x/build: consider adding a linux builder with a newer kernel

[mwhudson]

Not entirely sure this is the appropriate form for this request, but well: the PIE internal linking stuff all passes on the builders (and Ubuntu 14.04) but breaks on new-ish linux (e.g. Ubuntu 16.04). I think this is probably a kernel version thing, so can we get a builder with a newer kernel?

[bradfitz]

Newer kernel or newer userspace?

Our builders run a mix of dedicated machines (usually a shell on them from others who admin them), VMs on GCE (where we can control the kernel), and Kubernetes containers (where we can control userspace, but not the kernel).

[mwhudson]

I'm pretty sure it's the kernel, the tests pass in a 16.04 chroot on a 14.04 system and fail in a 14.04 docker container on my 16.04 system (it might be the kernel config vs the kernel version I suppose, but it definitely looks like the kernel).

[bradfitz]

Which test? Did the kernel get stricter, or disable some feature?

[mwhudson]

It's this test #17068. I'm not entirely sure what the change is, am trying to find that out.

[jessfraz]

wait are you using GKE because Container optimized os is 4.4 thats pretty "latest" imho... obviously not "linux-next" or "linux-latest-release" but considering people still run 2.6 (barf) its great

[mwhudson]

I guess it's possible this has been fixed by accident now.

[bradfitz]

All Linux & nacl builds run on GKE now, so use whatever kernel GKE 1.6 uses.

If we need a bleeding-edge or older kernel, we'd need a separate VM image for that.

[jessfraz]

Yeah then it's 4.4