Bug#456804: rt2x00-source: Connection stops working after a while under load

[Tim Day]

On Sun, 2008-02-03 at 17:30 +0000, Ben Hutchings wrote:
> This is a known bug that should be fixed in later versions of the
> driver.  A fixed version of the driver is included in Linux 2.6.24.
> Please try installing that, if you can.  I am still working on an update
> to rt2x00-source for use in 2.6.22 and 2.6.23.

I've now tried running the Thinkpad with linux-image-2.6.24-1-686 from
sid for a few hours (rest of the system remains entirely lenny).

Well, it behaves differently under 2.6.24:

- Seems to be very slow compared with 2.6.22+rt2x00.  Under 2.6.24
iwconfig invariably says connected at 1Mbit (and this is confirmed by
iftop monitoring during file transfers).  Under 2.4.22 the same file
transfers (NFS) have no problem running at >6Mbit/s (iwconfig under
2.4.22 doesn't actually list rate, but that's what iftop shows).

- Instead of the connection hanging up under load (fixable by
reinserting the wifi card under 2.4.22) the entire machine crashes hard.
I haven't tried a serial-cable console to see if it's logging anything
useful.  It certainly seems to occur at the same sort of frequency as
the 2.4.22 hang, and is more likely under load.

- If I monitor the connection rate under 2.6.24
  while true; do sudo iwconfig wlan0 ; sleep 10 ; done
then quite often before a crash I get a couple of logs reporting
17Mbit/s connection speed and things speed up noticeably (I run various
X11 things over wifi).  Strange.

Note that I still have rt2x00-modules-2.6.22-3-686 2.0.12+git20071103-1
+2.6.22-6 installed (module-assistant built from rt2x00-source 2.0.12
+git20071103-3).  I haven't rebuilt these vs 2.6.24 so I assume it'll
ignore that module and use its own builtin support.
dpkg-query -S "rt2?00pci.ko"
yields
rt2x00-modules-2.6.22-3-686: /lib/modules/2.6.22-3-686/kernel/drivers/net/wireless/rt2x00pci.ko
rt2x00-modules-2.6.22-3-686: /lib/modules/2.6.22-3-686/kernel/drivers/net/wireless/rt2400pci.ko
rt2x00-modules-2.6.22-3-686: /lib/modules/2.6.22-3-686/kernel/drivers/net/wireless/rt2500pci.ko
linux-image-2.6.24-1-686: /lib/modules/2.6.24-1-686/kernel/drivers/net/wireless/rt2x00/rt2x00pci.ko
linux-image-2.6.24-1-686: /lib/modules/2.6.24-1-686/kernel/drivers/net/wireless/rt2x00/rt2400pci.ko
linux-image-2.6.24-1-686: /lib/modules/2.6.24-1-686/kernel/drivers/net/wireless/rt2x00/rt2500pci.ko
so I guess it must be loading the intended things.

I could get hold of the crash console log by serial cable if it'd be
helpful.  Any other suggestions ?  

FWIW, iwconfig wlan0 outputs (MAC, key, ESSID obfuscated) for 2.6.24:
wlan0     IEEE 802.11g  ESSID:"??????????"  
          Mode:Managed  Frequency:2.432 GHz  Access Point: ??:??:??:??:??:??   
          Bit Rate=1 Mb/s   Tx-Power=27 dBm   
          Retry min limit:7   RTS thr:off   Fragment thr=2346 B   
          Encryption key:????-????-????-????-????-????-????-????-????-????-????-????-????-????-????-???? [2]
          Link Quality=54/100  Signal level=-70 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0
and for 2.6.22:
wlan0     IEEE 802.11g  ESSID:"??????????"  
          Mode:Managed  Frequency:2.432 GHz  Access Point: ??:??:??:??:??:??
          Retry min limit:7   RTS thr:off   Fragment thr=2346 B   
          Encryption key:????-????-????-????-????-????-????-????-????-????-????-????-????-????-????-????
          Link Quality=46/100  Signal level=-57 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

Tim