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From: Lu Baolu <baolu.lu@linux.intel.com>
To: Joerg Roedel <joro@8bytes.org>, David Woodhouse <dwmw2@infradead.org>
Cc: ashok.raj@intel.com, jacob.jun.pan@intel.com,
	kevin.tian@intel.com, Zhenyu Wang <zhenyuw@linux.intel.com>,
	iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	Lu Baolu <baolu.lu@linux.intel.com>,
	Jacob Pan <jacob.jun.pan@linux.intel.com>
Subject: [PATCH 2/2] iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU
Date: Thu,  2 May 2019 09:34:26 +0800	[thread overview]
Message-ID: <20190502013426.16989-3-baolu.lu@linux.intel.com> (raw)
In-Reply-To: <20190502013426.16989-1-baolu.lu@linux.intel.com>

The kernel parameter igfx_off is used by users to disable
DMA remapping for the Intel integrated graphic device. It
was designed for bare metal cases where a dedicated IOMMU
is used for graphic. This doesn't apply to virtual IOMMU
case where an include-all IOMMU is used.  This makes the
kernel parameter work with virtual IOMMU as well.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Fixes: c0771df8d5297 ("intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
 drivers/iommu/intel-iommu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 00ad00193883..e078b13ce3d8 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3415,9 +3415,12 @@ static int __init init_dmars(void)
 		iommu_identity_mapping |= IDENTMAP_ALL;
 
 #ifdef CONFIG_INTEL_IOMMU_BROKEN_GFX_WA
-	iommu_identity_mapping |= IDENTMAP_GFX;
+	dmar_map_gfx = 0;
 #endif
 
+	if (!dmar_map_gfx)
+		iommu_identity_mapping |= IDENTMAP_GFX;
+
 	check_tylersburg_isoch();
 
 	if (iommu_identity_mapping) {
-- 
2.17.1

WARNING: multiple messages have this Message-ID (diff)
From: Lu Baolu <baolu.lu@linux.intel.com>
To: Joerg Roedel <joro@8bytes.org>, David Woodhouse <dwmw2@infradead.org>
Cc: kevin.tian@intel.com, ashok.raj@intel.com,
	linux-kernel@vger.kernel.org,
	Zhenyu Wang <zhenyuw@linux.intel.com>,
	iommu@lists.linux-foundation.org, jacob.jun.pan@intel.com
Subject: [PATCH 2/2] iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU
Date: Thu,  2 May 2019 09:34:26 +0800	[thread overview]
Message-ID: <20190502013426.16989-3-baolu.lu@linux.intel.com> (raw)
Message-ID: <20190502013426.VpB_-CAXdcI73AsVbtveJ0tYKwYbYt5S9-YEfJ8jSN0@z> (raw)
In-Reply-To: <20190502013426.16989-1-baolu.lu@linux.intel.com>

The kernel parameter igfx_off is used by users to disable
DMA remapping for the Intel integrated graphic device. It
was designed for bare metal cases where a dedicated IOMMU
is used for graphic. This doesn't apply to virtual IOMMU
case where an include-all IOMMU is used.  This makes the
kernel parameter work with virtual IOMMU as well.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Fixes: c0771df8d5297 ("intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Zhenyu Wang <zhenyuw@linux.intel.com>
---
 drivers/iommu/intel-iommu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 00ad00193883..e078b13ce3d8 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3415,9 +3415,12 @@ static int __init init_dmars(void)
 		iommu_identity_mapping |= IDENTMAP_ALL;
 
 #ifdef CONFIG_INTEL_IOMMU_BROKEN_GFX_WA
-	iommu_identity_mapping |= IDENTMAP_GFX;
+	dmar_map_gfx = 0;
 #endif
 
+	if (!dmar_map_gfx)
+		iommu_identity_mapping |= IDENTMAP_GFX;
+
 	check_tylersburg_isoch();
 
 	if (iommu_identity_mapping) {
-- 
2.17.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  parent reply	other threads:[~2019-05-02  1:34 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-02  1:34 [PATCH 0/2] iommu/vt-d: Small fixes for 5.2-rc1 Lu Baolu
2019-05-02  1:34 ` Lu Baolu
2019-05-02  1:34 ` [PATCH 1/2] iommu/vt-d: Set intel_iommu_gfx_mapped correctly Lu Baolu
2019-05-02  1:34   ` Lu Baolu
2019-05-02  1:34 ` Lu Baolu [this message]
2019-05-02  1:34   ` [PATCH 2/2] iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU Lu Baolu
2019-05-03 15:31 ` [PATCH 0/2] iommu/vt-d: Small fixes for 5.2-rc1 Joerg Roedel

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