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From:   Lu Baolu <baolu.lu@linux.intel.com>
To:     Joerg Roedel <joro@8bytes.org>
Cc:     Tina Zhang <tina.zhang@intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        iommu@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: [PATCH v2 14/17] iommu/vt-d: Remove BUG_ON when domain->pgd is NULL
Date:   Thu, 13 Apr 2023 12:06:42 +0800
Message-Id: <20230413040645.46157-15-baolu.lu@linux.intel.com>
In-Reply-To: <20230413040645.46157-1-baolu.lu@linux.intel.com>
References: <20230413040645.46157-1-baolu.lu@linux.intel.com>
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From: Tina Zhang <tina.zhang@intel.com>

When performing domain_context_mapping or getting dma_pte of a pfn, the
availability of the domain page table directory is ensured. Therefore,
the domain->pgd checkings are unnecessary.

Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20230406065944.2773296-5-tina.zhang@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/iommu.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index dd61bb554aa7..f11347a590d7 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -915,8 +915,6 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,
 	int level = agaw_to_level(domain->agaw);
 	int offset;
 
-	BUG_ON(!domain->pgd);
-
 	if (!domain_pfn_supported(domain, pfn))
 		/* Address beyond IOMMU's addressing capabilities. */
 		return NULL;
@@ -1910,8 +1908,6 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 	pr_debug("Set context mapping for %02x:%02x.%d\n",
 		bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
 
-	BUG_ON(!domain->pgd);
-
 	spin_lock(&iommu->lock);
 	ret = -ENOMEM;
 	context = iommu_context_addr(iommu, bus, devfn, 1);
-- 
2.34.1