JDK-8322163: runtime/Unsafe/InternalErrorTest.java fails on Alpine after JDK-8320886

[MBaesken]

We notice failures/crashes on Alpine Linux, maybe after JDK-8320886.
test runtime/Unsafe/InternalErrorTest.java crashes on Alpine (works fine on other test OS/CPU platforms) :

#
# SIGSEGV (0xb) at pc=0x00007fd3c080064f, pid=7075, tid=7161
#
# JRE version: OpenJDK Runtime Environment (23.0) (build 23-internal-adhoc.jenkinsi.jdk)
# Java VM: OpenJDK 64-Bit Server VM (23-internal-adhoc.jenkinsi.jdk, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# C [ld-musl-x86_64.so.1+0x5464f] memset+0xa7
#

Looks like the Alpine memset triggers unexpected SIGSEGV (not the expected SIGBUS). So we switch to a loop instead of memset. However I noticed that on Linux aarch64 the test starts to fail when the loop is used instead of the memset, so I keep the old coding on this platform .

---

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Issue

• JDK-8322163: runtime/Unsafe/InternalErrorTest.java fails on Alpine after JDK-8320886 (Bug - P3)

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)
• Christoph Langer (@RealCLanger - Reviewer)

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[TheRealMDoerr]

I think it's very bad to let C code run into signals (SIGBUS or SIGSEGV) regardless of your change. In addition, the signal handler just skips the faulting instruction and continues with the next one. That does not yield defined behavior!
(On linux aarch64, the new loop doesn't work, because gcc generates an strb instruction with internal address increment. The signal prevents both, the store and the address increment, so we end up in an endless loop.)
If we only want to do a simple fix for Alpine x86_64, I suggest to use the new code only on that platform. It's bad for other platforms, too, but it works because it gets tested. (Doesn't mean that it will always work with every compiler. So, there's still room for improvement.)

[MBaesken]

Hi Martin,

If we only want to do a simple fix for Alpine x86_64, I suggest to use the new code only on that platform.

I adjusted the code so that the loop is only done on Alpine/MUSL .

[TheRealMDoerr]

I think this is an acceptable solution.

[openjdk]

@MBaesken This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8322163: runtime/Unsafe/InternalErrorTest.java fails on Alpine after JDK-8320886

Reviewed-by: mdoerr, clanger

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At the time when this comment was updated there had been 7 new commits pushed to the master branch:

• c53f845: 8322539: Parallel: Remove duplicated methods in PSAdaptiveSizePolicy
• 84c2379: 8320139: [JVMCI] VmObjectAlloc is not generated by intrinsics methods which allocate objects
• 3b908c4: 8319795: Static huge pages are not used for CodeCache
• 1802601: 8293623: Simplify G1ConcurrentRefineThreadControl
• 6de23bf: 8322418: Problem list gc/TestAllocHumongousFragment.java subtests for 8298781
• aff659a: 8322538: remove fatal from JVM_VirtualThread functions for !INCLUDE_JVMTI
• 05745e3: 8319548: Unexpected internal name for Filler array klass causes error in VisualVM

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[RealCLanger]

Sounds like a reasonable fix.

[MBaesken]

Hi Martin and Christoph, thanks for the reviews !

/integrate

[openjdk]

Going to push as commit 1230853.
Since your change was applied there have been 8 commits pushed to the master branch:

• dce7a57: 8321683: Tests fail with AssertionError in RangeWithPageSize
• c53f845: 8322539: Parallel: Remove duplicated methods in PSAdaptiveSizePolicy
• 84c2379: 8320139: [JVMCI] VmObjectAlloc is not generated by intrinsics methods which allocate objects
• 3b908c4: 8319795: Static huge pages are not used for CodeCache
• 1802601: 8293623: Simplify G1ConcurrentRefineThreadControl
• 6de23bf: 8322418: Problem list gc/TestAllocHumongousFragment.java subtests for 8298781
• aff659a: 8322538: remove fatal from JVM_VirtualThread functions for !INCLUDE_JVMTI
• 05745e3: 8319548: Unexpected internal name for Filler array klass causes error in VisualVM

Your commit was automatically rebased without conflicts.

[openjdk]

@MBaesken Pushed as commit 1230853.

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