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Date: Tue, 07 Feb 2012 09:25:42 +0100
From: Johannes Berg <johannes@sipsolutions.net>
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To: Stanislaw Gruszka <sgruszka@redhat.com>
CC: Wey-Yi Guy <wey-yi.w.guy@intel.com>,
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Subject: Re: [RFC 3/4] iwlwifi: cleanup/fix memory barriers
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On 2/7/2012 9:11 AM, Stanislaw Gruszka wrote:
>> Technically, PCIe bridges can reorder writes as well, so we really
>> need to do a dummy read somewhere -- we were discussing this
>> internally recently as well.
>
> PCIe can reorder writes only if they come from different CPUs,
> good examples are in "LOCKS VS I/O ACCESSES" in
> Documentation/memory-barriers.txt

Good point, I was confusing this and write posting. Don't think we have 
an issue with write posting here so we should be OK.

johannes