kern/44296: iwn(4) panics during suspend

[Jukka Ruohonen <jruohonen%iki.fi@localhost>]

>Number:         44296
>Category:       kern
>Synopsis:       iwn(4) panics during suspend
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 30 09:25:00 +0000 2010
>Originator:     Jukka Ruohonen
>Release:        5.99.42
>Organization:
-
>Environment:
amd64
>Description:

The iwn(4) driver makes a 5.99.42 amd64 system panic upon suspend;

        ...
        audio0: device_pmf_unlock.2350, sysctl dvl_nlock 0 dvl_nwait 0
        dv_flags 87 iwn0iwn0: device_pmf_lock1.2323, sysctl dvl_nlock 1
        dvl_nwait 0 dv_flags 7
        uvm_faulg(0xffff80004c353b80, 0x0, 4) -> e
        fatal page fault in supervisor mode
        trap type 6 code 10 rip 0 cs 8 rflacs 10246 cr2 0 cpl 6
        rsp ffff80004dc66938
        kernel: page fault trap, code=0
        Stopped in pid 3.1 (sysctl) at 0: invalid address
        db{1}>

Suspend is entirely reliable if iwn(4) is disabled via userconf(4).
This is a regression. The machine suspends and resumes fine in 5.1.

>How-To-Repeat:

Try to suspend a 4.99.42 system.

>Fix:

Under investigation.