On Wed, 28 Jul 2021 14:22:07 GMT, Thomas Stuefe <stu...@openjdk.org> wrote:
>> If a thread is attaching via JNI and has not yet created its Thread object >> it can be caught in a ThreadSnapshot during a thread dump (VM_DumpThreads) >> of all threads**, and the threadObj() will be NULL, so we can't pass it to >> get_thread_status(). >> >> ** JMM dumpThreads API >> >> The initial fix simply checks for a NULL threadObj() and reports thread >> status NEW in that case. >> >> Alternatively we could filter the attaching thread out completely in >> VM_DumpThreads::doit by expanding: >> >> if (jt->is_exiting() || >> jt->is_hidden_from_external_view()) { >> // skip terminating threads and hidden threads >> continue; >> } >> >> to also check jt->is_attaching_via_jni(). >> >> Note that higher-level code already filters out ThreadSnapshots with NULL >> threadObj() anyway so we could go either way. >> >> Testing: manual hacks - see bug report. >> - tier 1-3 sanity testing >> >> Thanks, >> David > > This looks good to me. > > ..Thomas Thanks for the reviews @tstuefe and @dcubed-ojdk ! ------------- PR: https://git.openjdk.java.net/jdk/pull/4921