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Date: Tue, 10 Apr 2018 20:10:20 +0200
From: Christoph Hellwig <hch@lst.de>
To: Robin Murphy <robin.murphy@arm.com>
Cc: Takashi Iwai <tiwai@suse.de>, Christoph Hellwig <hch@lst.de>,
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        Christian =?iso-8859-1?Q?K=F6nig?= <christian.koenig@amd.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Subject: Re: [PATCH] swiotlb: Fix unexpected swiotlb_alloc_coherent()
        failures
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On Tue, Apr 10, 2018 at 06:50:04PM +0100, Robin Murphy wrote:
> In the first one, the machine appears to have enough RAM that most of it is 
> beyond the device's 36-bit DMA mask, thus it's fairly likely for the 
> initial direct alloc to come back with something unsuitable.

But we should try a GFP_DMA32 allocation first, so this is a bit
surprising.