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Date: Fri, 3 Aug 2018 00:06:38 -0700
From: Christoph Hellwig <hch@infradead.org>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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Subject: Re: [RFC 0/4] Virtio uses DMA API for all devices
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On Thu, Aug 02, 2018 at 11:53:08PM +0300, Michael S. Tsirkin wrote:
> > We don't need cache flushing tricks.
> 
> You don't but do real devices on same platform need them?

IBMs power plaforms are always cache coherent.  There are some powerpc
platforms have not cache coherent DMA, but I guess this scheme isn't
intended for them.