Add support for s390x seccomp

[nealef]

s390x fails basic checks because it has no support for seccomp. This PR adds s390x as a supported architecture.

If you need a s390x host for use in your CI setup let me know as I have access to Z resources that could be used.

[elasticmachine]

Pinging @elastic/es-core-infra

[tvernum]

Hi @nealef

In the PR guidelines we note that only accept PRs for Operating Systems that we support:

If submitting code, have you checked that your submission is for an OS that we support?

That really should say "OS and architecture" as we only support x86_64 (and not System/390).

We appreciate you offer to help with CI, but it's more complex than that.
If we choose to support a particular platform, then we take that seriously, and have a suite of tests that we run, and our team ensures that every Elasticsearch releases works correctly on that platform. Adding it to CI is one part of that, but it also means we need to spend time investigating failures on that platform, and making sure performance is acceptable, etc.

If we do not support the platform then we generally will not merge PRs because we cannot guarantee that the change works, and will continue to work in future releases and we aren't prepared to have code in the repository that we cannot maintain (because we cannot test it).

I've assigned this to the team that is responsible for this area of the code, but I want to warn you that it is unlikely to be merged.

[nealef]

I've assigned this to the team that is responsible for this area of the code, but I want to warn you that it is unlikely to be merged.

I understand the philosophy and can only hope that this fix is so minor that it may make it through. I am using with OpenShift and it will not run without passing this bootstrap check - even if I tell it to ignore as it reports that owing to some network configuration in place the check cannot be ignored.

[rjernst]

@nealef As Tim explained, we don't want to feign support for a platform we do not officially support. The concern of merging any change, even a simple one, is that followup changes may be necessary to get ES working on that unsupported platform, which can quickly snowball. Given that stance, I hope you don't mind that I close this issue.

With that said, seccomp support is not required to run Elasticsearch. If you open a thread in our discuss forum, we can help you investigate why Elasticsearch is failing to start.

[nealef]

Yes I do understand. The seccomp stuff is only required when running as part of openshift. I note that RedHat/IBM are now officially supporting OpenShift 4.x on Z (s390x) so they will also be facing this issue (and possibly solving it the same way I did as I provided them with my patch). Hopefully, they'll decide they need to get official support from you guys and provide you with some resources to make it part of the product.