RFR: 8265292: [macos_aarch64] java/foreign/TestDowncall.java crashes with SIGBUS [v2]

[Anton Kozlov]

On Tue, 11 May 2021 15:09:25 GMT, Anton Kozlov <akozlov at openjdk.org> wrote:

>> Please review a fix for the intermittent crash. It is caused by a mistake in the ProgrammableInvoker::invoke_native, the wrong order of W^X and JavaThread state transition. We need WXExec since we are about to call a generated stub. But we need to switch to WXExec only after JavaThread state change. The thread state change may trigger a safepoint, that would need to do bookkeeping in the codecache (MarkActivationClosure::do_code_blob from the bug). So the fix is to change JavaThread state first, then change WX.
>> 
>> The fix was verified with the help of https://bugs.openjdk.java.net/browse/JDK-8266742. The new check catches all test failures reported by 8265292, 8265183, 8265182. I've verified tests pass after the fix with that new check enabled.
>
> Anton Kozlov has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add comments

OK, thanks! I still don't think there is something needs fixing, but a consensus is necessary, I agree.

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PR: https://git.openjdk.java.net/jdk/pull/3921