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Date: Sat, 09 Oct 2010 17:23:57 +0200
From: Felix Fietkau <nbd@openwrt.org>
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CC: "John W. Linville" <linville@tuxdriver.com>,
	"Luis R. Rodriguez" <lrodriguez@atheros.com>,
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Subject: Re: [ath9k-devel] [RFC] ath9k: Insert wmb before linking dma descriptors
References: <alpine.DEB.2.00.1010042059130.29449@vtdt3>	<20101005131744.GB4074@tuxdriver.com>	<20101005195039.GD11831@tux> <AANLkTikxayNdakE-MrCQWS10nZ3ZQk1pnEcHC+sMck1p@mail.gmail.com>
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On 2010-10-09 5:19 PM, Bj?rn Smedman wrote:
> On Tue, Oct 5, 2010 at 9:50 PM, Luis R. Rodriguez
> <lrodriguez@atheros.com> wrote:
>> Felix is more familiar with this area so I'll let him chime with
>> his ACK/NACK.
>>
>>  Luis
> 
> So Felix, what do you think? I realize it may not be a common problem
> on any currently popular platform, but don't you agree it is in
> principle unsafe to write to the ds_link field of dma descriptors
> without a guarantee that those writes will be performed in the
> intended order?
Haven't had time to review this in detail yet. I'll take another look at
it later...

- Felix