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Re: "Consolidate get_dma_ops" breaks Xen on ARM

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On 04/10/17 17:31, Stefano Stabellini wrote:
> I think the reason is that, as you can see, if (dev && dev->dma_ops),
> dev->dma_ops is returned, while before this changes, xen_dma_ops was
> returned on Xen on ARM.
>
> Unfortunately DMA cannot work properly without using the appropriate
> xen_dma_ops. See drivers/xen/swiotlb-xen.c and arch/arm/xen/mm.c for
> more details. (The problem is easy to spot, but I wasn't CC'ed on the
> patch.)
>
> I don't know how to solve this problem without introducing some sort of
> if (xen()) in include/linux/dma-mapping.h.

Sorry but I don't have access to an ARM development system. Does your 
comment apply to dev == NULL only, dev != NULL only or perhaps to both? 
If your comment applies to dev != NULL only, can you check whether 
adding something like set_dma_ops(dev, get_arch_dma_ops(NULL)) to the 
appropriate ARM arch_setup_dma_ops() function is sufficient?

Thanks,

Bart.

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Thread

"Consolidate get_dma_ops" breaks Xen on ARM Stefano Stabellini <sstabellini@kernel.org> - 2017-04-11 02:40 +0200
  Re: "Consolidate get_dma_ops" breaks Xen on ARM Bart Van Assche <Bart.VanAssche@sandisk.com> - 2017-04-11 03:20 +0200
    Re: "Consolidate get_dma_ops" breaks Xen on ARM Julien Grall <julien.grall@arm.com> - 2017-04-11 14:50 +0200
      Re: "Consolidate get_dma_ops" breaks Xen on ARM Catalin Marinas <catalin.marinas@arm.com> - 2017-04-11 15:40 +0200
        Re: "Consolidate get_dma_ops" breaks Xen on ARM Stefano Stabellini <sstabellini@kernel.org> - 2017-04-12 01:40 +0200
          Re: "Consolidate get_dma_ops" breaks Xen on ARM Catalin Marinas <catalin.marinas@arm.com> - 2017-04-12 10:40 +0200
          Re: "Consolidate get_dma_ops" breaks Xen on ARM Julien Grall <julien.grall@arm.com> - 2017-04-13 16:10 +0200
            Re: "Consolidate get_dma_ops" breaks Xen on ARM Stefano Stabellini <sstabellini@kernel.org> - 2017-04-13 20:10 +0200

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