Kernel Mode
Kernel Mode
Kernel mode is systemg operating below the user session: as the machine's service supervisor, as a container's init process, and against kernel enforcement and observation interfaces.
The sysg supervisor is a userspace program. No systemg code executes in ring 0. "Kernel mode" names the family of capabilities where the kernel — not the user session — is the counterparty.
The capability family
| Capability | What executes where | Status |
|---|---|---|
| System mode | Userspace, root; drops privileges per service | Linux and macOS (--sys) |
| Container-init | Userspace, PID 1 duties | Linux (sysg init) |
| Kernel-enforced sandboxing | Kernel enforces; sysg configures | Linux, schema v3 |
| Kernel-assisted observation | pidfd | Linux 5.3+ |
Mode parity contract
User mode and system mode are peers: identical commands, identical output
shapes, identical diagnostics wherever a capability is supported — and a
refusal, never a warning that proceeds, where it is not. The parity contract
is enforced by the parity-* use-case lanes, which run every scenario as a
real non-root user and as root --sys on both glibc and Alpine/musl
runtimes.
Security
See Security & audits for the threat model and the per-milestone audit records in the repository.