Re: A question about state machine function state_next()

[Joerg Roedel <joro@8bytes.org>]

Hi Baoquan,

On Mon, Jun 01, 2015 at 05:09:02PM +0800, Baoquan He wrote:
> Then I am wondering  how amd_iommu_dma_ops is assigned. Maybe I need
> check all functions more clearly.

The AMD IOMMU driver only uses per-device dma_ops. They are assigned to
each device in device_dma_ops_init() at boot and in the
device_change_notifier() on hotplug events.


> Actually I am investigating how to port Zhenhua's kdump fix for intel
> iommu to amd iommu since the similar bug happened on systems with amd
> iommu. If you don't mind I can make these clean up during I understand
> these iommu codes. And if Zhenhua plan to post patch for amd fix, I
> can help review and test. Otherwise I can make some research and try
> to post a draft patch.

Thanks for looking into this. Unfortunatly this somehow conflicts with
my recent default-domain patch-set, which moves functionality into the
IOMMU core and converts the AMD driver to make use of it. I have no real
idea yet how to make both work, but it shouldn't be too hard. Maybe you can
have a look into that patch-set too?


	Joerg