Message-ID: <4CCF4457.9040703@candelatech.com>
Date: Mon, 01 Nov 2010 15:51:03 -0700
From: Ben Greear <greearb@candelatech.com>
MIME-Version: 1.0
To: Peter Stuge <peter@stuge.se>
CC: =?UTF-8?B?QmrDtnJuIFNtZWRtYW4=?= <bjorn.smedman@venatech.se>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	"ath9k-devel@venema.h4ckr.net" <ath9k-devel@venema.h4ckr.net>,
	Bob Copeland <me@bobcopeland.com>,
	"John W. Linville" <linville@tuxdriver.com>
Subject: Re: [ath9k-devel] [RFC] ath9k: Insert wmb before linking	dma	descriptors
References: <20101005131744.GB4074@tuxdriver.com> <20101005195039.GD11831@tux>	<AANLkTikxayNdakE-MrCQWS10nZ3ZQk1pnEcHC+sMck1p@mail.gmail.com>	<4CB0890D.3050208@openwrt.org> <4CCA0908.6000105@candelatech.com>	<4CCA0B26.5010008@openwrt.org>	<AANLkTinu4_EcvzgS6AhxRYtSg=y=iwfcFtk0AhgOK-bS@mail.gmail.com>	<AANLkTi=+L+R1HowfmcLc7fTP+p0=u0T8bcYcob-TNyNb@mail.gmail.com>	<AANLkTinVu-DPdS43rMjDc0MMVDXMPHvKtbVfQJE8Ny=C@mail.gmail.com>	<AANLkTikqw5oVTd66DeQGrPgyPAqh66dm6jCvNFSeHpQi@mail.gmail.com> <20101101224533.5647.qmail@stuge.se>
In-Reply-To: <20101101224533.5647.qmail@stuge.se>
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Sender: linux-wireless-owner@vger.kernel.org

On 11/01/2010 03:45 PM, Peter Stuge wrote:
> Björn Smedman wrote:
>> long and unwanted weekend of debugging ath9k DMA errors
>
> Yeah, I've seen those as well, especially with AR5008 but also AR9002.
>
> I have severe intermittent issues with PCI functionality of an AR9280
> card. It locks up in a state where it either returns absolute garbage
> so severe that the kernel plain rejects it, or just mildly garbage
> data so that it reports corrupt PCI ids. It can fix itself in a
> running system, so that a later lspci shows the correct device ids
> and the driver actually loads and runs.
>
> I typically get PCI fatal interrupts after resurrecting the card
> (that takes a couple of power cycles including removing the laptop
> battery). I don't suppose anyone can explain *in detail* what causee
> these issues and what could be done to fix them?
>
> Finally I've also experienced complete system lockup after a
> previously working system was left on but idle overnight.
>
> All this fun with commit 2d10d8737ccdba752d60106abbc6ed4f37404923 but
> I believe these problems are nothing new.

I think at least some of that DEADBEAF stuff was related to the
DMA bugs.  Since we applied all of those patches, we haven't seen
those problems..but we also haven't been testing a whole lot lately..waiting
for wireless-testing to finish merging in those tx-dma patches before
we continue...

Thanks,
Ben

>
>
> //Peter
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> ath9k-devel@lists.ath9k.org
> https://lists.ath9k.org/mailman/listinfo/ath9k-devel


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com