kern/48044: panic: kernel diagnostic assertion "uvmexp.swpgonly + npages <= uvmexp.swpginuse" failed

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         48044
>Category:       kern
>Synopsis:       panic: kernel diagnostic assertion "uvmexp.swpgonly + npages 
><= uvmexp.swpginuse" failed
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Jul 10 16:05:00 +0000 2013
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current source date 2013.07.08.08.21.12
>Organization:
>Environment:
System: NetBSD
Architecture: amd64
Machine: amd64
>Description:

Saw this in 
http://releng.netbsd.org/b5reports/amd64/build/2013.07.08.08.21.12/test.log :

  lib/libtre/t_exhaust (320/569): 1 test cases
      regcomp_too_big: panic: kernel diagnostic assertion "uvmexp.swpgonly + 
npages <= uvmexp.swpginuse" failed: file 
"/tmp/bracket/build/2013.07.08.08.21.12-amd64/src/sys/uvm/uvm_pager.c", line 471
  cpu0: Begin traceback...
  vpanic() at netbsd:vpanic+0x136
  kern_assert() at netbsd:kern_assert+0x48
  uvm_aio_aiodone_pages() at netbsd:uvm_aio_aiodone_pages+0x538
  uvm_aio_aiodone() at netbsd:uvm_aio_aiodone+0xa6
  workqueue_worker() at netbsd:workqueue_worker+0x7f
  cpu0: End traceback...

>How-To-Repeat:

A second occurrence is at
http://releng.netbsd.org/b5reports/amd64/build/2013.07.08.05.36.23/test.log

Apart from that, I don't know.

>Fix: