RFR: 8353117: Crash: assert(id >= ThreadIdentifier::initial() && id < ThreadIdentifier::current()) failed: must be reasonable)

[David Holmes]

On Mon, 31 Mar 2025 18:15:39 GMT, Patricio Chilano Mateo <pchilanomate at openjdk.org> wrote:

> Please review the following fix. For the attaching thread case we are incorrectly setting the `_monitor_owner_id` after `Threads::add()` is called, i.e after the attaching thread becomes visible through a ThreadsListHandle. So if another thread calls `Threads::owning_thread_from_monitor()` in between these events and iterates through all JavaThreads looking for the owner of a given monitor, we might find this attaching thread still with a `_monitor_owner_id` of 0.
> I corrected the ordering and improved verification checks. Tested in mach5 tiers1-5.
> 
> Thanks,
> Patricio

That seems fine to me. Thanks for fixing.

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24336#pullrequestreview-2731738289