4.3 KiB
Native macOS guest on existing Docker infrastructure — 2026-10-03
Result: real macOS Recovery booted under software emulation, but the bounded experiment did not reach an installed guest or execute the native tests. This is not a passing CI result or a verified workflow recipe.
Source and execution boundary
- Dockur source:
16a5b470cdd601bae8b05b02d748d7edfb36c12e. - Local environment: existing ARM64 Docker Desktop, linux/amd64 container translation, x86_64 QEMU guest with TCG. This does not establish the runtime or resources of the upstream Ubuntu-x64 runner.
- Guest settings:
VERSION=14,MANUAL=N,KVM=N,NETWORK=slirp, 4 GiB guest RAM, two vCPUs, 64 GiB sparse guest disk. Container memory was limited to 6 GiB. - Container inspection:
Privileged=false,CapAdd=null,Devices=[], ordinary bridge network. Diagnostic ports were published only on localhost. No runner registration, host configuration, device passthrough or new secret was requested. - Candidate archive: clean application/test source at
1164c26846686c1912fd1816cd06de80352e9504, SHA-25630796a27c75792ab87d23dd4c4db991b426d9c55a0e7dc3d4dc45c41056846e1. It was not executed in the guest.
Observed boundary failure
The container built and downloaded Apple's Recovery image. Recovery mounted its installation-state share, found Sonoma's startosinstall, and passed the upstream unattended preflight. Native sw_vers and uname output identified:
ProductVersion: 14.6.1
BuildVersion: 23G93
Darwin Kernel Version 23.6.0 ... RELEASE_X86_64 x86_64
The first target-selection attempt found no writable disk. Both virtio and SATA trials subsequently exposed diskutil failure: it could not use the DiskManagement framework. Its diagnostic listed unavailable DiskArbitration/single-user mode as a possible cause; that cause was not independently established. SATA also exposed an independent missing io2 QEMU object, corrected through an ordinary QEMU argument without host capabilities.
The pinned Recovery patch replaces an early rc.cdrom.sh block, before normal daemon startup, with a blocking exec launch.sh. One final causal trial changed only this padded bootstrap to launch the installer in the background. Its old/new bootstrap SHA-256 values were 73fd171ea4c889f9946f04d6866047fedd417a69a241b3e84db469c13975d897 and c5fc86f95e9c65dd7dc59536911c81c96928d4f9541b63121c22cad5690f3582. The launch script also waited for actual diskutil list physical success before the unchanged writable-disk/size guards and captured diagnostics after mounting the share.
That trial still recorded 12 completed native diskutil failures and an incomplete thirteenth attempt:
Unable to run because unable to use the DiskManagement framework.
Common reasons include, but are not limited to, the DiskArbitration
framework being unavailable due to being booted in single-user mode.
[exit 1]
There was no successful disk enumeration, selected installation target, target erase or startosinstall invocation. The background change did not establish a working bootstrap; the remaining daemon/framework cause is unresolved. This result does not prove that macOS under TCG on Ubuntu is impossible.
End state and evidence
Final container: c4d5b83f5199063df75d43236d610ef9b71c3b39c14b80a649b0e904d13e87c8. It started at 10:46:24.987543461 UTC; the authorized final boot boundary was start plus 16 minutes. It was stopped at 11:02:33.810090465 UTC: Running=false, ExitCode=143, OOMKilled=false. No experiment container remained running.
Raw evidence is retained locally under /private/tmp/meeting-assistant-macos-guest-proof-20261003/runs/c4d5b83f5199/: guest-disk-platform.log, physical-disks-ready.log, recovery-install.log, their capture metadata, and end-container-inspect.json/end-state.json. Metadata identifies the full container ID, actual start time, capture time and log SHA-256; earlier flat logs are historical and were not treated as success in this run.
No guest SSH session, official .NET/Apple CLT bootstrap, Swift build or TRX result was obtained. The application's workflow, production runtime and tests were not changed by this experiment. Native Ubuntu CI remains open; local Mac qualification is recorded separately in the CI evidence.