Re: blk_queue_bounce_limit() broken for mask=0xffffffff on 64bit archs

[Christoph Hellwig]

On Mon, Jan 09, 2017 at 11:48:11PM +0300, Nikita Yushchenko wrote:
> Hi
> 
> There is a use cases when architecture is 64-bit but hardware supports
> only DMA to lower 4G of address space. E.g. NVMe device on RCar PCIe host.

The solution is to shoot the SOC designer.  If that doesn't work use
swiotlb.