devfs in jail + logging out from console(ttyv1+) -> panic

[YONETANI Tomokazu]

On Sun, Oct 17, 2010 at 08:41:38AM +0900, YONETANI Tomokazu wrote:
> This is 100% reproducible(but only tried on x86_64).  If you're running
> a jail and using devfs inside the jail directory
> /etc/fstab:
>   devfs		/pbulk/1/dev	devfs	rw,jail	0	0
> 
> and login to console (other window than ttyv0), then logout from it,
> the kernel panics.  `uname -a' says:

A small addition: if I login from the console (ttyv0 this time) and
start pbulk program inside a GNU screen session,
  $ screen bulkbuild

detach it,
  (ctrl-A d)

reattach to it,
  $ screen -r

detach it again,
  (ctrl-A d)
then logout from the console and the kernel panics too.  If I log into
this machine via ssh and do the same thing, the kernel won't panic,
 so this may be specific to ttyvN.