Intermittent SEGV running ParallelGC

We are seeing intermittent SEGVs running specjbb2013 with both aarch64 jdk8 port (built from ssh://enevill@hg.openjdk.java.net/aarch64-port/jdk8u) and jdk9 (built from ssh://enevill@hg.openjdk.java.net/jdk9/hs-comp).

This crash only occurs on Partner X hardware.

Prebuilt binaries which exhibit the problem may be downloaded from

http://openjdk.linaro.org/releases/jdk8u-server-release-1509.tar.xz

http://openjdk.linaro.org/releases/jdk9-server-release-1508.tar.xz

A sample hs_err log is attached below.

This only occurs with UseParallelGC so it happens by default with jdk8 but only happens with jdk9 with -XX:+UseParallelGC

The frequency of the crash is about one in 10 runs.

The command used to invoke specjbb2013 is

java -Xmx50g -Xms50g -Xmn40g -Dspecjbb.forkjoin.workers=48 -jar specjbb2013.jar -m COMPOSITE

(note: if using jdk9 you also need -XX:+UseParallelGC to observe the problem)