RFR: 8342303: Segfault in update_inherited_vtable: AppCDS, old bytecode, and redefineClasses [v8]

[Calvin Cheung]

On Thu, 7 Nov 2024 05:26:07 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.
>> 
>> ---------
>> ### Progress
>> - [ ] Change must be properly reviewed (1 review required, with at least 1 [Reviewer](https://openjdk.org/bylaws#reviewer))
>> - [x] Change must not contain extraneous whitespace
>> - [x] Commit message must refer to an issue
>> 
>> 
>> 
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>> `$ git checkout pull/21667`
>> 
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>
> Calvin Cheung has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 10 additional commits since the last revision:
> 
>  - fix some tests failures due to jdk/test/lib/compiler/InMemoryJavaCompiler class not found
>  - Merge branch 'master' into 8342303-old-class-redefineClasses
>  - remove extra import and "@build" entries
>  - @coleenp comment - use RedefineClassHelper
>  - convert remaining getSystemClassLoader().loadClass() to Class.forName()
>  - @dholmes-ora comments - use Class.forName in all cases
>  - avoid using getContextClassLoader()
>  - add more tests and simplify OldClassAndRedefineClass.java
>  - new fix
>  - 8342303: Segfault in update_inherited_vtable: AppCDS, old bytecode, and redefineClasses

Thanks for the reviews!

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PR Comment: https://git.openjdk.org/jdk/pull/21667#issuecomment-2462942202