Skip to contentSkip to conversation

Prevent devices with RMRRs from being placed into SI Domain

PATCH Superseded Tom Mingarelli 2 participants 3 messages Oct 17, 2012 – Oct 21, 2012 IOMMU

v3 of 4 Superseded Latest is v4 →

lore
Share & tools
lore
#0 lore raw

PATCH v3 1/1 Prevent devices with RMRRs from being placed into SI Domain

This patch is to prevent devices that have RMRRs associated with them to not be placed into the SI Domain during init. We don't put USB devices into this category, however. This fixes the issue where the RMRR info for devices being placed in and out of the SI Domain gets lost.

----
PATCH v1: https://lkml.org/lkml/2012/6/15/204
PATCH v2: https://lkml.org/lkml/2012/9/18/354

drivers/iommu/intel-iommu.c | 30 ++++++++++++++++++++++++++++++

 1 files changed, 30 insertions(+), 0 deletions(-)
drivers/iommu/intel-iommu.c renamed from drivers/iommu/intel-iommu.c.ORIG +30 -0
diff -up ./drivers/iommu/intel-iommu.c.ORIG ./drivers/iommu/intel-iommu.c
@@ -2320,8 +2320,38 @@ static int domain_add_dev_info(struct dm
 	return 0;
 }
 
+static bool device_has_rmrr(struct pci_dev *dev)
+{
+	struct dmar_rmrr_unit *rmrr;
+	int i;
+
+	for_each_rmrr_units(rmrr) {
+		for (i = 0; i < rmrr->devices_cnt; i++) {
+			/*
+			 * Here we are just concerned with checking each device
+			 * that has an RMRR associated with it and not allow it
+			 * to be placed into the SI Domain during startup.
+			*/
+			if (rmrr->devices[i] == dev)
+				return true;
+		}
+	}
+	return false;
+}
+
 static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
 {
+
+	/*
+	 * This is where we will refuse any device that has an
+	 * RMRR associated with it and is not a USB device and
+	 * NOT allow it to be placed into the SI Domain. We don't
+	 * need a separate bit for this because it could be ANY device.
+	 */
+	if (device_has_rmrr(pdev) &&
+		(pdev->class >> 8) != PCI_CLASS_SERIAL_USB)
+			return 0;
+
 	if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
 		return 1;
 
author Tested-by Shuah Khan on v3 1/1
#1 lore raw

I meant to edit the preamble with no reference to init. This patch will prevent any device with an RMRR association from getting placed into the SI Domain and any time.

Tom

-----Original Message-----
From: Mingarelli, Thomas
Sent: Wednesday, October 17, 2012 4:17 PM
To: Alex Williamson; David Woodhouse; Don Dutile
Cc: Khan, Shuah; Mingarelli, Thomas; Knippers, Linda; iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org; [email protected]
Subject: [PATCH v3] Prevent devices with RMRRs from being placed into SI Domain

This patch is to prevent devices that have RMRRs associated with them to not be placed into the SI Domain during init. We don't put USB devices into this category, however. This fixes the issue where the RMRR info for devices being placed in and out of the SI Domain gets lost.

----
PATCH v1: https://lkml.org/lkml/2012/6/15/204
PATCH v2: https://lkml.org/lkml/2012/9/18/354

drivers/iommu/intel-iommu.c | 30 ++++++++++++++++++++++++++++++

 1 files changed, 30 insertions(+), 0 deletions(-)
drivers/iommu/intel-iommu.c renamed from drivers/iommu/intel-iommu.c.ORIG +30 -0
diff -up ./drivers/iommu/intel-iommu.c.ORIG ./drivers/iommu/intel-iommu.c
@@ -2320,8 +2320,38 @@ static int domain_add_dev_info(struct dm
 	return 0;
 }
 
+static bool device_has_rmrr(struct pci_dev *dev)
+{
+	struct dmar_rmrr_unit *rmrr;
+	int i;
+
+	for_each_rmrr_units(rmrr) {
+		for (i = 0; i < rmrr->devices_cnt; i++) {
+			/*
+			 * Here we are just concerned with checking each device
+			 * that has an RMRR associated with it and not allow it
+			 * to be placed into the SI Domain during startup.
+			*/
+			if (rmrr->devices[i] == dev)
+				return true;
+		}
+	}
+	return false;
+}
+
 static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
 {
+
+	/*
+	 * This is where we will refuse any device that has an
+	 * RMRR associated with it and is not a USB device and
+	 * NOT allow it to be placed into the SI Domain. We don't
+	 * need a separate bit for this because it could be ANY device.
+	 */
+	if (device_has_rmrr(pdev) &&
+		(pdev->class >> 8) != PCI_CLASS_SERIAL_USB)
+			return 0;
+
 	if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
 		return 1;
 
#2 lore raw
In reply to Tom Mingarelli
Quoted 57 lines · Tom Mingarelli

This patch is to prevent devices that have RMRRs associated with them to not be placed into the SI Domain during init. We don't put USB devices into this category, however. This fixes the issue where the RMRR info for devices being placed in and out of the SI Domain gets lost.

----
PATCH v1: https://lkml.org/lkml/2012/6/15/204
PATCH v2: https://lkml.org/lkml/2012/9/18/354

drivers/iommu/intel-iommu.c | 30 ++++++++++++++++++++++++++++++

  1 files changed, 30 insertions(+), 0 deletions(-)

diff -up ./drivers/iommu/intel-iommu.c.ORIG ./drivers/iommu/intel-iommu.c

drivers/iommu/intel-iommu.c renamed from drivers/iommu/intel-iommu.c.ORIG +30 -0
@@ -2320,8 +2320,38 @@ static int domain_add_dev_info(struct dm
  	return 0;
  }
 
+static bool device_has_rmrr(struct pci_dev *dev)
+{
+	struct dmar_rmrr_unit *rmrr;
+	int i;
+
+	for_each_rmrr_units(rmrr) {
+		for (i = 0; i < rmrr->devices_cnt; i++) {
+			/*
+			 * Here we are just concerned with checking each device
+			 * that has an RMRR associated with it and not allow it
+			 * to be placed into the SI Domain during startup.
+			*/
+			if (rmrr->devices[i] == dev)
+				return true;
+		}
+	}
+	return false;
+}
+
  static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
  {
+
+	/*
+	 * This is where we will refuse any device that has an
+	 * RMRR associated with it and is not a USB device and
+	 * NOT allow it to be placed into the SI Domain. We don't
+	 * need a separate bit for this because it could be ANY device.
+	 */
+	if (device_has_rmrr(pdev) &&
+		(pdev->class >> 8) != PCI_CLASS_SERIAL_USB)
+			return 0;
+
  	if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
  		return 1;
 
Quoted 6 lines

_______________________________________________
iommu mailing list iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
.

I applied this patch to my system and booted with IOMMU pass through mode enabled. Without the patch my system would panic or wedge. I also applied a be2net patch I'm working on and was able to get successful netperf runs with IOMMU pass through mode enabled.

-Craig