kern/49008: rump (or atf) doesn't properly report KASSERT()

[bouyer%antioche.eu.org@localhost]

>Number:         49008
>Category:       kern
>Synopsis:       rump (or atf) doesn't properly report KASSERT()
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Jul 17 10:50:00 +0000 2014
>Originator:     Manuel Bouyer
>Release:        NetBSD 6.99.44
>Organization:
>Environment:
System: NetBSD test1 6.99.44 NetBSD 6.99.44 (XEN3PAE_DOMU) #4: Thu Jul 17 
11:59:48 CEST 2014  
bouyer@houla:/dsk/l1/misc/bouyer/tmp/i386/obj/dsk/l1/misc/bouyer/HEAD/src/sys/arch/i386/compile/XEN3PAE_DOMU
 i386
Architecture: i386
Machine: i386
>Description:
        I've been pointed out that some MPLS tests are failing since a commit
        of mine:
http://releng.netbsd.org/b5reports/i386/build/2014.05.13.20.29.59/test.html#net_mpls_t_mpls_fw_mplsfw4

        notice that stderr only has
Fail: incorrect exit status: 2, expected: 0
stdout:
PING 10.0.4.1 (10.0.4.1): 64 data bytes
  
----10.0.4.1 PING Statistics----
4 packets transmitted, 0 packets received, 100.0% packet loss 
  
stderr:
 
rump.halt: init failed: No such file or directory

        To debug this I setup 4 Xen guests to reproduce the setup of this
        test. Then the problem became immediatly obvious:
test2# panic: kernel diagnostic assertion "KERNEL_LOCKED_P()" failed: file 
"/dsk/l1/misc/bouyer/HEAD/src/sys/net/if_ethersubr.c", line 215

        I guess the second rump server of the test did panic and exit, but
        this message was not inclued in the test output.

>How-To-Repeat:
        revert if_mpls.c 1.16 and run atf in tests/net/mpls.
        Notice that the tests fails without usefull messages.
>Fix: