RFR: 8342303: Segfault in update_inherited_vtable: AppCDS, old bytecode, and redefineClasses [v4]

[David Holmes]

On Thu, 31 Oct 2024 21:20:29 GMT, Calvin Cheung <ccheung at openjdk.org> wrote:

>> A simple fix to avoid referencing invalid vtable and itable entires in `InstanceKlass::restore_unshareable_info` if a class is not linked during CDS dump time.
>> 
>> Passed tiers 1 - 4 testing.
>> 
>> ---------
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>
> Calvin Cheung has updated the pull request incrementally with one additional commit since the last revision:
> 
>   @dholmes-ora comments - use Class.forName in all cases

test/hotspot/jtreg/runtime/cds/appcds/jvmti/redefineClasses/OldClassAndRedefineClassApp.java line 39:

> 37:         Instrumentation instrumentation = InstrumentationRegisterClassFileTransformer.getInstrumentation();
> 38:         System.out.println("INFO: instrumentation = " + instrumentation);
> 39:         Class<?> c = ClassLoader.getSystemClassLoader().loadClass("Hello");

Can you use `Class.forName` here too.

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PR Review Comment: https://git.openjdk.org/jdk/pull/21667#discussion_r1825353333