From mboxrd@z Thu Jan  1 00:00:00 1970
From: Petko Manolov <petkan@nucleusys.com>
Subject: Re: [PATCH] net/usb: rtl8150: allocate URB transfer_buffer and
 setup_packet separately
Date: Thu, 8 Aug 2013 18:14:10 +0300 (EEST)
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Cc: netdev@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-usb@vger.kernel.org, "David S. Miller" <davem@davemloft.net>
To: Jussi Kivilinna <jussi.kivilinna@iki.fi>
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On Wed, 7 Aug 2013, Jussi Kivilinna wrote:

> rtl8150 allocates URB transfer_buffer and setup_packet as part of same 
> structure 'struct async_req'. This can cause same cacheline to be 
> DMA-mapped twice with same URB. This can lead to memory corruption on 
> some systems.

I can see performance impact due to the double mapping.  However, memory 
corruption seems a bit too much for sane cache and DMA controllers.  Out 
of interest - which is the architecture that will potentially corrupt the 
memory.


cheers,
Petko