Bug 81114

Summary:

ASSERT(!needsLayout()) in FrameView::paintContents() with multiple nested iframes, when frame flattening is on

Product:

WebKit

Reporter:

alan <zalan>

Component:

Layout and Rendering

Assignee:

alan <zalan>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

dglazkov, kenneth, koivisto, max.hong.shen, webkit.review.bot, yael

Priority:

Version:

528+ (Nightly build)

Hardware:

Unspecified

OS:

Unspecified

URL:

http://www.iol.ie/~mariah/dbrooks/delon.html

Attachments:

Description	Flags
Patch	none
Archive of layout-test-results from ec2-cr-linux-01	none
Patch	none
Patch	koivisto: review+, koivisto: commit-queue-
Patch	none

alan

Reported 2012-03-14 08:41:13 PDT

In case of multiple nested iframes, when the bottom most iframe has a blocking resource and there's a call to paint the tree, before the blocking resource arrives, FrameView::paintContens() asserts with !needsLayout(). this behavior can be seen at www.iol.ie/~mariah/dbrooks/delon.html when clicking on Tag Board link. simplified test case: <html><body><iframe src="data:text/html,<html><body><iframe src='http://dl.dropbox.com/u/36138203/cbox.html'></iframe></body></html>"></iframe></body></html> where cbox.html is a simple page with a blocking resource. <html><head><script src="notfound.js" type="text/javascript"></script></head><body></body></html>

Attachments
Patch (6.92 KB, patch) 2012-03-26 11:43 PDT, alan	no flags	Details Formatted Diff Diff
Archive of layout-test-results from ec2-cr-linux-01 (9.80 MB, application/zip) 2012-03-26 12:56 PDT, WebKit Review Bot	no flags	Details
Patch (7.66 KB, patch) 2012-03-27 08:09 PDT, alan	no flags	Details Formatted Diff Diff
Patch (8.08 KB, patch) 2012-04-03 08:52 PDT, alan	koivisto: review+ koivisto: commit-queue-	Details Formatted Diff Diff
Patch (8.41 KB, patch) 2012-04-03 13:57 PDT, alan	no flags	Details Formatted Diff Diff
Show Obsolete (4) View All Add attachment proposed patch, testcase, etc.

alan

Comment 1 2012-03-14 09:43:12 PDT

steps leading to assertion: 1, When the bottommost iframes loads, FrameView/RenderView are constructed and get marked dirty. (markContainingBlocksForLayout ) 2, Parser stops at the script element. 3, Viewport requests painting. 5, updateLayoutAndStyleIfNeededRecursive(mainframe) is called to clean the render tree recursively before performing painting. 4, At this point only the newly constructed, bottommost FrameView is dirty. Both its parent and its parent's parent (mainframe) are clean (due to previous layouts) 5, layout() is called on the bottommost FrameView, which in turn re-initiates the layout flow from the topmost FrameView and expects that the layouting will reach itself. 6, Since parent FrameViews are clean, layouting stops at the topmost frame. 7, Bottommost FrameView's layout returns with dirty tree. No assertion happens: 1, When the blocking resource is not present and parsing hits <body>. HTMLBodyElement::insertedIntoDocument() schedules relayout on the current (bottommost) FrameView, which in turn marks its parent dirty. 2, When there's one less nested iframe. The layout works accidentally in this case. At step 6, when layout(mainframe) performs post layout tasks, it calls updateWidgetPositions(), which eventually calls layout on direct (dirty)child frames. So getting the bottommost tree clean does not happen as the result of the normal layout flow (FrameView(mainframe)->RenderView->...->RenderIFrame->FrameView(child)), but as the result of perform post layout task.

alan

Comment 2 2012-03-26 11:43:57 PDT

Created attachment 133856 [details] Patch

WebKit Review Bot

Comment 3 2012-03-26 12:56:15 PDT

Comment on attachment 133856 [details] Patch Attachment 133856 [details] did not pass chromium-ews (chromium-xvfb): Output: http://queues.webkit.org/results/12145013 New failing tests: http/tests/misc/iframe-flattening-3level-nesting-with-blocking-resource.html

WebKit Review Bot

Comment 4 2012-03-26 12:56:22 PDT

Created attachment 133871 [details] Archive of layout-test-results from ec2-cr-linux-01 The attached test failures were seen while running run-webkit-tests on the chromium-ews. Bot: ec2-cr-linux-01 Port: <class 'webkitpy.common.config.ports.ChromiumXVFBPort'> Platform: Linux-2.6.35-28-virtual-x86_64-with-Ubuntu-10.10-maverick

alan

Comment 5 2012-03-27 08:09:22 PDT

Created attachment 134066 [details] Patch

alan

Comment 6 2012-03-27 08:10:45 PDT

"CONSOLE MESSAGE: line 7: Uncaught TypeError: Object [object Object] has no method 'setFrameFlatteningEnabled'" chromium-ews failed on setFrameFlatteningEnabled(). Added to skip list similarly to all the other frame flattening tests.

alan

Comment 7 2012-04-03 08:52:12 PDT

Created attachment 135337 [details] Patch

Antti Koivisto

Comment 8 2012-04-03 12:28:55 PDT

Comment on attachment 135337 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=135337&action=review > Source/WebCore/ChangeLog:9 > + When frame flattening is on, childframes try to mark ancestors dirty to be able to restart > + layout from mainframe. When marking ancestor fails, childframe layout needs to continue normally. You should explain what the case where marking ancestors fails is and why it is not an error. > LayoutTests/platform/chromium/test_expectations.txt:724 > WONTFIX SKIP : fast/frames/flattening = TIMEOUT > +WONTFIX SKIP : http/tests/misc/iframe-flattening-3level-nesting-with-blocking-resource.html = TIMEOUT Please check that other platforms are ok with this when landing.

alan

Comment 9 2012-04-03 13:47:02 PDT

(In reply to comment #8) > (From update of attachment 135337 [details]) > View in context: https://bugs.webkit.org/attachment.cgi?id=135337&action=review > > > Source/WebCore/ChangeLog:9 > > + When frame flattening is on, childframes try to mark ancestors dirty to be able to restart > > + layout from mainframe. When marking ancestor fails, childframe layout needs to continue normally. > > You should explain what the case where marking ancestors fails is and why it is not an error. > > > LayoutTests/platform/chromium/test_expectations.txt:724 > > WONTFIX SKIP : fast/frames/flattening = TIMEOUT > > +WONTFIX SKIP : http/tests/misc/iframe-flattening-3level-nesting-with-blocking-resource.html = TIMEOUT > > Please check that other platforms are ok with this when landing. other platforms do implement layoutTestController.setFrameFlatteningEnabled

alan

Comment 10 2012-04-03 13:57:29 PDT

Created attachment 135418 [details] Patch

WebKit Review Bot

Comment 11 2012-04-03 14:35:25 PDT

Comment on attachment 135418 [details] Patch Clearing flags on attachment: 135418 Committed r113091: <http://trac.webkit.org/changeset/113091>

WebKit Review Bot

Comment 12 2012-04-03 14:35:43 PDT

All reviewed patches have been landed. Closing bug.

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