This bug was filed from the Socorro interface and is report bp-53d9068a-3025-4bdc-9769-2d2422170109. ============================================================= Fair number of crashes in the worker ScriptLoader at address 0x2c when using CacheStorage. Guessing this is a ScriptLoader problem and not a CacheStorage problem.

This is happening because we try to delete the Cache when we cancel, but we may not be fully initialized if the cancel is initiated here: https://dxr.mozilla.org/mozilla-central/source/dom/workers/ScriptLoader.cpp#601

Andrea, this handles the case where we cancel worker script loading here: https://dxr.mozilla.org/mozilla-central/source/dom/workers/ScriptLoader.cpp#601 Depending on when RunInternal() returns an error we may not have initialized the mCacheStorage yet. So we cannot unconditionally use it in cancellation.

BTW, this accounts for 70% of the crashes related to dom::cache between Dec 1 and Jan 9. About 500 crashes.

Pushed by bkelly@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/8bb63d1c87d7 Handle partial initialized when ScriptLoader is canceled. r=baku

Comment on attachment 8825095 [details] [diff] [review] Handle partial initialized when ScriptLoader is canceled. r=baku Approval Request Comment [Feature/Bug causing the regression]: Service workers [User impact if declined]: About 200 crashes per week in release channel. [Is this code covered by automated tests?]: Yes, but it does not trigger this corner case. [Has the fix been verified in Nightly?]: Its very racy, so we have not been able to reproduce manually. [Needs manual test from QE? If yes, steps to reproduce]: None [List of other uplifts needed for the feature/fix]: None [Is the change risky?]: No [Why is the change risky/not risky?]: Its simply an extra nullptr check. Its very low risk. [String changes made/needed]: None

Comment on attachment 8825095 [details] [diff] [review] Handle partial initialized when ScriptLoader is canceled. r=baku Fix a crash. Beta51+ & Aurora52+. Should be in 51 beta 14.