iommu/vt-d: Use bounce buffer for untrusted devices

The Intel VT-d hardware uses paging for DMA remapping.
The minimum mapped window is a page size. The device
drivers may map buffers not filling the whole IOMMU
window. This allows the device to access to possibly
unrelated memory and a malicious device could exploit
this to perform DMA attacks. To address this, the
Intel IOMMU driver will use bounce pages for those
buffers which don't fill whole IOMMU pages.

Cc: Ashok Raj <[email protected]>
Cc: Jacob Pan <[email protected]>
Cc: Kevin Tian <[email protected]>
Signed-off-by: Lu Baolu <[email protected]>
Tested-by: Xu Pengfei <[email protected]>
Tested-by: Mika Westerberg <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>

0 files changed, 0 insertions, 0 deletions