--readonly ran `chmod -R a-w` over the workspace after copying, but
every banger guest boots as root, and root bypasses DAC mode checks.
So a user running `vm workspace prepare ... --readonly` got the
mode bits set to 0444 but `echo x >> file` in the guest still
succeeded. The flag promised enforcement it couldn't deliver.
The feature also doesn't match the product model: workspaces are
prepared precisely so the guest CAN edit them, and `workspace
export` exists to pull those edits back as a patch. A
"read-only workspace" contradicts that loop.
Removed:
- CLI flag `--readonly` on `vm workspace prepare`
- api.VMWorkspacePrepareParams.ReadOnly field
- model.WorkspacePrepareResult.ReadOnly field
- daemon chmod dispatch in prepareVMWorkspaceGuestIO
- smoke scenario pinning the (advisory) mode-bit behavior
- misleading "exportbox-readonly" VM name in an unrelated export
test (the test is about not mutating the real git index;
renamed to exportbox-noindex-mutation)
If real enforcement becomes a user need later, the right primitive
is `chattr +i` (immutable bit — root CAN'T write) or a ro bind-mount.
Reintroducing a new flag is cheaper than debugging what the current
one actually guarantees.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Thales Maciel
235758e5b2