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From: Lu Baolu <baolu.lu@linux.intel.com>
To: Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Kevin Tian <kevin.tian@intel.com>
Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org,
	Lu Baolu <baolu.lu@linux.intel.com>
Subject: [PATCH 1/1] iommu/vt-d: debugfs: Avoid dumping context command register
Date: Wed, 17 Sep 2025 10:50:51 +0800	[thread overview]
Message-ID: <20250917025051.143853-1-baolu.lu@linux.intel.com> (raw)

The register-based cache invalidation interface is in the process of being
replaced by the queued invalidation interface. The VT-d architecture
allows hardware implementations with a queued invalidation interface to
not implement the registers used for cache invalidation. Currently, the
debugfs interface dumps the Context Command Register unconditionally,
which is not reasonable.

Remove it to avoid potential access tonon-present registers.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/debugfs.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/iommu/intel/debugfs.c b/drivers/iommu/intel/debugfs.c
index 765edb3740e2..617fd81a80f0 100644
--- a/drivers/iommu/intel/debugfs.c
+++ b/drivers/iommu/intel/debugfs.c
@@ -62,7 +62,6 @@ static const struct iommu_regset iommu_regs_64[] = {
 	IOMMU_REGSET_ENTRY(CAP),
 	IOMMU_REGSET_ENTRY(ECAP),
 	IOMMU_REGSET_ENTRY(RTADDR),
-	IOMMU_REGSET_ENTRY(CCMD),
 	IOMMU_REGSET_ENTRY(PHMBASE),
 	IOMMU_REGSET_ENTRY(PHMLIMIT),
 	IOMMU_REGSET_ENTRY(IQH),
-- 
2.43.0


             reply	other threads:[~2025-09-17  2:52 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-09-17  2:50 Lu Baolu [this message]
2025-09-18  4:37 ` [PATCH 1/1] iommu/vt-d: debugfs: Avoid dumping context command register Baolu Lu

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