It is a new crash signature that exists in trunk. There is a spike in crashes from 4.0b9pre/20101220. It is #16 top crasher in this build. Dupe of bug 620512? Signature nsPluginInstanceOwner::UseLayers() UUID 959025a7-b4d4-489d-91fb-75c1b2101221 Time 2010-12-21 12:03:42.515484 Uptime 338 Last Crash 342 seconds (5.7 minutes) before submission Install Age 2890 seconds (48.2 minutes) since version was first installed. Product Firefox Version 4.0b9pre Build ID 20101221030401 Branch 2.0 OS Windows NT OS Version 5.1.2600 Service Pack 3 CPU x86 CPU Info GenuineIntel family 15 model 4 stepping 9 Crash Reason EXCEPTION_ACCESS_VIOLATION_EXEC Crash Address 0xffffffffb3c8e904 User Comments App Notes AdapterVendorID: 8086, AdapterDeviceID: 29c2 MSAFD Tcpip [TCP/IP] : 2 : 1 : MSAFD Tcpip [UDP/IP] : 2 : 2 : %SystemRoot%\system32\mswsock.dll MSAFD Tcpip [RAW/IP] : 2 : 3 : %SystemRoot%\system32\mswsock.dll RSVP UDP Service Provider : 6 : 2 : %SystemRoot%\system32\rsvpsp.dll RSVP TCP Service Provider : 6 : 1 : %SystemRoot%\system32\rsvpsp.dll MSAFD NetBIOS [\Device\NetBT_Tcpip_{EFF39E60-AA81-4958-AB2F-F7367C197346}] SEQPACKET 0 : 2 : 5 : %SystemRoot%\system32\mswsock.dll MSAFD NetBIOS [\Device\NetBT_Tcpip_{EFF39E60-AA81-4958-AB2F-F7367C197346}] DATAGRAM 0 : 2 : 2 : %SystemRoot%\system32\mswsock.dll MSAFD NetBIOS [\Device\NetBT_Tcpip_{5E976B5B-4C85-4918-A327-E5FCC6439F97}] SEQPACKET 3 : 2 : 5 : %SystemRoot%\system32\mswsock.dll MSAFD NetBIOS [\Device\NetBT_Tcpip_{5E976B5B-4C85-4918-A327-E5FCC6439F97}] DATAGRAM 3 : 2 : 2 : %SystemRoot%\system32\mswsock.dll MSAFD NetBIOS [\Device\NetBT_Tcpip_{2DC5AC49-15EA-4499-955B-EE5CE54D12AC}] SEQPACKET 1 : 2 : 5 : %SystemRoot%\syste Frame Module Signature [Expand] Source 0 @0xb3c8e904 1 xul.dll nsPluginInstanceOwner::UseLayers layout/generic/nsObjectFrame.cpp:474 2 xul.dll nsObjectFrame::BuildDisplayList layout/generic/nsObjectFrame.cpp:1470 3 xul.dll nsIFrame::BuildDisplayListForChild layout/generic/nsFrame.cpp:1761 4 xul.dll nsHTMLContainerFrame::DisplayTextDecorationsAndChildren layout/generic/nsHTMLContainerFrame.cpp:393 5 xul.dll nsInlineFrame::BuildDisplayList layout/generic/nsInlineFrame.cpp:189 6 xul.dll nsIFrame::BuildDisplayListForChild layout/generic/nsFrame.cpp:1718 7 xul.dll nsBlockFrame::BuildDisplayList layout/generic/nsBlockFrame.cpp:6219 ... 58 xul.dll nsIFrame::BuildDisplayListForChild layout/generic/nsFrame.cpp:1716 59 xul.dll nsBoxFrame::BuildDisplayListForChildren layout/xul/base/src/nsBoxFrame.cpp:1355 60 xul.dll nsRootBoxFrame::BuildDisplayList layout/xul/base/src/nsRootBoxFrame.cpp:250 61 xul.dll nsIFrame::BuildDisplayListForChild layout/generic/nsFrame.cpp:1718 62 xul.dll nsIFrame::BuildDisplayListForStackingContext layout/generic/nsFrame.cpp:1467 63 xul.dll nsRootPresContext::GetPluginGeometryUpdates layout/base/nsPresContext.cpp:2530 64 xul.dll nsRootPresContext::UpdatePluginGeometry 65 xul.dll PresShell::FlushPendingNotifications layout/base/nsPresShell.cpp:4899 66 xul.dll nsDocument::FlushPendingNotifications content/base/src/nsDocument.cpp:6436 67 mozalloc.dll moz_xmalloc memory/mozalloc/mozalloc.cpp:98 68 xul.dll nsGenericElement::GetBoundingClientRect content/base/src/nsGenericElement.cpp:1739 69 xul.dll nsIDOMNSElement_GetBoundingClientRect obj-firefox/js/src/xpconnect/src/dom_quickstubs.cpp:9153 70 mozjs.dll js::Interpret js/src/jsinterp.cpp:4744 The regression range for the spike is: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=be8006fc9c4a&tochange=fc50c521bf48 More reports at: http://crash-stats.mozilla.com/report/list?product=Firefox&query_search=signature&query_type=exact&query=&range_value=4&range_unit=weeks&hang_type=any&process_type=any&plugin_field=&plugin_query_type=&plugin_query=&do_query=1&admin=&signature=nsPluginInstanceOwner%3A%3AUseLayers%28%29

Yeah I think it's a dup

http://crash-stats.mozilla.com/report/list?product=Firefox&query_search=signature&query_type=exact&query=nsPluginInstanceOwner%3A%3AUseLayers%28%29&date=01%2F02%2F2011%2016%3A54%3A43&range_value=2&range_unit=weeks&hang_type=any&process_type=any&plugin_field=&plugin_query_type=&plugin_query=&do_query=1&admin=&signature=nsPluginInstanceOwner%3A%3AUseLayers%28%29 Spike looks fixed. Only one crash in a build later than 12/23. Fixed per https://bugzilla.mozilla.org/show_bug.cgi?id=620794#c4.

As per today's meeting, beta 9 will be a time-based release. Marking these all betaN+. Please move it back to beta9+ if you believe it MUST be in the next beta (ie: trunk is in an unshippable state without this)