Closed Bug 1515873 Opened 4 years ago Closed 4 years ago

Crash in mozilla::MediaManager::GetBackend


(Core :: WebRTC: Audio/Video, defect, P2)

64 Branch



Tracking Status
firefox-esr60 --- unaffected
firefox64 --- wontfix
firefox65 --- fixed
firefox66 --- fixed


(Reporter: philipp, Assigned: pehrsons)



(Keywords: crash, regression)

Crash Data


(2 files, 1 obsolete file)

This bug was filed from the Socorro interface and is
report bp-ba6fe475-33f6-4e21-bd89-880a80181221.

Top 10 frames of crashing thread:

0 xul.dll class mozilla::MediaEngine* mozilla::MediaManager::GetBackend dom/media/MediaManager.cpp:3516
1 xul.dll nsresult mozilla::media::LambdaTask<`lambda at z:/build/build/src/dom/media/MediaManager.cpp:3569:38'>::Run dom/media/systemservices/MediaTaskUtils.h:37
2 xul.dll bool MessageLoop::DeferOrRunPendingTask ipc/chromium/src/base/
3 xul.dll MessageLoop::DoWork ipc/chromium/src/base/
4 xul.dll mozilla::ipc::MessagePumpForNonMainUIThreads::DoRunLoop ipc/glue/MessagePump.cpp:403
5 xul.dll base::MessagePumpWin::Run ipc/chromium/src/base/message_pump_win.h:80
6 xul.dll MessageLoop::RunHandler ipc/chromium/src/base/
7 xul.dll base::Thread::ThreadMain ipc/chromium/src/base/
8 xul.dll static unsigned long `anonymous namespace'::ThreadFunc ipc/chromium/src/base/
9 kernel32.dll BaseThreadInitThunk 


crash reports during shutdown with this signature and MOZ_RELEASE_ASSERT(!sHasShutdown) are appearing cross-platform in desktop versions of firefox 64.
Rank: 15
Priority: -- → P2
It seems to me like OnNavigation has started occurring *after* shutdown occasionally, sometime in 64.

We should detect this in OnNavigation and avoid trying to clean up more things after shutdown has occurred.
Assignee: nobody → apehrson
There's no guarantee a backend exists when a MediaManager does, and
crash-stats shows that shutdown can occur between posting a task and running
it, making it illegal to create a backend anew.

We're safer off avoiding creating a new backend. The cleanup step we're trying
to do is only effective if a backend already exists anyway.
Attachment #9033908 - Attachment is obsolete: true
Pushed by
Remove aWindowId arg from MediaManager::GetBackend. r=jib
Don't create a backend as part of cleanup. r=jib
Closed: 4 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla66
Comment on attachment 9034095 [details]
Bug 1515873 - Don't create a backend as part of cleanup. r?jib

[Beta/Release Uplift Approval Request]

Feature/Bug causing the regression: unclear

User impact if declined: Potential shutdown crash

Is this code covered by automated tests?: No

Has the fix been verified in Nightly?: No

Needs manual test from QE?: No

If yes, steps to reproduce: 

List of other uplifts needed: None

Risk to taking this patch: Low

Why is the change risky/not risky? (and alternatives if risky): Trivial

String changes made/needed: None
Attachment #9034095 - Flags: approval-mozilla-beta?
Comment on attachment 9034095 [details]
Bug 1515873 - Don't create a backend as part of cleanup. r?jib

[Triage Comment]
Minor fix to avoid a shutdown crash introduced in Fx64. Approved for 65.0b9. Given the frequency, we may want to keep this on the radar for possible dot release inclusion also.
Attachment #9034095 - Flags: approval-mozilla-beta? → approval-mozilla-beta+
See Also: → 1753316
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