The allowlist was derived from crosvm's gpu_common + gpu_device seccomp
policies, but those are applied after process startup. systemd applies
the filter before exec, so process lifecycle (execve, wait4, arch_prctl,
set_tid_address), capability management (capget, capset), and socket
server (bind, listen, accept4, socketpair) syscalls are also needed.
Also create a shader cache directory at /run/vmsilo/<name>/gpu/cache and
set __GL_SHADER_DISK_CACHE_PATH so the GPU device backend doesn't fail
trying to create /home for shader cache in the sandboxed mount namespace.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>