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Date:   Mon, 6 Dec 2021 06:36:27 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Lu Baolu <baolu.lu@linux.intel.com>
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Subject: Re: [PATCH v3 04/18] driver core: platform: Add driver dma ownership
 management
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I really hate the amount of boilerplate code that having this in each
bus type causes.

Between that and the suggestion from Joerg I wonder if we could do the
following again:

 - add new no_kernel_dma flag to struct device_driver
 - set this flag for the various vfio drivers
 - skip claiming the kernel dma ownership for those (or rather release
   it if the suggestion from Joerg works out)