Details
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Bug
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Resolution: Out of scope
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P2: Important
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None
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5.15.5
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None
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Windows 10 64bit, Intel UHD 630 graphics driver, reproduced with version 27.20.100.8681 and 30.0.100.9684
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Windows
Description
When opening a Qt window containing the QtWebView, during initialization, there is a potential deadlock. See the callstacks of 2 threads (attached pics):
- Thread 1 is the normal Qt Gui thread
opengl32.dll!wglSetPixelFormat -> ig9icd64.dll - Thread 2 is the WebEngine GPU thread
ig9icd64.dll -> opengl32.dll!wglSetPixelFormat
Both stuck in a critical section, obviously a classic deadlock.
ig9icd64.dll is the graphics driver for Intel UHD 630 graphics chip.
The problem occurs not deterministically, but (at least on one pc) quite often.
Suggested solution: Somehow synchronize the 2 threads, so that SetPixelFormat is not called parallel, but in sequence.
This is the code creating the Qt Dialog with the QtWebView (your web fronted is removing the newlines, sorry):
QWidget* HtmlDialogQt::OpenDialogWindow(QWidget* dlgwnd){
dlgwnd->resize(800, 600);
QGridLayout* gridLayout = new QGridLayout();
dlgwnd->setLayout(gridLayout);
QWebEngineView* webwidget = new QWebEngineView();
gridLayout->addWidget(webwidget);
QString path = Util::UnicodeToUTF8(m_uri.c_str()).c_str();
if (path.startsWith(L"http"))
webwidget->setUrl(QUrl(path));
else
webwidget->setUrl(QUrl::fromLocalFile(path));
webwidget->setParent(dlgwnd);
QPushButton* closeButton = new QPushButton("Close");
closeButton->setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Maximum);
gridLayout->addWidget(closeButton, 1, 0, Qt::AlignHCenter);
QObject::connect(closeButton, &QPushButton::clicked, this, &HtmlDialogQt::slotCloseButtonClicked);
dlgwnd->show();
return closeButton;
}
Thread 2 is started by setUrl()
Thread 1 is show();
