kern/149786: bwn on Dell Inspiron 1150: connections stall

[Tom Uffner]

>Number:         149786
>Category:       kern
>Synopsis:       bwn on Dell Inspiron 1150: connections stall
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Aug 18 22:30:01 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Tom Uffner
>Release:        8-STABLE
>Organization:
>Environment:
FreeBSD zoe.uffner.com 8.1-STABLE FreeBSD 8.1-STABLE #4: Sun Aug  1 16:50:16 EDT 2010     tom at zoe.uffner.com:/usr/obj/usr/src/sys/ZOE  i386

>Description:
My laptop (Dell Inspiron 1150) has bwn supported wireless provided by a Broadcom internal mini-pci card. the identifying info printed os said card is

c2003 BROADCOM CORP
BCM94306MPSG REV4

pciconf -lv says:

siba_bwn0 at pci0:2:2:0:   class=0x028000 card=0x00031028 chip=0x432014e4 rev=0x03 hdr=0x00
    vendor     = 'Broadcom Corporation'
    device     = '802.11b/g Wireless LAN Controller (BCM4309)'
    class      = network

and dmesg says:

siba_bwn0: <Broadcom BCM4306 802.11b/g Wireless> mem 0xfcffc000-0xfcffdfff irq 11 at device 2.0 on pci2
bwn0 on siba_bwn0
bwn0: WLAN (chipid 0x4306 rev 5) PHY (analog 2 type 2 rev 2) RADIO (manuf 0x17f ver 0x2050 rev 2)
bwn0: DMA (30 bits)
bwn0: [FILTER]

this card seems to initialize properly and associate w/ any nearby access point. but when it is used to make TCP connections, the connection will always stall (and eventually time out and disconnect) any time it receives a substantial amount of data at once (the threshold seems to be a few hundred bytes). for example, i can ssh to another host, and as long as i stick to commands that only produce a few bytes of output it will work indefinitely. but as soon as i do anything that produces a more significant amount of output, for example "ls -al" or "man bwn" it will stall, and i get nothing more from that connection. http w/ firefox behaves similarly: small simple pages load, big ones lock up. the problem seems to affect individual connects rather then locking up the driver as a whole. when an ssh session locks up, i can open a new window and ssh to the same or any other host and the new session will also connect and behave as described above.

this occurs w/ GENERIC as well as my customized kernel (w/ all unused drivers, etc stripped from config). it does not affect other network drivers (such as builtin bfe port or an ath based wireless pccard).

none of the changes in current that have not yet been MFC'd had any effect, nor could i find any past revision where this problem did not occur.
>How-To-Repeat:
% ssh <some host>    // via bwn0 / wlan0 interface
% cd /usr/bin
% ls -al

session becomes non-responsive and will eventually time out & disconnect, it can be killed (-9) from another window or vty.
>Fix:
n/a

>Release-Note:
>Audit-Trail:
>Unformatted: