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authorFenghua Yu <fenghua.yu@intel.com>2009-04-24 17:30:20 -0700
committerDavid Woodhouse <David.Woodhouse@intel.com>2009-04-29 06:54:34 +0100
commit4ed0d3e6c64cfd9ba4ceb2099b10d1cf8ece4320 (patch)
tree950bacfaf57040aafbcc2ea9b52eb171d35c23bd /Documentation
parent091069740304c979f957ceacec39c461d0192158 (diff)
downloadop-kernel-dev-4ed0d3e6c64cfd9ba4ceb2099b10d1cf8ece4320.zip
op-kernel-dev-4ed0d3e6c64cfd9ba4ceb2099b10d1cf8ece4320.tar.gz
Intel IOMMU Pass Through Support
The patch adds kernel parameter intel_iommu=pt to set up pass through mode in context mapping entry. This disables DMAR in linux kernel; but KVM still runs on VT-d and interrupt remapping still works. In this mode, kernel uses swiotlb for DMA API functions but other VT-d functionalities are enabled for KVM. KVM always uses multi level translation page table in VT-d. By default, pass though mode is disabled in kernel. This is useful when people don't want to enable VT-d DMAR in kernel but still want to use KVM and interrupt remapping for reasons like DMAR performance concern or debug purpose. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Acked-by: Weidong Han <weidong@intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/kernel-parameters.txt1
1 files changed, 1 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 600cdd7..fa4faeb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -965,6 +965,7 @@ and is between 256 and 4096 characters. It is defined in the file
nomerge
forcesac
soft
+ pt [x86, IA64]
io7= [HW] IO7 for Marvel based alpha systems
See comment before marvel_specify_io7 in
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