I'm using the OpenBMC system (https://github.com/openbmc/openbmc) and
I've tried to enable AppArmor functionality from the 'meta-security'
layer.

To achieve this I've added these strings to my local.conf file:
DISTRO_FEATURES_append = " apparmor"
IMAGE_INSTALL += "apparmor"

The AppArmor functionality was installed to my image, but
unfortunately I've come to this issue:

kernel: AppArmor: AppArmor initialized
kernel: AppArmor: AppArmor Filesystem Enabled
kernel: AppArmor: AppArmor sha1 policy hashing enabled
systemd[1]: systemd 247.3+ running in system mode. (+PAM -AUDIT
-SELINUX -IMA -APPARMOR -SMACK +SYSVINIT -UTMP -LIBCRYPTSETUP -GCRYPT
-GNUTLS -ACL +XZ -LZ4 -ZSTD -SECCOMP +BLKID -ELFUTILS +KMOD -IDN2 -IDN
-PCRE2 default-hierarchy=hybrid)
systemd[1]: Starting AppArmor initialization...
apparmor[113]: Starting AppArmor profiles
apparmor[128]: xargs: invalid option -- 'd'
apparmor[128]: BusyBox v1.33.0 (2021-04-01 10:05:19 UTC) multi-call binary.
apparmor[128]: Usage: xargs [OPTIONS] [PROG ARGS]
apparmor[131]: /lib/apparmor/functions: line 76: echo: write error: Broken pipe
apparmor[131]: /lib/apparmor/functions: line 76: echo: write error: Broken pipe
...
apparmor[131]: /lib/apparmor/functions: line 76: echo: write error: Broken pipe
apparmor[131]: /lib/apparmor/functions: line 76: echo: write error: Broken pipe
apparmor[138]: xargs: invalid option -- 'd'
apparmor[138]: BusyBox v1.33.0 (2021-04-01 10:05:19 UTC) multi-call binary.
apparmor[138]: Usage: xargs [OPTIONS] [PROG ARGS]
apparmor[142]: /lib/apparmor/functions: line 92: echo: write error: Broken pipe
apparmor[142]: /lib/apparmor/functions: line 92: echo: write error: Broken pipe
...
apparmor[142]: /lib/apparmor/functions: line 92: echo: write error: Broken pipe
apparmor[142]: /lib/apparmor/functions: line 92: echo: write error: Broken pipe
apparmor[113]: failed!
systemd[1]: apparmor.service: Main process exited, code=exited, status=1/FAILURE
systemd[1]: apparmor.service: Failed with result 'exit-code'.
systemd[1]: Failed to start AppArmor initialization.
dbus-broker-launch[152]: AppArmor enabled, but not supported. Ignoring.


From the way I see it the problems start from this output:
xargs: invalid option -- 'd'

This error comes from a fact that `xargs` from the `busybox` doesn't
have the `-d` option
(https://git.busybox.net/busybox/tree/findutils/xargs.c)
but this functionality is used in the file:
https://git.yoctoproject.org/cgit/cgit.cgi/meta-security/tree/recipes-mac/AppArmor/files/functions

Once I've discovered it, I started to wonder if I'm doing everything correctly.
Is my issue a simple bug, or AppArmor is not supposed to be run in an
environment like mine?

Best regards,
Konstantin Aladyshev