port-amd64/43842: KASSERT when running tests under compat_netbsd32

[njoly%pasteur.fr@localhost]

>Number:         43842
>Category:       port-amd64
>Synopsis:       KASSERT when running tests under compat_netbsd32
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-amd64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Sep 06 12:40:00 +0000 2010
>Originator:     Nicolas Joly
>Release:        NetBSD 5.99.39
>Organization:
Institut Pasteur
>Environment:
System: NetBSD lanfeust.sis.pasteur.fr 5.99.39 NetBSD 5.99.39 (LANFEUST) #15: 
Mon Sep 6 11:41:09 CEST 2010 
njoly%lanfeust.sis.pasteur.fr@localhost:/local/src/NetBSD/obj.amd64/sys/arch/amd64/compile/LANFEUST
 amd64
Architecture: x86_64
Machine: amd64
>Description:
Running NetBSD tests in a i386 chroot generate a KASSERT.

njoly@lanfeust [~]> chroot -u njoly -g users /misc/chroot/netbsd32 ksh
njoly@lanfeust [netbsd32:njoly]> cd /usr/tests
njoly@lanfeust [netbsd32:tests]> atf-run | atf-report                          
[...]
fs/msdosfs/t_snapshot (74/244): 1 test cases
    snapshot: Passed.

fs/nfs/t_mountd (75/244): 1 test cases
    mountdhup: 
[...PANIC...]

panic: kernel diagnostic assertion "error == 0" failed: file "/local/src/NetBSD/
src/sys/arch/amd64/amd64/netbsd32_machdep.c", line 943
fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip ffffffff8022b28d cs 8 rflags 246 cr2  fbc9e790 cpl 0 rsp
ffff80004a81fb40
Stopped in pid 5562.20 (t_mountd) at    netbsd:breakpoint+0x5:  leave
db{0}> bt
breakpoint() at netbsd:breakpoint+0x5
panic() at netbsd:panic+0x2ba
kern_assert() at netbsd:kern_assert+0x2d
startlwp32() at netbsd:startlwp32+0x92

While this one is consistently triggered with atf-run, there is no problem
when the test program is launched directly.

njoly@lanfeust [~]> export LD_LIBRARY_PATH=/misc/chroot/netbsd32/usr/lib
njoly@lanfeust [~]> /misc/chroot/netbsd32/usr/tests/fs/nfs/t_mountd mountdhup
rumpnfsd: Cannot get information for `udp6'
rumpnfsd: Cannot get information for `tcp6'
rpcbind debugging enabled.
[...]
doing opt -maproot=0:0
Adding a default entry
Got line 
expected_failure: PR kern/5844: op failed with EACCES

>How-To-Repeat:
Run tests in a netbsd i386 chroot.
>Fix: