kern/163237: AR5416 as HostAP. Delays among clients when

[Gustau Pérez]

>Number:         163237
>Category:       kern
>Synopsis:       AR5416 as HostAP. Delays among clients when
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Dec 13 08:40:13 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator:     Gustau Pérez
>Release:        FreeBSD 10.0-CURRENT #31 r227346
>Organization:
>Environment:
FreeBSD harkserver 9.9-CURRENT FreeBSD 10.0-CURRENT #31 r227364: Thu Nov 24 18:04:08 CET 2011     root at harkserver:/usr/obj/root/deviant2/sys/CUSTOM  amd64

>Description:
  This is the environment:

  I'm using an AR5416 card acting as an AP with hostap in 11g mode. I'm running g mode because I did not have time to test the 11n work yet. The box is running CURRENT/AMD64.

  These are the symptoms:

  A few days ago I began to see very big delays between the AP and my laptop (which has an AR9287 with FreeBSD/AMD64 CURRENT). I tried a simple icmp with 1 second between pings. It is quite curious thing that the delays increase from 30ms until around 100ms (those times are in the same order of magnitude of a ping to google) and then they fall til 30ms again. It did not work like that.

   I tested with different clients (an iPhone, a laptop running FreeBSD with an Intel 3945, an asus eeePC laptop with windows7 and other devices). All of them showed the same behavior. No matter if I'm accessing the HostAP box or trying to access internet, everything takes long. 

   The bisect lead me to commit r227364, which is one quite large. Running the previous commit fixes it. 
>How-To-Repeat:
Compile a custom kernel with r227364 in a box with an AR5416 and use the box as an AP. 
>Fix:


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