The socat suite is sleep-bound and slow run serially. Drive it through
parallel-make-check.py as ~6 shards per CPU, 2 running per CPU at once: each
shard runs a round-robin slice of the tests in its own bwrap network
namespace (so parallel shards don't collide on ports) and its own build-dir
copy. The work is almost all waiting, so the oversubscription just overlaps
the waits.
Install bubblewrap so the netns isolation actually happens (without it the
runner silently shares one namespace and the shards collide). Each fresh
netns is IPv4-loopback only, so re-create IPv6 loopback (CAP_NET_ADMIN) for
the ::1 / dual-stack tests, and add non-loopback placeholders (fc00::1,
192.0.2.1) so glibc's AI_ADDRCONFIG still returns both families - without
them socat's getaddrinfo fails on numeric non-loopback addresses, e.g. the
multicast tests. Relax the AppArmor unprivileged-userns restriction so the
bwrap netns + CAP_NET_ADMIN work on ubuntu-24.04.
Juliusz Sosinowicz
f2fa741bad