Search Linux Wireless

Re: [ath9k-devel] ath9k: race conditions in dma

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Nov 1, 2010 at 4:43 PM, Ben Gamari <bgamari@xxxxxxxxx> wrote:
> On Mon, 1 Nov 2010 16:17:23 +0100, Björn Smedman <bjorn.smedman@xxxxxxxxxxx> wrote:
>> Hi all,
>>
>> I have an application that creates and destroys a lot of ap vifs and
>> does a lot of monitor frame injection. The recent ath9k rx locking
>> fixes have helped with stability in this use-case but there still
>> seems to be some tx/beacon related race condition(s). These manifests
>> themselves as follows on an AR913x based router running
>> compat-wireless-2010-10-19 (with locking fixes etc from openwrt):
>>
>> 1. TX DMA hangs under simultaneous high RX and TX load
>> 2. TX is completely hung but chip is never reset
>
> I have also observed both of these behaviors with just a standard
> hostapd single VIF configuration. Quite annoying. It seems to be better
> with recent wireless-testing trees.
>
> - Ben

I just posted "[RFC] ath9k: fix tx queue selection" with a patch that
fixes (or at least reduces) these two for me. I'm not sure it is the
whole story but at least in theory 1 could be caused by locking one tx
queue and actually transmitting on another. 2 is probably caused by
stopping one mac80211 queue and then starting another.

Ben, if you can easily trigger these problems on wireless-testing,
could you test with my patch and see if it helps? I'm especially
interested to see if it really fixes problem 1.

/Björn
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Host AP]     [ATH6KL]     [Linux Bluetooth]     [Linux Netdev]     [Kernel Newbies]     [Linux Kernel]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Samba]     [Device Mapper]
  Powered by Linux