This bug was filed from the Socorro interface and is report bp-4f6a5639-e03f-43de-a793-6b2760180501. ============================================================= Top 10 frames of crashing thread: 0 xul.dll mozilla::layers::PaintThread::PaintTiledContents gfx/layers/PaintThread.cpp:381 1 xul.dll mozilla::layers::ClientSingleTiledLayerBuffer::PaintThebes gfx/layers/client/SingleTiledContentClient.cpp:312 2 xul.dll mozilla::layers::ClientTiledPaintedLayer::RenderHighPrecision gfx/layers/client/ClientTiledPaintedLayer.cpp:353 3 xul.dll mozilla::layers::ClientTiledPaintedLayer::RenderLayer gfx/layers/client/ClientTiledPaintedLayer.cpp:555 4 xul.dll mozilla::layers::ClientContainerLayer::RenderLayer gfx/layers/client/ClientContainerLayer.h:58 5 xul.dll mozilla::layers::ClientContainerLayer::RenderLayer gfx/layers/client/ClientContainerLayer.h:58 6 xul.dll mozilla::layers::ClientLayerManager::EndTransactionInternal gfx/layers/client/ClientLayerManager.cpp:359 7 xul.dll mozilla::layers::ClientLayerManager::EndTransaction gfx/layers/client/ClientLayerManager.cpp:423 8 xul.dll nsDisplayList::PaintRoot layout/painting/nsDisplayList.cpp:2761 9 xul.dll nsLayoutUtils::PaintFrame layout/base/nsLayoutUtils.cpp:3827 ============================================================= There are 48 crashes (from 21 installations) in nightly 61 starting with buildid 20180501102731. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1454978. [1] https://hg.mozilla.org/mozilla-central/rev?node=2ba500ed529b

My guess is this is caused by us not creating the paint workers at startup because the conditions for using tiling are not met, and then it dynamically changes with a device reset or something. The attached patch should make sure in cases we can dynamically switch, we have created the paint worker threads.

Comment on attachment 8972585 [details] Bug 1458462 - Create paint workers if it's possible we could switch to tiling in the future. https://reviewboard.mozilla.org/r/241150/#review247212

Pushed by rhunt@eqrion.net: https://hg.mozilla.org/integration/mozilla-inbound/rev/895146c6b6bc Create paint workers if it's possible we could switch to tiling in the future. r=nical