During testing, I found that attach-device and attach-disk occasionally triggered spurious APPARMOR_DENIED messages in the host kernel (possibly related to the guest kernel trying to poll it). Whenever I saw these messages, the guest was always able to access the disk (eg 'sudo fdisk -l /dev/...). It is possible that the host kernel isn't up to date on the logging the split second after apparmor_parser exits. This could possibly be fixed if libvirt slept for a second in after calling virt-aa-helper.
During testing, I found that attach-device and attach-disk occasionally triggered spurious APPARMOR_DENIED messages in the host kernel (possibly related to the guest kernel trying to poll it). Whenever I saw these messages, the guest was always able to access the disk (eg 'sudo fdisk -l /dev/...). It is possible that the host kernel isn't up to date on the logging the split second after apparmor_parser exits. This could possibly be fixed if libvirt slept for a second in after calling virt-aa-helper.