From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <jroedel@suse.de>
Subject: Re: [PATCH 3/3] virtio_pci: Use the DMA API
Date: Wed, 28 Oct 2015 11:25:24 +0900
Message-ID: <20151028022524.GE18467@suse.de>
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Cc: linux-kernel@vger.kernel.org,
	Christian Borntraeger <borntraeger@de.ibm.com>,
	Cornelia Huck <cornelia.huck@de.ibm.com>,
	Sebastian Ott <sebott@linux.vnet.ibm.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Christoph Hellwig <hch@lst.de>, benh@kernel.crashing.org,
	KVM <kvm@vger.kernel.org>, dwmw2@infradead.org,
	Martin Schwidefsky <schwidefsky@de.ibm.com>,
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	Andy Lutomirski <luto@amacapital.net>
To: Andy Lutomirski <luto@kernel.org>
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On Wed, Oct 28, 2015 at 11:15:30AM +0900, Joerg Roedel wrote:
> Same here, you need to call the dma_sync* functions when passing data
> from/to the virtio-device.

Okay, forget about this comment. This patch only converts to
dma_coherent allocations, which don't need synchronization.

> I think a good test for that is to boot a virtio kvm-guest with
> swiotlb=force and see if it still works.

But this holds, Its a good way to test if your changes work with
bounce-buffering. Together with DMA_API_DEBUG you also see if your
specified dma_directions are right.



	Joerg