tree 4a6ac6aae66648bba9de57902ec98dfa5ae9b98d
parent 2225fd56049643c1a7d645c0ce9d499d43c7974e
author Alex Williamson <alex.williamson@redhat.com> 1334720804 -0600
committer Marcelo Tosatti <mtosatti@redhat.com> 1334804658 -0300

KVM: lock slots_lock around device assignment

As pointed out by Jason Baron, when assigning a device to a guest
we first set the iommu domain pointer, which enables mapping
and unmapping of memory slots to the iommu.  This leaves a window
where this path is enabled, but we haven't synchronized the iommu
mappings to the existing memory slots.  Thus a slot being removed
at that point could send us down unexpected code paths removing
non-existent pinnings and iommu mappings.  Take the slots_lock
around creating the iommu domain and initial mappings as well as
around iommu teardown to avoid this race.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>