Messages in this thread | | | Subject | Re: [PATCH v3 15/16] iommu: introduce page response function | From | Jean-Philippe Brucker <> | Date | Fri, 8 Dec 2017 13:51:48 +0000 |
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On 07/12/17 21:56, Alex Williamson wrote: [...] >> Seems like VFIO should enforce this quota, since the IOMMU layer doesn't >> know which device is assigned to which VM. If it's the IOMMU that enforces >> quotas per device and a VM has 15 devices assigned, then the guest can >> still DoS the IOMMU. > > VFIO also doesn't know about VMs. We know that devices attached to the > same container are probably used by the same user, but once we add > viommu, each device(group) uses its own container and we have no idea > they're associated. So, no to VM based accounting, and it seems like > an IOMMU problem, X number of outstanding requests per device. Thanks,
Ok. It's not clear anyway how the architecture and implementations expect us to virtualize stall, I'll try to clarify it.
Thanks, Jean
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