The core VFIO infrastructure more or less allows VFIO devices to work
on any normal guest PCI host bridge (PHB) without extra logic.
However, the "spapr-pci-host-bridge" device (as opposed to the special
"spapr-pci-vfio-host-bridge" device) breaks this by using a partially
KVM accelerated implementation of the guest kernel IOMMU which won't
work with VFIO devices, without additional kernel support.
This patch allows VFIO devices to work on the spapr-pci-host-bridge,
by having it switch off KVM TCE acceleration when a VFIO device is
added to the PHB (either on startup, or by hotplug).
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
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