AFAIK there is no such feature as linux.
I think this should be system-linux
linux and freebsd requirement tags were used by other projects like XRay.
I'm not sure if those tests are skipped or not. I would really appreciate any feedback on this.
The relevant test infra code segment is this - I think:
elif platform.system() == 'Linux': features.add('system-linux')
BTW on my system (Ubuntu 18.04), the patched tests were marked UNSUPPORTED.
After the fix, they all PASSed.