pam_keyinit and common-session

Hi,

We have a "common-session" file in the /etc/pam.d directory which
contains all the modules that should generally be called when
establishing a session: pam_limits, pam_unix, pam_umask, pam_systemd,
pam_env.

We now would like to include pam_keyinit in this file but "this module
should not [...] be invoked by programs like "su""!

Does anyone have an idea how to include pam_keyinit everywhere but not
for "su" and friends? The obvious answer would be to explicitly include
it in all the other files in /etc/pam.d. Another idea would be to put
"pam_keyinit" in "common-session" and then have a separate
"common-session-su" (or "common-session-nokeyinit") which does not have
pam_keyinit.

But I'm hoping for a better solution.

Thanks,

Josef