1393956 - Crash in arena_dalloc_small | free_impl | std::vector<T>::_Reallocate

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

[Marcia Knous [:marcia]]

This bug was filed from the Socorro interface and is 
report bp-683890bc-6dff-45a2-86a0-4d9750170825.
=============================================================

New crash which started in 20170825100126: http://bit.ly/2xzLwvW. 3 crashes/3 installs.

Comment 1

[Xidorn Quan [:xidorn] UTC+10]

The crashes happen on gpu process... I don't quite think we have anything to do with gpu process, so it sounds unrelated to stylo to me.

Comment 2

[Chris Peterson [:cpeterson]]

I think this is a WebRender bug, not a Stylo bug. The stack track includes a function in the `mozilla::wr::` namespace.

I see 9 crash reports with this signature in the last week. 6 have Stylo enabled, but 3 don't.

Comment 3

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

Maybe OOM? Happens inside font goop invoked from Moz2DRenderCallback.

Comment 4

[Lee Salzman [:lsalzman]]

Attachment: ensure NativeFontResourceDWrite is thread-safe

Given that the crash is happened deep inside of a free in NativeFontResourceDWrite, instead of an allocation, and given that this is happening during modification of a std::unordered_map which is known to not be thread-safe in that way, it would appear that this is some sort of race rather than that OOM.

To that end, this patch tries to make NativeFontResourceDWrite actually thread-safe. A mutex is used to guard the std::unordered_map, and the refcount in DWriteFontFileStream is made atomic.

Comment 5

[Bas Schouten (:bas.schouten)]

Comment on attachment 8903588 [details] [diff] [review]
ensure NativeFontResourceDWrite is thread-safe

Review of attachment 8903588 [details] [diff] [review]:
-----------------------------------------------------------------

Okay I guess, make sure this doesn't hurt performance.

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/19a399059c8b
ensure NativeFontResourceDWrite is thread-safe. r=bas

Comment 7

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

https://hg.mozilla.org/mozilla-central/rev/19a399059c8b