RFR: JDK-8319633: runtime/posixSig/TestPosixSig.java intermittent timeouts on UNIX [v2]

[David Holmes]

On Thu, 23 Nov 2023 16:49:18 GMT, Joachim Kern <jkern at openjdk.org> wrote:

>> Every 1-2 weeks we run into timeouts when running jtreg test runtime/posixSig/TestPosixSig.java on UNIX.
>> The thread stack shows that we are in line 54 of TestPosixSig.java.
>> 
>> The reason is the following: The test registers a new dummy signal handler for SIGILL, without delegating the task to the previous handler in the chain. In case the VM then calls a Java method marked as not-entrant at least on PPC64 a SIGILL is raised. Because this is not handled by the registered handler the SIGILL will happen again and again in an endless recursion.
>> One solution would be to add a delegation to the hotspot signal handler, which is the previous handler in the chain.
>
> Joachim Kern has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix linux build error

Does the failure only happen when running with Xcomp? If so we could just require it to not run then. Otherwise the chaining seem reasonable, but needs a change I think.

Thanks

test/hotspot/jtreg/runtime/posixSig/libTestPsig.c line 48:

> 46:     sigemptyset(&act.sa_mask);
> 47:     act.sa_flags = SA_SIGINFO;
> 48:     int retval = sigaction(val, &act, &oact);

This will still leave a window where the new handler is installed but not yet chained. Better to use one `sigaction` to read the old handler, then install the new one.

-------------

Changes requested by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/16797#pullrequestreview-1747233325
PR Review Comment: https://git.openjdk.org/jdk/pull/16797#discussion_r1403886177