kern/52596: [netbsd-8] Another NetBSD 8 panic

[Dominik%yenn.ulegend.net@localhost,Bialy%yenn.ulegend.net@localhost]

>Number:         52596
>Category:       kern
>Synopsis:       Another netbsd-8 panic
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Oct 06 05:40:00 +0000 2017
>Originator:     Dominik Bialy
>Release:        NetBSD 8.0_BETA
>Organization:
Underlegend Networks
>Environment:
System: NetBSD yenn 8.0_BETA NetBSD 8.0_BETA (YENN) #0: Tue Oct 3 11:10:20 UTC 2017 builds@yenn:/var/obj/sys/arch/amd64/compile/YENN amd64
Architecture: x86_64
Machine: amd64
>Description:
	This bug is hunting us since the upgrade to netbsd-8, lately it became
	more frequent.  From the dmesg:
fatal privileged instruction fault in supervisor mode
trap type 0 code 0 rip 0xffffffff80224b52 cs 0x8 rflags 0x10013 cr2 0xffff800047d69000 ilevel 0x8 rsp 0xfffffe80405a3e98
curlwp 0xfffffe812f860340 pid 440.2 lowest kstack 0xfffffe80405a02c0
panic: trap
cpu1: Begin traceback...
vpanic() at netbsd:vpanic+0x140
snprintf() at netbsd:snprintf
trap() at netbsd:trap+0xc6b
--- trap (number 0) ---
xsave() at netbsd:xsave+0xa
fpudna() at netbsd:fpudna+0x61
cpu1: End traceback...

	The CPU is Athlon 64 X2.
	I can provide any futher info needed.
>How-To-Repeat:
	I don't know.
>Fix:
	I don't know.