RFR: 8186035: Klass::decode_klass_not_null() asserted on bad oop
stefan.karlsson at oracle.com
Fri Aug 11 09:33:21 UTC 2017
Please review this patch to temporarily remove a failing assert in G1.
The problem is that during initial marking, multiple threads might race
to copy an object and they will all try to mark the new copy if it ends
up in the old gen. In the marking code, there's an assert that the
object should be valid. However, only the thread that won the race to
copying the object is allowed to read the contents of the 'to' copy, and
all other threads might see garbage and could fail on this assert.
The removal of the assert is an interim solution, to get rid of failure
in our testing. I'm working on another fix for this, where only the
winning thread is marking newly copied object. See:
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