1394337 - Fix uninitailzed mPipelineId by WebRenderBridgeParent::CreateDestroyed()

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, enhancement)

Description

[Sotaro Ikeda [:sotaro]]

Current WebRenderBridgeParent::CreateDestroyed() causes to leak CompositorBridgeParent::LayerTreeState.

Comment 1

[Sotaro Ikeda [:sotaro]]

(In reply to Sotaro Ikeda [:sotaro  PTO 1/Sep - 13/Sep] from comment #0)
> Current WebRenderBridgeParent::CreateDestroyed() causes to leak
> CompositorBridgeParent::LayerTreeState.

WebRenderBridgeParent holded uninitailzed mPipelineId when it was created by WebRenderBridgeParent::CreateDestroyed().

Comment 2

[Sotaro Ikeda [:sotaro]]

Attachment: patch - Fix WebRenderBridgeParent::CreateDestroyed()

Comment 3

[Sotaro Ikeda [:sotaro]]

(In reply to Sotaro Ikeda [:sotaro  PTO 1/Sep - 13/Sep] from comment #1)
> 
> WebRenderBridgeParent holded uninitailzed mPipelineId when it was created by
> WebRenderBridgeParent::CreateDestroyed().

mPipelineId is used as layers id like CrossProcessCompositorBridgeParent::DeallocPWebRenderBridgeParent()

   https://dxr.mozilla.org/mozilla-central/source/gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp#251

Comment 4

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8901720 [details] [diff] [review]
patch - Fix WebRenderBridgeParent::CreateDestroyed()

Review of attachment 8901720 [details] [diff] [review]:
-----------------------------------------------------------------

Please update the commit message to describe in more detail what the problem is how the patch fixes it.

From looking at the code I don't see how this is a memory leak, because the CrossProcessCompositorBridgeParent should never be getting registered in the sIndirectLayerTrees structure at all. Instead what I would expect is that when CrossProcessCompositorBridgeParent::DeallocPWebRenderBridgeParent is called, it will call EraseLayerState with some garbage uninitialized value, and so it will erase some random layer state entry. Is that correct?

Comment 5

[Sotaro Ikeda [:sotaro]]

(In reply to Kartikaya Gupta (email:[e-mail]) from comment #4)
> 
> Please update the commit message to describe in more detail what the problem
> is how the patch fixes it.
> 
> From looking at the code I don't see how this is a memory leak, because the
> CrossProcessCompositorBridgeParent should never be getting registered in the
> sIndirectLayerTrees structure at all. Instead what I would expect is that
> when CrossProcessCompositorBridgeParent::DeallocPWebRenderBridgeParent is
> called, it will call EraseLayerState with some garbage uninitialized value,
> and so it will erase some random layer state entry. Is that correct?

Yes. I am going to update the commit message.

Comment 6

[Sotaro Ikeda [:sotaro]]

Attachment: patch - Fix uninitailzed mPipelineId by WebRenderBridgeParent::CreateDestroyed()

Updated the comment.

Comment 7

[Sotaro Ikeda [:sotaro]]

Constructor needs to be updated.
 https://treeherder.mozilla.org/#/jobs?repo=try&revision=9c56bf1d31ff60032bd02939ab7fc31d27b3f245

Comment 8

[Sotaro Ikeda [:sotaro]]

Attachment: patch - Fix uninitailzed mPipelineId by WebRenderBridgeParent::CreateDestroyed()

Comment 9

[Sotaro Ikeda [:sotaro]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=79ea8300d99bbdb5ab8e30fd9c7fc49c445e275f

Comment 10

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8902073 [details] [diff] [review]
patch - Fix uninitailzed mPipelineId by WebRenderBridgeParent::CreateDestroyed()

Review of attachment 8902073 [details] [diff] [review]:
-----------------------------------------------------------------

s/uninitailzed/uninitialized/ in the commit message

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/cf44180cc29a
Fix uninitialized mPipelineId by WebRenderBridgeParent::CreateDestroyed() r=kats

Comment 12

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/cf44180cc29a