kern/52587: NetBSD 8 panic after a few days of uptime

[dmb%yenn.ulegend.net@localhost]

>Number:         52587
>Category:       kern
>Synopsis:       NetBSD 8 panic after a few days of uptime
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Oct 01 10:25:01 +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: Fri Sep 15 12:57:31 UTC 2017 builds@yenn:/var/obj/sys/arch/amd64/compile/YENN amd64
Architecture: x86_64
Machine: amd64
>Description:
	After a few days of uptime the server paniced.

panic: kernel diagnostic assertion "(psref->psref_cpu == curcpu())" failed: file "/usr/src/sys/kern/subr_psref.c", line 296 passive reference transferred from CPU 1 to CPU 0
cpu0: Begin traceback...
vpanic() at netbsd:vpanic+0x140
ch_voltag_convert_in() at netbsd:ch_voltag_convert_in
psref_release() at netbsd:psref_release+0x1ee
bridge_input() at netbsd:bridge_input+0x8a3
tap_dev_write.isra.7() at netbsd:tap_dev_write.isra.7+0x12d
cdev_write() at netbsd:cdev_write+0x70
spec_write() at netbsd:spec_write+0xb2
VOP_WRITE() at netbsd:VOP_WRITE+0x37
vn_write() at netbsd:vn_write+0xec
dofilewrite() at netbsd:dofilewrite+0x97
sys_write() at netbsd:sys_write+0x5f
syscall() at netbsd:syscall+0x1d8
--- syscall (number 4) ---
71835583dfda:
cpu0: End traceback...

	There is OpenVPN/tap set up on the server, if this matters.  The CPU is AMD Athlon 64 X2.

>How-To-Repeat:
	Don't know...
>Fix:
	None known... Maybe disabling second core would be a workaround.

>Unformatted:
 		Sources from Sep 15, custom kernel, but only altq added, options GATEWAY, and
 		bridge_ipf set