diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index d93c4bd7de75..52311a6d9d3f 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3498,7 +3498,13 @@ static int __init init_dmars(void)
 
 #ifdef CONFIG_INTEL_IOMMU_SVM
 		if (pasid_supported(iommu) && ecap_prs(iommu->ecap)) {
+			/*
+			 * Call dmar_alloc_hwirq() with dmar_global_lock held,
+			 * could cause possible lock race condition.
+			 */
+			up_write(&dmar_global_lock);
 			ret = intel_svm_enable_prq(iommu);
+			down_write(&dmar_global_lock);
 			if (ret)
 				goto free_iommu;
 		}