[JIRA] (JENKINS-54974) Jenkins does not start due to a deadlock after upgrade from 2.121.2.2 to 2.138.2.2

[arnaud....@gmail.com (JIRA)]

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Arnaud TAMAILLON commented on JENKINS-54974   Re: Jenkins does not start due to a deadlock after upgrade from 2.121.2.2 to 2.138.2.2 Hi Oleg Nenashev (and Daniel Beck as Oleg is stepping back at the moment from Core maintenance).  From my analysis, and some of other issues reported speaking about deadlocks (JENKINS-20988, JENKINS-21034, JENKINS-31622, JENKINS-44564, JENKINS-49038, JENKINS-50663), the issue lies in the DescriptorExtensionList, especially in the way it acquires its load lock. The DescriptorExtensionList getLoadLock method documentation indicates that it is taking part in the real load activity, and that as such, it can lock on *this *rather than on the *singleton Lock *used by ExtensionList. However, many plugins rely on a GlobalConfiguration object, which is acquired through a code similar to the following (which is actually explicitly recommended in GlobalConfiguration documentation). public static SpecificPluginConfig get() { return GlobalConfiguration.all().get(SpecificPluginConfig.class); } (the all() method from the GlobalConfiguration is returning a DescriptorExtensionList) As the configuration for a plugin can be called from many places (initialization of plugin, http requests, ...), it is very easy to have at the same time a DescriptorExtensionList being instantiated, needing in return an ExtensionList, while at the same time, some injection code will have taken the ExtensionList lock and will require DescriptorExtensionList one. Of course, some other uses of DescriptorExtensionList, not related to GlobalConfiguration, can also create the same kind of issues. Taking in to account that the lock is only taken when the list is initialized for the first time (in ensureLoaded()), I would say that removing the override of getLoadLock in DescriptorExtensionList should solve the issue at a very minimal cost. What do you think about this proposal ? Do you see other unintended consequences ? Add Comment   This message was sent by Atlassian Jira (v7.11.2#711002-sha1:fdc329d) -- You received this message because you are subscribed to the Google Groups "Jenkins Issues" group. To unsubscribe from this group and stop receiving emails from it, send an email to jenkinsci-issues+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.