Changeset 162063 in webkit

Timestamp:

Jan 15, 2014, 2:28:52 AM (11 years ago)

Author:

Antti Koivisto

Message:

Suspend resource requests during computedStyle
​https://bugs.webkit.org/show_bug.cgi?id=127034

Reviewed by Andreas Kling.

We have some cases where getting computed style leads to crashes in loadPendingImages.
This is probably caused by load callbacks resulting in re-entering WebKit and killing the StyleResolver.

As a speculative fix suspend resource loads (and so callbacks) when getting the computed style.
We do similar suspension during style recalc for the same reason.

• dom/Document.cpp:

(WebCore::Document::styleForElementIgnoringPendingStylesheets):

• loader/ResourceLoadScheduler.h:

(WebCore::ResourceLoadScheduler::Suspender::Suspender):
(WebCore::ResourceLoadScheduler::Suspender::~Suspender):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• dom/Document.cpp (modified) (4 diffs)
• loader/ResourceLoadScheduler.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-01-15  Antti Koivisto  <antti@apple.com>
+
+        Suspend resource requests during computedStyle
+        https://bugs.webkit.org/show_bug.cgi?id=127034
+
+        Reviewed by Andreas Kling.
+
+        We have some cases where getting computed style leads to crashes in loadPendingImages. 
+        This is probably caused by load callbacks resulting in re-entering WebKit and killing the StyleResolver.
+        
+        As a speculative fix suspend resource loads (and so callbacks) when getting the computed style.
+        We do similar suspension during style recalc for the same reason.
+
+        * dom/Document.cpp:
+        (WebCore::Document::styleForElementIgnoringPendingStylesheets):
+        * loader/ResourceLoadScheduler.h:
+        (WebCore::ResourceLoadScheduler::Suspender::Suspender):
+        (WebCore::ResourceLoadScheduler::Suspender::~Suspender):
+
 2014-01-15  László Langó  <llango.u-szeged@partner.samsung.com>
 

trunk/Source/WebCore/dom/Document.cpp

@@ -93 +93 @@
 #include "JSLazyEventListener.h"
 #include "Language.h"
+#include "LoaderStrategy.h"
 #include "Logging.h"
 #include "MainFrame.h"
@@ -108 +109 @@
 #include "PageTransitionEvent.h"
 #include "PlatformLocale.h"
+#include "PlatformStrategies.h"
 #include "PlugInsResources.h"
 #include "PluginDocument.h"
@@ -115 +117 @@
 #include "RenderView.h"
 #include "RenderWidget.h"
+#include "ResourceLoadScheduler.h"
 #include "ResourceLoader.h"
 #include "RuntimeEnabledFeatures.h"
@@ -1866 +1869 @@
 {
     ASSERT_ARG(element, &element->document() == this);
+
+    // On iOS request delegates called during styleForElement may result in re-entering WebKit and killing the style resolver.
+    ResourceLoadScheduler::Suspender suspender(*platformStrategies()->loaderStrategy()->resourceLoadScheduler());
 
     TemporaryChange<bool> change(m_ignorePendingStylesheets, true);

trunk/Source/WebCore/loader/ResourceLoadScheduler.h

@@ -63 +63 @@
     virtual void setSerialLoadingEnabled(bool b) { m_isSerialLoadingEnabled = b; }
 
+    class Suspender {
+    public:
+        explicit Suspender(ResourceLoadScheduler& scheduler) : m_scheduler(scheduler) { m_scheduler.suspendPendingRequests(); }
+        ~Suspender() { m_scheduler.resumePendingRequests(); }
+    private:
+        ResourceLoadScheduler& m_scheduler;
+    };
+
 protected:
     ResourceLoadScheduler();