1270797 - Crash due to stack overflow in ComputeEffectiveTransformsForChildren

Status: RESOLVED FIXED

(Core :: Graphics: Layers, defect)

Description

[Carsten Book [:Tomcat]]

Found via bughunter and reproduced on a windows 7 debug build as well as on a nightly opt build based on m-c tip also on mac

Steps to reproduce: 
--> Load https://prevoty.com/
----> Crash

Comment 1

[Carsten Book [:Tomcat]]

Attachment: bughunter stack

and https://crash-stats.mozilla.com/report/index/ebefcb42-18e7-4ccf-a0a9-579652160506 for the opt crash

Comment 2

[Jeff Muizelaar [:jrmuizel]]

Maybe layout should avoid putting us in this situation?

Comment 3

[Matt Woodrow (:mattwoodrow)]

Attachment: double-blend-container

Comment 4

[Markus Stange [:mstange]]

Why is this necessary? What's happening here? Don't we still need different keys for different nsDisplayBlendMode items for the same frame?

Comment 5

[Matt Woodrow (:mattwoodrow)]

The problem is that we build two nsDisplayBlendContainers for the same frame, and FrameLayerBuilder gets confused and builds a ContainerLayer with itself as its first child.

We had mIndex to prevent this, but it was always zero, so didn't do anything.

As far as I can tell we can only ever have two blend containers per frame (one for mix-blend-mode, and one for background-blend-mode), so switching to a boolean seems sufficient (and clearer).

We can still build an arbitrary number of nsDisplayBlendModes, but those already use indexes correctly.

Comment 6

[Markus Stange [:mstange]]

Oops, I got confused with nsDisplayBlendContainer vs nsDisplayBlendMode. Sounds good.

Comment 7

[Markus Stange [:mstange]]

Comment on attachment 8750546 [details] [diff] [review]
double-blend-container

Review of attachment 8750546 [details] [diff] [review]:
-----------------------------------------------------------------

thanks

Comment 8

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/486e823cb780

Comment 9

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/486e823cb780