Branch: refs/heads/main
Home: https://github.com/WebKit/WebKit
Commit: 2cce60119e858731f8018bdb692ea20843133c37
https://github.com/WebKit/WebKit/commit/2cce60119e858731f8018bdb692ea20843133c37
Author: Chris Dumez <[email protected]>
Date: 2026-04-22 (Wed, 22 Apr 2026)
Changed paths:
M Source/WebCore/html/parser/HTMLParserScheduler.cpp
M Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenPlugIn.mm
M Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.h
M Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.mm
Log Message:
-----------
HTMLParserScheduler resume timer should not fire while parser yield tokens
are active
https://bugs.webkit.org/show_bug.cgi?id=312867
Reviewed by Ryosuke Niwa.
When a DocumentParserYieldToken is released and immediately retaken,
didEndYieldingParser() schedules a 0s resume timer, and then
didBeginYieldingParser() sets yield tokens active again. When the timer
fires, continueNextChunkTimerFired() calls pumpTokenizer() which asserts
!isScheduledForResume() — but that returns true because yield tokens are
active, causing an assertion failure. In release builds, this leads to a
busy-loop through the event loop until the yield tokens are cleared.
Fix this by checking m_documentHasActiveParserYieldTokens in
continueNextChunkTimerFired() and returning early, letting
didEndYieldingParser() handle scheduling the resume when tokens are
eventually released.
Tests: Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenPlugIn.mm
Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.h
Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.mm
* Source/WebCore/html/parser/HTMLParserScheduler.cpp:
(WebCore::HTMLParserScheduler::continueNextChunkTimerFired):
* Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenPlugIn.mm:
(-[ParserYieldTokenPlugIn releaseAndRetakeDocumentParserToken]):
* Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.h:
* Tools/TestWebKitAPI/Tests/WebKit/WKWebView/ParserYieldTokenTests.mm:
(TEST(ParserYieldTokenTests, ReleaseAndRetakeYieldTokenDoesNotCrash)):
Canonical link: https://commits.webkit.org/311753@main
To unsubscribe from these emails, change your notification settings at
https://github.com/WebKit/WebKit/settings/notifications
