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From: Yanfei Xu <yanfei.xu@intel.com>
To: dwmw2@infradead.org, baolu.lu@linux.intel.com, joro@8bytes.org,
	will@kernel.org, robin.murphy@arm.com
Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, yanfei.xu@intel.com
Subject: [PATCH 2/2] iommu/vt-d: Use BUG_ON to check NULL value of 'table'
Date: Tue, 30 May 2023 17:25:03 +0800	[thread overview]
Message-ID: <20230530092503.152926-3-yanfei.xu@intel.com> (raw)
In-Reply-To: <20230530092503.152926-1-yanfei.xu@intel.com>

Checking NULL value of 'table' variable deserves a BUG_ON as the
following code will trigger a crash by dereferencing the NULL
'table' pointer. Crash in advance with BUG_ON to avoid WARN_ON
plus NULL pointer dereferencing can simplify the crash log.

Signed-off-by: Yanfei Xu <yanfei.xu@intel.com>
---
 drivers/iommu/intel/iommu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index e98f1b122b49..8aa3bfdb7f95 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1944,7 +1944,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 	if (sm_supported(iommu)) {
 		unsigned long pds;
 
-		WARN_ON(!table);
+		BUG_ON(!table);
 
 		/* Setup the PASID DIR pointer: */
 		pds = context_get_sm_pds(table);
-- 
2.34.1


  parent reply	other threads:[~2023-05-30  9:27 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-30  9:25 [PATCH 0/2] Misc cleanup for iommu/vt-d Yanfei Xu
2023-05-30  9:25 ` [PATCH 1/2] iommu/vt-d: Remove the dead code in init_iommu_hw() Yanfei Xu
2023-05-31  3:24   ` Baolu Lu
2023-05-31  6:55     ` Yanfei Xu
2023-06-01  1:15       ` Baolu Lu
2023-06-01  7:49         ` Yanfei Xu
2023-05-30  9:25 ` Yanfei Xu [this message]
2023-05-31  3:26   ` [PATCH 2/2] iommu/vt-d: Use BUG_ON to check NULL value of 'table' Baolu Lu
2023-05-31  7:09     ` Yanfei Xu
2023-06-01  1:23       ` Baolu Lu
2023-06-01  4:47         ` Yanfei Xu
2023-06-02 14:32     ` Jason Gunthorpe

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