kern/38655: ld(4) on twa(4) and twe(4) panic at shutdown

[Simon Burge <simonb%NetBSD.org@localhost>]

>Number:         38655
>Category:       kern
>Synopsis:       ld(4) on twa(4) and twe(4) panic at shutdown
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed May 14 03:50:00 +0000 2008
>Originator:     Simon Burge
>Release:        NetBSD current as of May 13 2008
>Organization:
>Environment:
Architecture: all?
Machine: all?
>Description:
        pmf_system_shutdown() is called at splhigh() on all
        architectures (except atari!) and the twe(4) driver
        flush function ends up calling tsleep() and you get
        the following panic:

                panic: cpu_switcho: switching above IPL_SCHED

>How-To-Repeat:
        Reboot a system with a twa(4) or twe(4) (and possibly
        with or(4) and iop(4) but this isn't known).

>Fix:
        A suggested fix involving polling was posted in:
          http://mail-index.netbsd.org/tech-kern/2008/05/12/msg001353.html
        A reply for not doing this was posted in:
          http://mail-index.netbsd.org/tech-kern/2008/05/12/msg001354.html
        Further postings in:
          http://mail-index.netbsd.org/tech-kern/2008/05/12/msg001356.html
          http://mail-index.netbsd.org/tech-kern/2008/05/13/msg001360.html