Chris & David, JVMTI_ERROR_WRONG_PHASE problem is complicated and requires significant work probably on both JDWP and JVMTI side. Serguei plan to do it as a part of JDK-8134103 and not for JDK 9.
So yes, we can close this one as a dup of JDK-8134103 - it has the same root cause and should be addressed as the part of JDK-8134103 (particularly, we have to cleanup ignore_vm_death logic) But the crash is observed only once in a nightly, so my intention is to save us a bit of time next time when this situation happens. i.e. before the changes we get JVMTI_ERROR_WRONG_PHASE message and *crash*, after the changes we get JVMTI_ERROR_WRONG_PHASE message and AGENT_ERROR_INTERNAL message. -Dmitry On 2016-08-29 09:43, Chris Plummer wrote: > On 8/28/16 6:14 PM, David Holmes wrote: >> On 27/08/2016 7:35 AM, Chris Plummer wrote: >>> Hi Dmitry, >>> >>> Although the fix is addressing the specific issue described in the bug, >>> what about the general issue of referencing gdata after a call to >>> cbEarlyVMDeath(). Do more references to gdata need to be protected? >>> >>> Also, is there the possibility of a multi-threading race condition here? >>> Could gdata be cleared by another thread after it is checked? >> >> Certainly. This really isn't fixing anything just adding a bailout >> check before the crashing code. We can still crash and not be any the >> wiser as to why. >> >> Not sure I really see the point of doing this instead of closing this >> as a dup of JDK-8134103 and fixing things properly. > It it correct to say that Dmitry is fixing a bug exposed by JDK-8134103, > or that he is temporarily working around something that is not a true > bug, but is indirectly caused by JDK-8134103. I'm not sure, but the > answer will dictate the correct course of action here. > > Chris >> >> David >> >>> thanks, >>> >>> Chris >>> >>> On 8/26/16 4:00 AM, Dmitry Samersoff wrote: >>>> Everybody, >>>> >>>> Please review the fix. >>>> >>>> http://cr.openjdk.java.net/~dsamersoff/JDK-8163994/webrev.02/ >>>> >>>> *Problem* >>>> >>>> Under some circumstances, when JVMTI_ERROR_WRONG_PHASE(112) is >>>> received, >>>> jvmtiAllocate could be called after call to cbEarlyVMDeath. >>>> >>>> cbEarlyVMDeath set gdata->jvmti to NULL, so jvmtiAllocate crashes. >>>> >>>> The problem appears only once in nightly testing and I was not able to >>>> reproduce it locally. >>>> >>>> *Solution* >>>> >>>> Guard added to jvmtiAllocate to get meaningful error message instead of >>>> crash. >>>> >>>> These fix doesn't fix root cause - JVMTI_ERROR_WRONG_PHASE problem is >>>> going to be addressed under JDK-8134103. >>>> >>>> -Dmitry >>>> >>> > -- Dmitry Samersoff Oracle Java development team, Saint Petersburg, Russia * I would love to change the world, but they won't give me the sources.
