577398 - ContentProcessParent doesn't remove itself as an observer

Status: RESOLVED DUPLICATE of bug 621386

(Core :: IPC, defect)

Description

[Josh Matthews [:jdm]]

79                 if (NS_SUCCEEDED(obs->AddObserver(parent, "xpcom-shutdown",
80                                                   PR_FALSE))) {
...
82                     nsCOMPtr<nsIPrefBranch2> prefs 
83                         (do_GetService(NS_PREFSERVICE_CONTRACTID));
84                     if (prefs) {  
85                         prefs->AddObserver("", parent, PR_FALSE);
86                     }
87                 }
88                 obs->AddObserver(
89                   parent, NS_IPC_IOSERVICE_SET_OFFLINE_TOPIC, PR_FALSE); 

102 void
103 ContentProcessParent::ActorDestroy(ActorDestroyReason why)
...
110         obs->RemoveObserver(static_cast<nsIObserver*>(this), "xpcom-shutdown");

Dunno how bad it is, but in the event of a crashed content process we'd end up with the pref observers keeping the actual parent object around until app shutdown.  We should probably fix this up.

Comment 1

[Josh Matthews [:jdm]]

Actually, the pref observer is cleared on xpcom-shutdown.  However, I'm fairly certain that this won't happen if the content process dies prematurely for any reason.

Comment 2

[Josh Matthews [:jdm]]

Attachment: Remove all ContentParent observers on ActorDestroy.

Comment 3

[Josh Matthews [:jdm]]

This is handled by bug 621386.