1148640 - Bail if OnStartRequest is delivered more than once to imgCacheValidator

Status: RESOLVED FIXED

(Core :: Graphics: ImageLib, defect)

Description

[Seth Fowler [:seth] [:s2h]]

Right now I'm concerned that Necko is delivering OnStartRequest more than once, which is causing strange behavior in ImageLib. I've filed bug 1136969 about trying to detect it in Necko, but I think we should have a check in imgCacheValidator as well.

Comment 1

[Seth Fowler [:seth] [:s2h]]

Attachment: Bail if OnStartRequest is delivered more than once to imgCacheValidator

Here's the patch. This should help us detect this issue if it happens on our CI infrastructure.

Comment 2

[Seth Fowler [:seth] [:s2h]]

Thanks for the quick review! Here's a try push to make sure we don't already hit this (Linux and B2G only; hopefully that's a representative sample):

https://treeherder.mozilla.org/#/jobs?repo=try&revision=239304b45ac3

Comment 3

[Seth Fowler [:seth] [:s2h]]

Try looks good. (Or at least, it doesn't seem to contain any failures triggered by this patch.) Pushed:

https://hg.mozilla.org/integration/mozilla-inbound/rev/641902d237af

Comment 4

[Phil Ringnalda (:philor)]

https://hg.mozilla.org/mozilla-central/rev/641902d237af

Comment 5

[Seth Fowler [:seth] [:s2h]]

Comment on attachment 8584838 [details] [diff] [review]
Bail if OnStartRequest is delivered more than once to imgCacheValidator

[Approval Request Comment]
If this is not a sec:{high,crit} bug, please state case for ESR consideration: See bug 1068652 for discussion.
User impact if declined: Again, see bug 1068652.
Fix Landed on Version: 39.
Risk to taking this patch (and alternatives if risky): Quite low risk. This patch is quite simple and has been in the codebase for two months without an issue.
String or UUID changes made by this patch: None.

See https://wiki.mozilla.org/Release_Management/ESR_Landing_Process for more info.

Comment 6

[Sylvestre Ledru [:Sylvestre]]

Comment on attachment 8584838 [details] [diff] [review]
Bail if OnStartRequest is delivered more than once to imgCacheValidator

Stability improvement and low risk, taking it.

Comment 7

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-esr38/rev/86294b03c5a9