[jdk22u] RFR: 8329528: G1 does not update TAMS correctly when dropping retained regions during Concurrent Start pause

[Thomas Schatzl]

On Wed, 17 Apr 2024 06:50:20 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

>> Hi all,
>> 
>>   please review this backport for https://bugs.openjdk.org/browse/JDK-8329528; it applies cleanly apart from the hunk now in `inline void HeapRegion::note_start_of_marking()` - in jdk23 this method moved from there to concurrent marking code, although the change itself is the same.
>> 
>> This issue causes random crashes in G1. There is no workaround.
>> 
>> The change baked in jdk23 for a week or so, with no issues. Risk is little at this point as the patch is small and well understood, and there is a regression test.
>> 
>> Testing: gha, tier1-5
>
> Marked as reviewed by ayang (no project role).

Thanks @albertnetymk @chrishegarty for your reviews. Now applying for push approval.

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PR Comment: https://git.openjdk.org/jdk22u/pull/145#issuecomment-2060909216