Re: wlan0: Rx: len(24576) > MAX(2304) ? "Take2"

From: Jouni Malinen (
Date: 2002-07-17 11:15:08 UTC

On Wed, Jul 17, 2002 at 04:31:34PM +1000, dennis wrote:

> You may have seen my earlier post re the syslog entry for...
> "Jul 17 16:12:42 wifi kernel: wlan0: Rx: len(24576) > MAX(2304)"
> I'm still seeing it appear for my wireless interface, anyone know what it means ?

This log entry comes when the driver receives a frame with invalid length value for some reason (and drops the frame). I would guess that most common reason for this is some sort of concurrency problem with BAP0 and BAP1 access (i.e., TX and RX frames) and the driver gets packet descriptor data from incorrect position. I have been seeing this mostly on when using monitor mode, but apparently it still occurs also with normal data frames. This 24576 bytes is 0x6000 in hex and it would thus like a bitfield or something like that..

I think I will have to take some time and experiment with some locking changes. I have seen some cases that do not seem to match the documented behavior (at least I have assumed that both BAP0 and BAP1 could be used concurrently). One possibility would be to allow only one BAP transfer at a time which should remove these problems, but it would probably also add some extra load on the host side.

Jouni Malinen                                            PGP id EFC895FA

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