field `mountType` must be %#q or %#q for krunkit driver, got

Error message

field `mountType` must be %#q or %#q for krunkit driver, got %#q

What it means

The krunkit driver only supports virtiofs and revsshfs as mount types. validateConfig rejects any other value of `mountType` because libkrun-based VMs cannot use Lima's other mount mechanisms. The error reports the allowed values and the offending value using %#q formatting.

Source

Thrown at pkg/driver/krunkit/krunkit_driver_darwin_arm64.go:235

	if err != nil {
		return err
	}
	if macOSProductVersion.LessThan(*semver.New("13.0.0")) {
		return errors.New("krunkit driver requires macOS 13 or higher to run")
	}
	if cfg.Arch != nil && !limatype.IsNativeArch(*cfg.Arch) {
		return fmt.Errorf("unsupported arch: %#q (krunkit requires native arch)", *cfg.Arch)
	}
	if _, err := exec.LookPath(vmType); err != nil {
		return errors.New("krunkit CLI not found in PATH. Install it via:\nbrew tap slp/krun\nbrew install krunkit")
	}
	// Also check if krunkit version >= 1.2.1 because of the vsock forwarder feature
	if err := checkKrunkitVersion(); err != nil {
		return err
	}

	if cfg.MountType != nil && (*cfg.MountType != limatype.VIRTIOFS && *cfg.MountType != limatype.REVSSHFS) {
		return fmt.Errorf("field `mountType` must be %#q or %#q for krunkit driver, got %#q", limatype.VIRTIOFS, limatype.REVSSHFS, *cfg.MountType)
	}

	if cfg.TPM != nil && *cfg.TPM {
		return errors.New("field `tpm` is not supported in krunkit driver")
	}

	if cfg.NestedVirtualization != nil && *cfg.NestedVirtualization {
		if macOSProductVersion.LessThan(*semver.New("15.0.0")) {
			return errors.New("nested virtualization requires macOS 15 or newer")
		}
	}

	if cfg.OS != nil && *cfg.OS == limatype.WINDOWS {
		return errors.New("currently Windows guest OS is only supported on QEMU")
	}

	return nil
}

View on GitHub (pinned to dd909d0973)

Solutions

Change `mountType` to `virtiofs` (recommended for krunkit)
Or set `mountType: revsshfs` if SSHFS-based mounting is required
Remove the `mountType` field entirely so Lima defaults to a driver-supported value

Example fix

// before (lima.yaml)
mountType: 9p
// after
mountType: virtiofs

Defensive patterns

Strategy: validation

Validate before calling

mountType := "virtiofs" // allowed: virtiofs | revsshfs for krunkit
if mt != "virtiofs" && mt != "revsshfs" {
    return fmt.Errorf("mountType %q unsupported for krunkit", mt)
}

Prevention

Use virtiofs or revsshfs in any krunkit config
Do not copy 9p-based QEMU configs to krunkit unchanged
Run `limactl validate lima.yaml` before start

When it happens

Trigger: Setting `mountType: 9p` (or any value other than virtiofs/revsshfs) in lima.yaml for an instance whose vmType is krunkit, then running limactl validate or limactl start.

Common situations: Reusing a QEMU-oriented config (QEMU supports 9p) with krunkit; typos like `virtio-fs` or `sshfs`; older templates with removed mount types.

Related errors

AI-assisted analysis of lima-vm/lima@dd909d0973 (2026-09-01). Data as JSON: /api/errors/947710d68ddca438. Report an issue: GitHub.