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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 17/17] iommu/vt-d: Remove BUG_ON in dmar_insert_dev_scope()
Date:   Thu, 13 Apr 2023 12:06:45 +0800
Message-Id: <20230413040645.46157-18-baolu.lu@linux.intel.com>
In-Reply-To: <20230413040645.46157-1-baolu.lu@linux.intel.com>
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From: Tina Zhang <tina.zhang@intel.com>

The dmar_insert_dev_scope() could fail if any unexpected condition is
encountered. However, in this situation, the kernel should attempt
recovery and proceed with execution. Remove BUG_ON with WARN_ON, so that
kernel can avoid being crashed when an unexpected condition occurs.

Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20230406065944.2773296-8-tina.zhang@intel.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/dmar.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 9346c6e7ebae..e35be3786bde 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -262,7 +262,8 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info,
 						   get_device(dev));
 				return 1;
 			}
-		BUG_ON(i >= devices_cnt);
+		if (WARN_ON(i >= devices_cnt))
+			return -EINVAL;
 	}
 
 	return 0;
-- 
2.34.1