[PATCH v2] PCI: Reset PCIe devices to stop ongoing DMA

[Bjorn Helgaas]

[+cc Rafael, linux-acpi]

On Tue, Jul 30, 2013 at 6:35 PM, Takao Indoh <indou.takao at jp.fujitsu.com> wrote:

> On x86, currently IOMMU initialization run *after* PCI enumeration, but
> what you are talking about is that it should be changed so that x86
> IOMMU initialization is done *before* PCI enumeration like sparc, right?

Yes.  I don't know whether or when that initialization order will ever
be changed, but I do think we should avoid building more
infrastructure that depends on the current order.

Changing the order is a pretty big deal because it's a lot more than
just the IOMMU.  Basically I think we should be enumerating ACPI
devices, including the IOMMU, before PCI devices, but there's a lot of
legacy involved in that area.  Added Rafael in case he has any
thoughts.

> Hmm, ok, I think I need to post attached patch to iommu list and
> discuss it including current order of x86 IOMMU initialization.