*, int, void**)                                                                                                            
* 33 0x00007f6d6a38f00d [libQt5Widgets.so.5  ] QCheckBox::stateChanged(int)                                                                                                                             
* 34 0x00007f6d6a380abb [libQt5Widgets.so.5  ] QAbstractButtonPrivate::click()                                                                                                                          
* 35 0x00007f6d6a380cbf [libQt5Widgets.so.5  ] QAbstractButton::mouseReleaseEvent(QMouseEvent*)                                                                                                         
* 36 0x00007f6d6a2cf375 [libQt5Widgets.so.5  ] QWidget::event(QEvent*)                                                                                                                                  
* 37 0x00007f6d6a28f6fe [libQt5Widgets.so.5  ] QApplicationPrivate::notify_helper(QObject*, QEvent*)                                                                                                    
* 38 0x00007f6d6a2980b7 [libQt5Widgets.so.5  ] QApplication::notify(QObject*, QEvent*)                                                                                                                  
* 39 0x00007f6d6b68d9d5 [libExtensionLayer.so] QmayaApplication::currentMousePos()                                                                                                                      
* 40 0x00007f6d684d8f89 [libQt5Core.so.5     ] QCoreApplication::notifyInternal2(QObject*, QEvent*)                                                                                                     
* 41 0x00007f6d6a29742f [libQt5Widgets.so.5  ] QApplicationPrivate::sendMouseEvent(QWidget*, QMouseEvent*, QWidget*, QWidget*, QWidget**, QPointer<QWidget>&, bool, bool)                               
* 42 0x00007f6d6a2e947b [libQt5Widgets.so.5  ] QWidgetWindow::handleMouseEvent(QMouseEvent*)                                                                                                            
* 43 0x00007f6d6a2ec58b [libQt5Widgets.so.5  ] QWidgetWindow::event(QEvent*)                                                                                                                            
* 44 0x00007f6d6a28f6fe [libQt5Widgets.so.5  ] QApplicationPrivate::notify_helper(QObject*, QEvent*)                                                                                                    
* 45 0x00007f6d6a297ed7 [libQt5Widgets.so.5  ] QApplication::notify(QObject*, QEvent*)                                                                                                                  
* 46 0x00007f6d6b68d9d5 [libExtensionLayer.so] QmayaApplication::currentMousePos()                                                                                                                      
* 47 0x00007f6d684d8f89 [libQt5Core.so.5     ] QCoreApplication::notifyInternal2(QObject*, QEvent*)                                                                                                     
* 48 0x00007f6d6896ec77 [libQt5Gui.so.5      ] QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::MouseEvent*) [clone .localalias]                                                
* 49 0x00007f6d68970238 [libQt5Gui.so.5      ] QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*)                                                      
* 50 0x00007f6d68949e5b [libQt5Gui.so.5      ] QWindowSystemInterface::sendWindowSystemEvents(QFlags<QEventLoop::ProcessEventsFlag>)                                                                    
* 51 0x00007f6d46733d29 [libQt5XcbQpa.so.5   ] xcbSourceDispatch(_GSource*, int (*)(void*), void*)                                                                                                      
* 52 0x00007f6d50a4c17c [libglib-2.0.so.0    ] g_main_context_dispatch                                                                                                                                  
* 53 0x00007f6d50a4c3ff [libglib-2.0.so.0    ] g_main_context_dispatch                                                                                                                                  
* 54 0x00007f6d50a4c4a2 [libglib-2.0.so.0    ] g_main_context_iteration                                                                                                                                 
* 55 0x00007f6d6852ed3d [libQt5Core.so.5     ] QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)                                                                               
* 56 0x00007f6d684d7cfa [libQt5Core.so.5     ] QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)                                                                                                  
* 57 0x00007f6d684df70b [libQt5Core.so.5     ] QCoreApplication::exec()                                                                                                                                 
* 58 0x00007f6d6b6887a3 [libExtensionLayer.so] Tapplication::start()                                                                                                                                    
* 59 0x0000000000415cb2 [maya.bin            ]                                                                                                                                                          
* 60 0x000000000041447e [maya.bin            ]                                                                                                                                                          
* 61 0x00007f6d67a870b2 [libc.so.6           ] __libc_start_main                                                                                                                                        
* 62 0x0000000000415699 [maya.bin            ]                                                                                                                                                          
*
* loaded modules:
*    0x00007f6d6957c000  libFoundation.so
*    0x00007f6d7323d000  libOGSMayaBridge.so
*    0x00007f6d6abc8000  libDependEngine.so
*    0x00007f6d727f6000  libOpenMaya.so
*    0x00007f6c205db000  mtoa.so
*    0x00007f6d6b0b6000  libCommandEngine.so
*    0x00007f6d6b35e000  libExtensionLayer.so
*    0x00007f6d68230000  libQt5Core.so.5
*    0x00007f6d6a126000  libQt5Widgets.so.5
*    0x00007f6d6883e000  libQt5Gui.so.5
*    0x00007f6d466cf000  libQt5XcbQpa.so.5
*    0x00007f6d509fa000  libglib-2.0.so.0
*    0x0000000000400000  maya.bin
*    0x00007f6d67a60000  libc.so.6
*
* memory: VM 15200 MB, RSS 1555 MB, 0 page faults
****
Stack trace:
  Tmetaclass::isa(char const*)
  Tmetaclass::isa(char const*)
  OGSMayaClassificationChangeListener::doClassificationChanged(Tstring const&, OGS::Objects::UString*, bool)
  OGSMayaClassificationChangeListener::classificationChangedCB(TclientServer*, TserverMsg const&)
  TclientServer::notifyClients(TserverMsg const&)
  TclassificationMgr::deregisterNodeType(Tstring const&)
  Autodesk::Maya::OpenMaya20220000::MFnPlugin::deregisterNode(Autodesk::Maya::OpenMaya20220000::MTypeId const&)
  /usr/autodesk/arnold/maya2022/plug-ins/mtoa.so(+0x23535d) [0x7f6c2081035d]
  /usr/autodesk/arnold/maya2022/plug-ins/mtoa.so(+0x2355f6) [0x7f6c208105f6]
  initializePlugin(Autodesk::Maya::OpenMaya20220000::MObject)
  Tplugin::primaryLoad(Tstring const&, Tstring*)
  /usr/autodesk/maya2022/lib/libOpenMaya.so(+0x34abed) [0x7f6d72b40bed]
  /usr/autodesk/maya2022/lib/libOpenMaya.so(+0x349ce2) [0x7f6d72b3fce2]
  /usr/autodesk/maya2022/lib/libOpenMaya.so(+0x3495c2) [0x7f6d72b3f5c2]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0x98174) [0x7f6d6b14e174]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xc22fb) [0x7f6d6b1782fb]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xe38cf) [0x7f6d6b1998cf]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xc22fb) [0x7f6d6b1782fb]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xe2f0b) [0x7f6d6b198f0b]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xc22fb) [0x7f6d6b1782fb]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xe4cfd) [0x7f6d6b19acfd]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xc22fb) [0x7f6d6b1782fb]
  /usr/autodesk/maya2022/lib/libCommandEngine.so(+0xc2431) [0x7f6d6b178431]
  SophiaExecutable::evaluate(void*)
  TcommandEngine::executeCommand(Tstring const&, bool, bool, TmelCmdResult*, unsigned int)
  TscriptActionMixin::execute(Tevent const&, std::unique_ptr<TinterpreterResult, std::default_delete<TinterpreterResult> >*)
  TcontrolScriptAction::doIt(Tevent const&)
  Taction::performAction(Tevent const&, char const*)
  Taction::doIt()
  /usr/autodesk/maya2022/lib/libQt5Core.so.5(+0x2dd3b5) [0x7f6d6850d3b5]
  QmayaCheckBox::onOffChanged()
  /usr/autodesk/maya2022/lib/libExtensionLayer.so(+0x30fa73) [0x7f6d6b66da73]
  /usr/autodesk/maya2022/lib/libQt5Core.so.5(+0x2dd3b5) [0x7f6d6850d3b5]
  QCheckBox::stateChanged(int)
  /usr/autodesk/maya2022/lib/libQt5Widgets.so.5(+0x25aabc) [0x7f6d6a380abc]
  QAbstractButton::mouseReleaseEvent(QMouseEvent*)
  QWidget::event(QEvent*)
  QApplicationPrivate::notify_helper(QObject*, QEvent*)
  QApplication::notify(QObject*, QEvent*)
  /usr/autodesk/maya2022/lib/libExtensionLayer.so(+0x32f9d6) [0x7f6d6b68d9d6]
1Writing crash report in /usr/tmp/gregory.20210426.2257.crash
/usr/autodesk/maya2022/bin/senddmp.app/senddmp.bin: error while loading shared libraries: libpng12.so.0: cannot open shared object file: No such file or directory


My first hunch was Python, but python appears to be installed correctly on the Laptop and my looking for reasons for this error have all come up with no real results (may be I'm googling the wrong terms).


Anyone able to figure out whats going on? I've tried re-installing Arnold several times and its made no change.

arnoldinstall errorlinux
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Gregory Keenan avatar image
Gregory Keenan answered ·

So I found a workaround (for now, unsure of a proper solution). Sharing it here in case anyone stumbles upon this:


Load Maya from terminal, but BEFORE you launch Maya type the following command:

export LD_PRELOAD="/snap/core18/1988/usr/lib/x86_64-linux-gnu/libffi.so.6"


Replacing the directories to your location for libffi.so.6. (If you have python already installed, it should be on your computer).


Then launch Maya from the terminal, which for me is:

/usr/autodesk/maya2022/bin/maya


If I find a more permanent solution I will post it back here. Having done a little digging, Ubuntu 20.04 is apparently part of the problem.

Thanks again Stephen for pointing me in the right direction!

3 comments
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

The 'more permanent solution' you're probably looking for ;)

sudo ln -s /usr/lib/x86_64-linux-gnu/libffi.so.6 /usr/autodesk/maya2022/lib/libffi.so.6


1 Like 1 ·

Thank you! After a day of tearing my hair out on this, linking didn't even cross my mind.

0 Likes 0 ·

For this kind of problems, It's always somehow at least in part or to some degrees .. a linking problem :)

1 Like 1 ·
Stephen Blair avatar image
Stephen Blair answered ·

You can ignore the crash, the real problem is that MtoA is failing to load because of Python problem. (The crash is because MtoA fails to load, and then tries to deregister itself, but it tries to de-register stuff that was never registered).

Instead of loading MtoA, try to run these Python commands in the script editor, and see if anything is logged in the script history:


import arnold
import mtoa
import mtoa.cmds.registerArnoldRenderer;mtoa.cmds.registerArnoldRenderer.registerArnoldRenderer()
1 comment
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Thanks for the reply;


import arnold

# Error: ImportError: file /usr/autodesk/maya2022/lib/python3.7/site-packages/shiboken2/files.dir/shibokensupport/__feature__.py line 142: libffi.so.6: cannot open shared object file: No such file or directory # 


Both line 1 and 3 do this. import mtoa on its own doesn't produce any output.


The file __feature__.py exists. However the call the file is making on line 142 is:


return original_import(name, *args, **kwargs) 


Leading me to think it can't find libffi.so.6 - however, I was never good with Python so might be wide of the mark here.

0 Likes 0 ·

Write an Answer

Hint: Notify or tag a user in this post by typing @username.

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Welcome to the Arnold Answers community.

This is the place for Arnold renderer users everywhere to ask and answer rendering questions, and share knowledge about using Arnold, Arnold plugins, workflows and developing tools with Arnold.

If you are a new user to Arnold Answers, please first check out our FAQ and User Guide for more information.

When posting questions, please be sure to select the appropriate Space for your Arnold plugin and include the plugin version you are using.

Please include images, scene and log files whenever possible as this helps the community answer your questions.

Instructions for generating full verbosity log files are available for MtoA, MaxtoA, C4DtoA, HtoA, KtoA, and Kick.

If you are looking for Arnold Documentation and Support please visit the Arnold Support site.

To try Arnold please visit the Arnold Trial page.

Bottom No panel present for this section.