[PATCH 1/2] iommu/vt-d: Set intel_iommu_gfx_mapped correctly

Lu Baolu
2019-05-02T01:41:38Z

The intel_iommu_gfx_mapped flag is exported by the Intel
IOMMU driver to indicate whether an IOMMU is used for the
graphic device. In a virtualized IOMMU environment (e.g.
QEMU), an include-all IOMMU is used for graphic device.
This flag is found to be clear even the IOMMU is used.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Reported-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Fixes: c0771df8d5297 ("intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.")
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/intel-iommu.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index e0c0febc6fa5..00ad00193883 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4068,9 +4068,7 @@ static void __init init_no_remapping_devices(void)

/* This IOMMU has *only* gfx devices. Either bypass it or
set the gfx_mapped flag, as appropriate */
- if (dmar_map_gfx) {
- intel_iommu_gfx_mapped = 1;
- } else {
+ if (!dmar_map_gfx) {
drhd->ignored = 1;
for_each_active_dev_scope(drhd->devices,
drhd->devices_cnt, i, dev)
@@ -4909,6 +4907,9 @@ int __init intel_iommu_init(void)
goto out_free_reserved_range;
}

+ if (dmar_map_gfx)
+ intel_iommu_gfx_mapped = 1;
+
init_no_remapping_devices();

ret = init_dmars();