Re: [Xen-devel] [PATCH v3 18/24] xen/passthrough: iommu_deassign_device_dt: By default reassign device to nobody

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 13.01.15 at 15:25, <julien.grall@xxxxxxxxxx> wrote:
> Currently, when the device is deassigned from a domain, we directly reassign
> to DOM0.
> 
> As the device may not have been correctly reset, this may lead to corruption 
> or
> expose some part of DOM0 memory. Also, we may have no way to reset some
> platform devices.
> 
> If Xen reassigns the device to "nobody", it may receive some global/context
> fault because the transaction has failed (indeed the context has been
> marked invalid). Unfortunately there is no simple way to quiesce a buggy
> hardware. I think we could live with that for a first version of platform
> device passthrough.
> 
> DOM0 will have to issue an hypercall to assign the device to itself if it
> wants to use it.
> 
> Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx>
> Cc: Jan Beulich <jbeulich@xxxxxxxx>

Looks like this is because of ...

>  xen/drivers/passthrough/device_tree.c | 9 +++------

... this. Which I think is a mistake, as I wasn't involved in the addition
of that file. I'd appreciate an update to ./MAINTAINERS adding this
file to the ARM section.

Jan


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