iommu/vt-d: Enable Translation only if it was previously disabled

Do not touch the TE bit unless we know translation is
disabled.

Tested-by: ZhenHua Li <zhen-hual@hp.com>
Tested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index e40c858..a98a7b2 100644 (file)
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3204,7 +3204,9 @@ domains_done:
                if (ret)
                        goto free_iommu;
 
-               iommu_enable_translation(iommu);
+               if (!translation_pre_enabled(iommu))
+                       iommu_enable_translation(iommu);
+
                iommu_disable_protect_mem_regions(iommu);
        }