>-----Original Message-----
quoted text
>From: Johannes Berg [mailto:johannes@sipsolutions.net]
>Sent: Wednesday, February 11, 2009 11:50 PM
>To: Winkler, Tomas
>Cc: Yu, Fenghua; David Woodhouse; Ingo Molnar; Stephen Rothwell; Grumbach,
>Emmanuel; Zhu, Yi; Chris Wright; LKML; iommu@lists.linux-foundation.org
>Subject: RE: [PATCH]iwlan dma mapping read and write changes
>
>On Wed, 2009-02-11 at 22:47 +0100, Johannes Berg wrote:
>> > >> Indeed the firmware/ucode write back to host memory to update retry
>> > >> counter for APMDU packets. I'm not sure if this is needed for legacy
>> > >> traffic, though.
>> > >
>> > >I don't think they can be seeing AMPDU packets since that is, well,
>> > >broken?
>> >
>> > Currently I'm not aware of any other cases where memory is accessed
>> > back but I may have not complete info.  Will be back with the answer
>> > tomorrow.
>>
>> I don't think it really matters, since AMPDU packets will be fixed soon,
>> and for those you know it's necessary (and the report says that under
>> some other circumstances it's also necessary). Unless there'd be some
>> benefit from using BIDI only when we know it'll be needed, and using
>> TODEV in the other cases?
>
>Or if there's a firmware bug.

That's why it's better to clear the picture. 
Fenghua
What exact HW do you get this error?

Thanks
Tomas 

---------------------------------------------------------------------
Intel Israel (74) Limited

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.

--
unsubscribe notice
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/