[jdk8u-dev] RFR: 8065895: Synchronous signals during error reporting may terminate or hang VM process

[Zhengyu Gu]

I would like to backport this patch to openjdk8u for parity with Oracle 
8u321.

Bug: https://bugs.openjdk.java.net/browse/JDK-8065895
jdk9 patch: [http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/6bfc40057b3f](https://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/6bfc40057b3f)


jdk9 patch does not apply cleanly. There is only one conflict in 
`debug.cpp`, due to line shifts.

Original cod review thread: https://mail.openjdk.java.net/pipermail/jdk8u-dev/2021-July/014133.html
and it has been reviewed by the author @stuefe (not a jdk8u reviewer)

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Commit messages:
 - 8065895: Synchronous signals during error reporting may terminate or hang VM process

Changes: https://git.openjdk.java.net/jdk8u-dev/pull/39/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk8u-dev&pr=39&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8065895
  Stats: 199 lines in 8 files changed: 142 ins; 3 del; 54 mod
  Patch: https://git.openjdk.java.net/jdk8u-dev/pull/39.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk8u-dev pull/39/head:pull/39

PR: https://git.openjdk.java.net/jdk8u-dev/pull/39