3 files changed, 15 insertions, 0 deletions

diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index fba4f6891680..270ed222a075 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -1316,3 +1316,13 @@ int dmar_reenable_qi(struct intel_iommu *iommu)
 
         return 0;
 }
+
+/*
+ * Check interrupt remapping support in DMAR table description.
+ */
+int dmar_ir_support(void)
+{
+        struct acpi_table_dmar *dmar;
+        dmar = (struct acpi_table_dmar *)dmar_tbl;
+        return dmar->flags & 0x1;
+}
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index ebfa47b79c5b..ac065144c01c 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -611,6 +611,9 @@ int __init intr_remapping_supported(void)
         if (disable_intremap)
                 return 0;
 
+        if (!dmar_ir_support())
+                return 0;
+
         for_each_drhd_unit(drhd) {
                 struct intel_iommu *iommu = drhd->iommu;
 
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 482dc91fd53a..4f0a72a9740c 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -360,4 +360,6 @@ extern void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 qdep,
 
 extern int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu);
 
+extern int dmar_ir_support(void);
+
 #endif