systemtap-4.3-4.el8 doesn't seem to cope with secureboot on rhel-8.3:

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[root@localhost ~]# stap --trust-servers=ssl,signer,all-users,no-prompt --use-server=$SERVER_IP:$SERVER_PORT
Adding trust in the following servers as an SSL peer for all users and as a module signer for all users
   host=unknown address=127.0.0.1 port=33645 sysinfo="unknown" version=unknown certinfo="unknown"
[root@localhost ~]# stap --use-server=$SERVER_IP:$SERVER_PORT -v -e 'probe oneshot { log("hey") }'
Using a compile server.
Pass 1: parsed user script and 485 library scripts using 452652virt/85596res/12876shr/72180data kb, in 160usr/40sys/227real ms.
Pass 2: analyzed script: 1 probe, 2 functions, 0 embeds, 0 globals using 454236virt/87244res/12948shr/73764data kb, in 10usr/0sys/7real ms.
Pass 3: translated to C into "<server>/stap000000/stap_7422abb93e345a17b57111389bdf1c69_1121_src.c" using 454372virt/87244res/12948shr/73900data kb, in 0usr/0sys/0real ms.
Pass 4: compiled C into "stap_7422abb93e345a17b57111389bdf1c69_1121.ko" in 12570usr/2020sys/14743real ms.
Server: No matching machine owner key (MOK) available on the server to sign the
 module.
Server: The server has no machine owner key (MOK) in common with this
system. Use the following command to import a server MOK into this
system, then reboot:

        mokutil --import signing_key.x509
Passes: via server  host=unknown address=127.0.0.1 port=33645 sysinfo="unknown" version=unknown certinfo="unknown" using 384836virt/17476res/15136shr/1740data kb, in 50usr/10sys/16499real ms.
Passes: via server failed.  Try again with another '-v' option.
The kernel on your system requires modules to be signed for loading.
The module created by compiling your script must be signed by a systemtap compile-server.  [man stap-server]
--use-server was automatically selected in order to request compilation by a compile-server.
[root@localhost ~]#
[root@localhost ~]# mokutil --import signing_key.x509
input password: 
input password again: 
[root@localhost ~]# 
[root@localhost ~]# reboot 
Connection to 192.168.0.171 closed by remote host.
Connection to 192.168.0.171 closed.
$ 

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Reboot; Key successfully enrolled; Reboot
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[root@localhost ~]# service stap-server start
Redirecting to /bin/systemctl start stap-server.service
[root@localhost ~]# netstat -tlp | grep stap
tcp6       0      0 [::]:32901              [::]:*                  LISTEN      1730/stap-serverd   
[root@localhost ~]# SERVER_PORT=32901
[root@localhost ~]# SERVER_IP=127.0.0.1
[root@localhost ~]# stap --trust-servers=ssl,signer,all-users,no-prompt --use-server=$SERVER_IP:$SERVER_PORT
Adding trust in the following servers as an SSL peer for all users and as a module signer for all users
   host=unknown address=127.0.0.1 port=32901 sysinfo="unknown" version=unknown certinfo="unknown"
[root@localhost ~]# stap --use-server=$SERVER_IP:$SERVER_PORT -v -e 'probe oneshot { log("hey") }'
Using a compile server.
Pass 1: parsed user script and 485 library scripts using 452652virt/85288res/12564shr/72180data kb, in 170usr/40sys/242real ms.
Pass 2: analyzed script: 1 probe, 2 functions, 0 embeds, 0 globals using 454236virt/86996res/12700shr/73764data kb, in 10usr/0sys/7real ms.
Pass 3: using cached <server>/.systemtap/cache/74/stap_7422abb93e345a17b57111389bdf1c69_1121.c
Pass 4: using cached <server>/.systemtap/cache/74/stap_7422abb93e345a17b57111389bdf1c69_1121.ko
Server: Module signed with MOK, fingerprint "3e:12:09:be:ab:7f:6c:de:89:fb:e9:9c:cd:92:84:a4:63:73:b2:a2"
Passes: via server  host=unknown address=127.0.0.1 port=32901 sysinfo="unknown" version=unknown certinfo="unknown" using 384836virt/17548res/15204shr/1740data kb, in 30usr/0sys/552real ms.
The kernel on your system requires modules to be signed for loading.
The module created by compiling your script must be signed by a systemtap compile-server.  [man stap-server]
--use-server was automatically selected in order to request compilation by a compile-server.
Pass 5: starting run.
ERROR: Cannot attach to module stap_7422abb93e345a17b57111389bdf1c69_1121 control channel; not running?
ERROR: Cannot attach to module stap_7422abb93e345a17b57111389bdf1c69_1121 control channel; not running?
ERROR: 'stap_7422abb93e345a17b57111389bdf1c69_1121' is not a zombie systemtap module.
WARNING: /usr/bin/staprun exited with status: 1
Pass 5: run completed in 10usr/10sys/33real ms.
Pass 5: run failed.  [man error::pass5]
[root@localhost ~]#
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