Hi David, >> 1. Initialize JavaThread before calling apply_ergo() in create_vm(). > > That is not likely to be an option - it would likely be far too > disruptive to the initialization sequence.
Agree. Thus I choose 2. > We will have to wait for the tracing experts to have a good look at > this. I'm waiting that the tracing experts join this discussion. Thanks, Yasumasa On 2015/12/23 13:20, David Holmes wrote: > Hi Yasumasa, > > On 23/12/2015 11:49 AM, Yasumasa Suenaga wrote: >> Hi David, >> >> I've added callstack when JVM crashed: >> >> https://bugs.openjdk.java.net/browse/JDK-8145788?focusedCommentId=13880225&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13880225 > > Thanks for that. > >> This crash occurrs in Arguments::apply_ergo() in Threads::create_vm(). >> apply_ergo() calls before JavaThread initialization. >> >> I think that TraceEvent can avoid crash with two approach: >> >> 1. Initialize JavaThread before calling apply_ergo() in create_vm(). > > That is not likely to be an option - it would likely be far too > disruptive to the initialization sequence. > >> 2. Avoid crash at TraceEvent when it is called before JavaThread >> initialization. > > Or don't call it at all. > > We will have to wait for the tracing experts to have a good look at > this. We end up in code that is not expecting to be run before more of > the VM is initialized, so we have to look at what else may be being > assumed and then decide whether to handle the situation or avoid it. > > Thanks, > David > >> >> Thanks, >> >> Yasumasa >> >> >> On 2015/12/22 21:19, David Holmes wrote: >>> On 19/12/2015 1:50 AM, Yasumasa Suenaga wrote: >>>> Hi all, >>>> >>>> I encountered JVM crash when I passed -XX:+EnableTracing. >>>> >>>> I checked core image, it crashed in >>>> EventBooleanFlagChanged::writeEvent() >>>> which is called by Arguments::apply_ergo() because thread had not been >>>> initialized. (JVM seems to log changing GC algorithm to G1.) >>> >>> This seems like a logic error to me - something is trying to happen too >>> early during VM initialization. We need to look at exactly what we are >>> trying to do here, not just work around the crash. >>> >>> David >>> ----- >>> >>>> writeEvent() uses ResourceMark. Default constructor of ResourceMark >>>> uses >>>> ResourceArea in current thread. So ResourceMark in writeEvent() should >>>> pass valid ResourceArea. >>>> >>>> I think this issue is in traceEventClasses.xsl . >>>> However, my environment (GCC 5.3.1 on Fedora23) cannot build it because >>>> -Werror=maybe-uninitialized was occurred. >>>> So I also fixed them together. >>>> >>>> I've uploaded webrev. Could you review it? >>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8145788/webrev.00/ >>>> >>>> I'm jdk9 committer, however I cannot access JPRT. >>>> So I need a sponsor. >>>> >>>> >>>> Thanks, >>>> >>>> Yasumasa >>>>
