Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...

[cascardo/linux.git] / drivers / vfio / Kconfig

diff --git a/drivers/vfio/Kconfig b/drivers/vfio/Kconfig
index 850d86c..da6e2ce 100644 (file)
--- a/drivers/vfio/Kconfig
+++ b/drivers/vfio/Kconfig
@@ -31,6 +31,21 @@ menuconfig VFIO
 
          If you don't know what to do here, say N.
 
+menuconfig VFIO_NOIOMMU
+       bool "VFIO No-IOMMU support"
+       depends on VFIO
+       help
+         VFIO is built on the ability to isolate devices using the IOMMU.
+         Only with an IOMMU can userspace access to DMA capable devices be
+         considered secure.  VFIO No-IOMMU mode enables IOMMU groups for
+         devices without IOMMU backing for the purpose of re-using the VFIO
+         infrastructure in a non-secure mode.  Use of this mode will result
+         in an unsupportable kernel and will therefore taint the kernel.
+         Device assignment to virtual machines is also not possible with
+         this mode since there is no IOMMU to provide DMA translation.
+
+         If you don't know what to do here, say N.
+
 source "drivers/vfio/pci/Kconfig"
 source "drivers/vfio/platform/Kconfig"
 source "virt/lib/Kconfig"