RESOLVED INVALID 11592
deadlock in UI between two threads trying to draw to screen 
https://bugs.webkit.org/show_bug.cgi?id=11592
Summary deadlock in UI between two threads trying to draw to screen
Dan Wood
Reported 2006-11-13 14:16:35 PST
In my webkit-using app, I came across an interesting UI deadlock. The main thread, in my code, was calling -[NSView displayIfNeeded] -> -[NSViewHierarchyLock lockForReadingWithExceptionHandler:] -> pthread_cond_wait .... But there was another thread, spawned by +[NSURLConnection(NSURLConnectionInternal) _resourceLoadLoop:] that was responding to data being available in the webview -[WebMainResourceClient didReceiveData:lengthReceived:] that deadlocked with thread 1. The backtrace from a sample will be attached as a sample since it won't reproduce well in this text field. I have only had this happen once, unfortunately. but maybe somebody can understand why a backgrond thread is messing with the UI and locking with thread 1.
Attachments
sample showing deadlock (4.89 KB, text/plain)
2006-11-13 14:17 PST, Dan Wood 		no flags
Details
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Dan Wood
Comment 1 2006-11-13 14:17:10 PST
Created attachment 11510 [details] sample showing deadlock
Alexey Proskuryakov
Comment 2 2007-04-25 06:13:59 PDT
This may be related to <rdar://4474791> NSURLConnection delegate called on a wrong thread - though my report was about connection:willCacheResponse:. In any case, this is an NSURLConnection bug, and should be filed via Radar. Personally, I wouldn't file it unless I could reproduce it with a Leopard seed.
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