A Grok sandbox exit 0 does not mean Landlock applied
grok --sandbox devbox inspect --json exited 0. Stderr was empty. The JSON it printed had no sandbox field. The same run appended a row to sessions/sandbox-events.jsonl under the grok home:
event_type: ApplyFailed
profile: devbox
platform: linux/landlock
enforced: false
error: Landlock not available. Requires Linux kernel 5.13+ with Landlock enabled.
/sys/kernel/security/landlock was not on this host. /sys/kernel/security was. uname -r was 7.0.14-6-pve. The event sentence is not a version check. A kernel newer than 5.13 can still leave that sysfs node absent. /proc/config.gz and the matching /boot/config-* file were not there, so this note does not say which kernel option is missing. It says the node Grok’s own error names as the requirement was not present, and the command that asked for the profile still returned success.