2 files changed, 14 insertions, 3 deletions
diff --git a/Source/WebCore/platform/graphics/WidthIterator.cpp b/Source/WebCore/platform/graphics/WidthIterator.cpp
index e8b620f8a..48a59a27c 100644
--- a/Source/WebCore/platform/graphics/WidthIterator.cpp
+++ b/Source/WebCore/platform/graphics/WidthIterator.cpp
@@ -124,9 +124,9 @@ static inline float applyFontTransforms(GlyphBuffer* glyphBuffer, bool ltr, int&
 #if ENABLE(SVG_FONTS)
     // We need to handle transforms on SVG fonts internally, since they are rendered internally.
     if (fontData->isSVGFont()) {
-        ASSERT(iterator.run().renderingContext());
+        // SVG font fallbacks doesn't work properly and will not have a renderingContext. see: textRunNeedsRenderingContext()
         // SVG font ligatures are handled during glyph selection, only kerning remaining.
-        if (typesettingFeatures & Kerning)
+        if (iterator.run().renderingContext() && (typesettingFeatures & Kerning))
             iterator.run().renderingContext()->applySVGKerning(fontData, iterator, glyphBuffer, lastGlyphCount);
     } else
 #endif
diff --git a/Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp b/Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp
index 55c0b6aca..4469fde58 100644
--- a/Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp
+++ b/Source/WebCore/platform/graphics/texmap/TextureMapperGL.cpp
@@ -38,6 +38,7 @@
 #include <wtf/TemporaryChange.h>
 
 #if PLATFORM(QT)
+#include <QPaintEngine>
 #include "NativeImageQt.h"
 #endif
 
@@ -908,7 +909,17 @@ void BitmapTextureGL::updateContents(Image* image, const IntRect& targetRect, co
     const char* imageData;
 
 #if PLATFORM(QT)
-    QImage qImage = frameImage->toImage();
+    QImage qImage;
+    QPaintEngine* paintEngine = frameImage->paintEngine();
+    if (paintEngine && paintEngine->type() == QPaintEngine::Raster) {
+        // QRasterPixmapData::toImage() will deep-copy the backing QImage if there's an active QPainter on it.
+        // For performance reasons, we don't want that here, so we temporarily redirect the paint engine.
+        QPaintDevice* currentPaintDevice = paintEngine->paintDevice();
+        paintEngine->setPaintDevice(0);
+        qImage = frameImage->toImage();
+        paintEngine->setPaintDevice(currentPaintDevice);
+    } else
+        qImage = frameImage->toImage();
     imageData = reinterpret_cast<const char*>(qImage.constBits());
     bytesPerLine = qImage.bytesPerLine();
 #elif USE(CAIRO)