[jdk17] RFR: 8266889: [macosx-aarch64] Crash with SIGBUS in MarkActivationClosure::do_code_blob during vmTestbase/nsk/jvmti/.../bi04t002 test run [v2]

[David Holmes]

On Tue, 13 Jul 2021 10:13:39 GMT, Anton Kozlov <akozlov at openjdk.org> wrote:

>> The change adds W^X transition in RawMonitor family of functions, fixing the crash. RawMonitor functions are treated specially, so W^X transition is not inserted automatically. A better fix would be in .xml description for entries generation, but for now it is too risky. I hope to get this fixed in 17 in the simplest way and do re-work in the 18. This change is still 100% correct for the reported bug.
>> 
>> Verified by: 
>> 
>> jtreg -vmoption:-XX:+AssertWXAtThreadSync test/hotspot/jtreg/vmTestbase/nsk/jvmti/scenarios/bcinstr/BI04/bi04t002
>
> Anton Kozlov has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Subset of RawMonitor; comments added

Seems fine to address current problem, but we need a much clearer, more systematic approach to handling this (and enabling others to easily understand when and why it is needed).

Thanks,
David

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Marked as reviewed by dholmes (Reviewer).

PR: https://git.openjdk.java.net/jdk17/pull/244