kern/54387: DTrace Kernel module does not autoload on first use with GENERIC kernel

[venture37%geeklan.co.uk@localhost]

>Number:         54387
>Category:       kern
>Synopsis:       DTrace Kernel module does not autoload on first use with GENERIC kernel
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Jul 20 13:15:00 +0000 2019
>Originator:     Sevan Janiyan
>Release:        HEAD
>Organization:
>Environment:
NetBSD 8.99.51 (GENERIC) #0: Fri Jul 19 12:14:15 UTC 2019  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/i386/compile/GENERIC i386
>Description:
Attempting to run DTrace results in "WARNING: module error: incompatible module class for `dtrace' (3 != 1)"
Tested on NetBSD/i386 & amd64

One has to modload solaris & modload dtrace
From there, dtrace is able to load subsequent dtrace_* modules 

$ modstat |grep dtrace                                                     
dtrace              misc     filesys  -        2       - solaris
dtrace_sdt          misc     filesys  a        0       - dtrace
dtrace_syscall      misc     filesys  a        0       - dtrace
>How-To-Repeat:
Try running 'dtruss ls' or "dtrace -n 'BEGIN'"
Dtrace will not work until you have modload solaris; modload dtrace manually.
>Fix:
I suspect the change of the default value of WARNS for modules may be related but I'm not sure if the value should be reduced or this has highlighted a bug a in the module code.
Commit which changed the default WARNS value:
http://mail-index.netbsd.org/source-changes/2019/02/17/msg103560.html