[PATCH 0/3] iommu: Add PCI vendor:device ID to IOMMU fault logs

[PATCH 0/3] iommu: Add PCI vendor:device ID to IOMMU fault logs

[Yigit Oguz]

IOMMU fault and event logs currently identify devices using only their
PCI segment/bus/device/function (SSSS:BB:DD.F). While mapping a single
BDF to a device type is straightforward, doing so at scale across many
hosts and thousands of fault events requires additional tooling and
manual cross-referencing. Including the vendor:device ID directly in
the log line makes each event self-contained and immediately actionable
without any post-processing.

This series adds vendor:device ID (VVVV:DDDD) to IOMMU event logs for
ARM SMMUv3, Intel VT-d and AMD IOMMU.

Before:
  arm-smmu-v3 arm-smmu-v3.0.auto: event: F_TRANSLATION client: 0000:2b:11.6
    sid: 0x158e ssid: 0x0 iova: 0x280000000000 ipa: 0x0
  DMAR: [DMA Write NO_PASID] Request device [86:00.0] fault addr 0xe0000000
    [fault reason 0x05] PTE Write access is not set
  AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 domain=0x000a
    address=0xe0000000 flags=0x0020]

After:
  arm-smmu-v3 arm-smmu-v3.0.auto: event: F_TRANSLATION client: 0000:2b:11.6 [8086:1533]
    sid: 0x158e ssid: 0x0 iova: 0x280000000000 ipa: 0x0
  DMAR: [DMA Write NO_PASID] Request device [0000:86:00.0 8086:1533] fault addr 0xe0000000
    [fault reason 0x05] PTE Write access is not set
  AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 8086:1533 domain=0x000a
    address=0xe0000000 flags=0x0020]

Patch 1 adds vendor:device ID to ARM SMMUv3 translation fault logs.
Patch 2 adds PCI segment and vendor:device ID to Intel VT-d DMAR
        fault logs.
Patch 3 adds a devid_str helper and vendor:device ID to all AMD IOMMU
        event log paths.

Testing:
Build-tested against mainline Linux (torvalds/master).

Runtime-tested on a custom downstream branch on ARM SMMUv3, Intel VT-d and
AMD IOMMU hosts. Translation faults were induced in a virtualized setup
by removing DMA mappings for an in-use region, causing the assigned device's
subsequent DMA transactions to hit unmapped IOVAs and produce
translation fault events. The resulting log lines were verified to
contain the PCI vendor:device ID on all three platforms.

Lilit Janpoladyan (1):
  iommu/arm-smmu-v3: Print PCI vendor:device ID in SMMU translation
    fault logs

Yigit Oguz (2):
  iommu/vt-d: Add PCI segment and vendor:device ID to DMAR fault logs
  iommu/amd: Add vendor:device ID to AMD IOMMU event logs

 drivers/iommu/amd/iommu.c                   | 94 +++++++++++++--------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 ++++++-
 drivers/iommu/intel/dmar.c                  | 33 +++++---
 3 files changed, 104 insertions(+), 52 deletions(-)

-- 
2.47.3




Amazon Web Services Development Center Germany GmbH
Tamara-Danz-Str. 13
10243 Berlin
Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597

[PATCH 1/3] iommu/arm-smmu-v3: Print PCI vendor:device ID in SMMU translation fault logs

[Yigit Oguz]

From: Lilit Janpoladyan <lilitj@amazon.com>

For translation, address-size, access, and permission faults, look up
the pci_dev from the event and append the PCI vendor:device ID after
the device name, e.g.:

  event: F_TRANSLATION client: 0001:02:02.4 [1d0f:8061] sid: ...

For non-PCI devices or unassigned SIDs the output is unchanged.

Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 ++++++++++++++++++---
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index e8d7dbe495f0..ab1afa36965a 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2213,12 +2213,30 @@ static void arm_smmu_dump_raw_event(struct arm_smmu_device *smmu, u64 *raw,
 
 #define ARM_SMMU_EVT_KNOWN(e)	((e)->id < ARRAY_SIZE(event_str) && event_str[(e)->id])
 #define ARM_SMMU_LOG_EVT_STR(e) ARM_SMMU_EVT_KNOWN(e) ? event_str[(e)->id] : "UNKNOWN"
-#define ARM_SMMU_LOG_CLIENT(e)	(e)->dev ? dev_name((e)->dev) : "(unassigned sid)"
+
+/* "SSSS:BB:DD.F [VVVV:DDDD]\0" — 12 + 1 + 11 + 1 = 25; round to power of 2 */
+#define ARM_SMMU_CLIENT_LEN	32
+
+static const char *arm_smmu_fmt_client(struct arm_smmu_event *e, char *buf, size_t sz)
+{
+	struct pci_dev *p;
+
+	if (!e->dev)
+		return "(unassigned sid)";
+	if (!dev_is_pci(e->dev))
+		return dev_name(e->dev);
+
+	p = to_pci_dev(e->dev);
+	snprintf(buf, sz, "%s [%04x:%04x]", dev_name(e->dev), p->vendor, p->device);
+	return buf;
+}
 
 static void arm_smmu_dump_event(struct arm_smmu_device *smmu, u64 *raw,
 				struct arm_smmu_event *evt,
 				struct ratelimit_state *rs)
 {
+	char clientbuf[ARM_SMMU_CLIENT_LEN];
+
 	if (!__ratelimit(rs))
 		return;
 
@@ -2230,7 +2248,8 @@ static void arm_smmu_dump_event(struct arm_smmu_device *smmu, u64 *raw,
 	case EVT_ID_ACCESS_FAULT:
 	case EVT_ID_PERMISSION_FAULT:
 		dev_err(smmu->dev, "event: %s client: %s sid: %#x ssid: %#x iova: %#llx ipa: %#llx",
-			ARM_SMMU_LOG_EVT_STR(evt), ARM_SMMU_LOG_CLIENT(evt),
+			ARM_SMMU_LOG_EVT_STR(evt),
+			arm_smmu_fmt_client(evt, clientbuf, ARM_SMMU_CLIENT_LEN),
 			evt->sid, evt->ssid, evt->iova, evt->ipa);
 
 		dev_err(smmu->dev, "%s %s %s %s \"%s\"%s%s stag: %#x",
@@ -2247,14 +2266,16 @@ static void arm_smmu_dump_event(struct arm_smmu_device *smmu, u64 *raw,
 	case EVT_ID_CD_FETCH_FAULT:
 	case EVT_ID_VMS_FETCH_FAULT:
 		dev_err(smmu->dev, "event: %s client: %s sid: %#x ssid: %#x fetch_addr: %#llx",
-			ARM_SMMU_LOG_EVT_STR(evt), ARM_SMMU_LOG_CLIENT(evt),
+			ARM_SMMU_LOG_EVT_STR(evt),
+			arm_smmu_fmt_client(evt, clientbuf, ARM_SMMU_CLIENT_LEN),
 			evt->sid, evt->ssid, evt->fetch_addr);
 
 		break;
 
 	default:
 		dev_err(smmu->dev, "event: %s client: %s sid: %#x ssid: %#x",
-			ARM_SMMU_LOG_EVT_STR(evt), ARM_SMMU_LOG_CLIENT(evt),
+			ARM_SMMU_LOG_EVT_STR(evt),
+			arm_smmu_fmt_client(evt, clientbuf, ARM_SMMU_CLIENT_LEN),
 			evt->sid, evt->ssid);
 	}
 }
-- 
2.47.3




Amazon Web Services Development Center Germany GmbH
Tamara-Danz-Str. 13
10243 Berlin
Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597

[PATCH 2/3] iommu/vt-d: Add PCI segment and vendor:device ID to DMAR fault logs

[Yigit Oguz]

Include the full SSSS:BB:DD.F address with PCI segment and
vendor:device ID (VVVV:DDDD) in DMAR fault messages. Uses
iommu->segment for the PCI domain and pci_get_domain_bus_and_slot
to look up the pci_dev. Falls back to segment:BDF without
vendor:device if the device is not found.

This brings Intel IOMMU fault logging in line with the ARM SMMUv3
event decoding, making it easier to identify faulting devices
(e.g. after FLR) without cross-referencing lspci.

Before:
  DMAR: [DMA Write NO_PASID] Request device [86:00.0] fault addr 0xe0000000
	[fault reason 0x05] PTE Write access is not set

After:
  DMAR: [DMA Write NO_PASID] Request device [0000:86:00.0 8086:1533] fault addr 0xe0000000
  	[fault reason 0x05] PTE Write access is not set

Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
Assisted-by: Claude:claude-4.6-opus
---
 drivers/iommu/intel/dmar.c | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index d33c119a935e..225fa498d714 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -1890,30 +1890,39 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
 {
 	const char *reason;
 	int fault_type;
+	u8 bus = source_id >> 8;
+	u8 devfn = source_id & 0xFF;
+	struct pci_dev *pdev;
+	char devid[48];
 
 	reason = dmar_get_fault_reason(fault_reason, &fault_type);
 
+	pdev = pci_get_domain_bus_and_slot(iommu->segment, bus, devfn);
+	if (pdev) {
+		snprintf(devid, sizeof(devid), "%04x:%02x:%02x.%d %04x:%04x",
+			 iommu->segment, bus, PCI_SLOT(devfn), PCI_FUNC(devfn),
+			 pdev->vendor, pdev->device);
+		pci_dev_put(pdev);
+	} else {
+		snprintf(devid, sizeof(devid), "%04x:%02x:%02x.%d",
+			 iommu->segment, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
+	}
+
 	if (fault_type == INTR_REMAP) {
-		pr_err("[INTR-REMAP] Request device [%02x:%02x.%d] fault index 0x%llx [fault reason 0x%02x] %s\n",
-		       source_id >> 8, PCI_SLOT(source_id & 0xFF),
-		       PCI_FUNC(source_id & 0xFF), addr >> 48,
-		       fault_reason, reason);
+		pr_err("[INTR-REMAP] Request device [%s] fault index 0x%llx [fault reason 0x%02x] %s\n",
+		       devid, addr >> 48, fault_reason, reason);
 
 		return 0;
 	}
 
 	if (pasid == IOMMU_PASID_INVALID)
-		pr_err("[%s NO_PASID] Request device [%02x:%02x.%d] fault addr 0x%llx [fault reason 0x%02x] %s\n",
+		pr_err("[%s NO_PASID] Request device [%s] fault addr 0x%llx [fault reason 0x%02x] %s\n",
 		       type ? "DMA Read" : "DMA Write",
-		       source_id >> 8, PCI_SLOT(source_id & 0xFF),
-		       PCI_FUNC(source_id & 0xFF), addr,
-		       fault_reason, reason);
+		       devid, addr, fault_reason, reason);
 	else
-		pr_err("[%s PASID 0x%x] Request device [%02x:%02x.%d] fault addr 0x%llx [fault reason 0x%02x] %s\n",
+		pr_err("[%s PASID 0x%x] Request device [%s] fault addr 0x%llx [fault reason 0x%02x] %s\n",
 		       type ? "DMA Read" : "DMA Write", pasid,
-		       source_id >> 8, PCI_SLOT(source_id & 0xFF),
-		       PCI_FUNC(source_id & 0xFF), addr,
-		       fault_reason, reason);
+		       devid, addr, fault_reason, reason);
 
 	dmar_fault_dump_ptes(iommu, source_id, addr, pasid);
 
-- 
2.47.3




Amazon Web Services Development Center Germany GmbH
Tamara-Danz-Str. 13
10243 Berlin
Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597

[PATCH 3/3] iommu/amd: Add vendor:device ID to AMD IOMMU event logs

[Yigit Oguz]

Add amd_iommu_devid_str() helper that formats PCI device identity as
SSSS:BB:DD.F VVVV:DDDD by looking up the pci_dev via
pci_get_domain_bus_and_slot. Falls back to SSSS:BB:DD.F when the
device is not found.

Before:
  AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 domain=0x000a
  	address=0xe0000000 flags=0x0020]

After:
  AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 8086:1533 domain=0x000a
  	address=0xe0000000 flags=0x0020]

Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
Assisted-by: Claude:claude-4.6-opus
---
 drivers/iommu/amd/iommu.c | 94 ++++++++++++++++++++++++---------------
 1 file changed, 58 insertions(+), 36 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 01171361f9bc..441b4a7e85d5 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -779,11 +779,34 @@ static void dump_command(unsigned long phys_addr)
 		pr_err("CMD[%d]: %08x\n", i, cmd->data[i]);
 }
 
+#define AMD_IOMMU_DEVID_SIZE	48
+
+static void amd_iommu_devid_str(struct amd_iommu *iommu, u16 devid, char *buf,
+				size_t size)
+{
+	struct pci_dev *pdev;
+
+	pdev = pci_get_domain_bus_and_slot(iommu->pci_seg->id,
+					   PCI_BUS_NUM(devid), devid & 0xff);
+	if (pdev) {
+		snprintf(buf, size, "%04x:%02x:%02x.%x %04x:%04x",
+			 iommu->pci_seg->id, PCI_BUS_NUM(devid),
+			 PCI_SLOT(devid), PCI_FUNC(devid),
+			 pdev->vendor, pdev->device);
+		pci_dev_put(pdev);
+	} else {
+		snprintf(buf, size, "%04x:%02x:%02x.%x",
+			 iommu->pci_seg->id, PCI_BUS_NUM(devid),
+			 PCI_SLOT(devid), PCI_FUNC(devid));
+	}
+}
+
 static void amd_iommu_report_rmp_hw_error(struct amd_iommu *iommu, volatile u32 *event)
 {
 	struct iommu_dev_data *dev_data = NULL;
 	int devid, vmg_tag, flags;
 	struct pci_dev *pdev;
+	char devid_str[AMD_IOMMU_DEVID_SIZE];
 	u64 spa;
 
 	devid   = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
@@ -796,15 +819,16 @@ static void amd_iommu_report_rmp_hw_error(struct amd_iommu *iommu, volatile u32
 	if (pdev)
 		dev_data = dev_iommu_priv_get(&pdev->dev);
 
+	amd_iommu_devid_str(iommu, devid, devid_str, sizeof(devid_str));
+
 	if (dev_data) {
 		if (__ratelimit(&dev_data->rs)) {
-			pci_err(pdev, "Event logged [RMP_HW_ERROR vmg_tag=0x%04x, spa=0x%llx, flags=0x%04x]\n",
-				vmg_tag, spa, flags);
+			pci_err(pdev, "Event logged [RMP_HW_ERROR device=%s vmg_tag=0x%04x, spa=0x%llx, flags=0x%04x]\n",
+				devid_str, vmg_tag, spa, flags);
 		}
 	} else {
-		pr_err_ratelimited("Event logged [RMP_HW_ERROR device=%04x:%02x:%02x.%x, vmg_tag=0x%04x, spa=0x%llx, flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			vmg_tag, spa, flags);
+		pr_err_ratelimited("Event logged [RMP_HW_ERROR device=%s vmg_tag=0x%04x, spa=0x%llx, flags=0x%04x]\n",
+			devid_str, vmg_tag, spa, flags);
 	}
 
 	if (pdev)
@@ -816,6 +840,7 @@ static void amd_iommu_report_rmp_fault(struct amd_iommu *iommu, volatile u32 *ev
 	struct iommu_dev_data *dev_data = NULL;
 	int devid, flags_rmp, vmg_tag, flags;
 	struct pci_dev *pdev;
+	char devid_str[AMD_IOMMU_DEVID_SIZE];
 	u64 gpa;
 
 	devid     = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
@@ -831,13 +856,12 @@ static void amd_iommu_report_rmp_fault(struct amd_iommu *iommu, volatile u32 *ev
 
 	if (dev_data) {
 		if (__ratelimit(&dev_data->rs)) {
-			pci_err(pdev, "Event logged [RMP_PAGE_FAULT vmg_tag=0x%04x, gpa=0x%llx, flags_rmp=0x%04x, flags=0x%04x]\n",
-				vmg_tag, gpa, flags_rmp, flags);
+			pci_err(pdev, "Event logged [RMP_PAGE_FAULT device=%s vmg_tag=0x%04x, gpa=0x%llx, flags_rmp=0x%04x, flags=0x%04x]\n",
+				devid_str, vmg_tag, gpa, flags_rmp, flags);
 		}
 	} else {
-		pr_err_ratelimited("Event logged [RMP_PAGE_FAULT device=%04x:%02x:%02x.%x, vmg_tag=0x%04x, gpa=0x%llx, flags_rmp=0x%04x, flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			vmg_tag, gpa, flags_rmp, flags);
+		pr_err_ratelimited("Event logged [RMP_PAGE_FAULT device=%s vmg_tag=0x%04x, gpa=0x%llx, flags_rmp=0x%04x, flags=0x%04x]\n",
+			devid_str, vmg_tag, gpa, flags_rmp, flags);
 	}
 
 	if (pdev)
@@ -856,12 +880,15 @@ static void amd_iommu_report_page_fault(struct amd_iommu *iommu,
 {
 	struct iommu_dev_data *dev_data = NULL;
 	struct pci_dev *pdev;
+	char devid_str[AMD_IOMMU_DEVID_SIZE];
 
 	pdev = pci_get_domain_bus_and_slot(iommu->pci_seg->id, PCI_BUS_NUM(devid),
 					   devid & 0xff);
 	if (pdev)
 		dev_data = dev_iommu_priv_get(&pdev->dev);
 
+	amd_iommu_devid_str(iommu, devid, devid_str, sizeof(devid_str));
+
 	if (dev_data) {
 		/*
 		 * If this is a DMA fault (for which the I(nterrupt)
@@ -872,9 +899,8 @@ static void amd_iommu_report_page_fault(struct amd_iommu *iommu,
 			/* Device not attached to domain properly */
 			if (dev_data->domain == NULL) {
 				pr_err_ratelimited("Event logged [Device not attached to domain properly]\n");
-				pr_err_ratelimited("  device=%04x:%02x:%02x.%x domain=0x%04x\n",
-						   iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid),
-						   PCI_FUNC(devid), domain_id);
+				pr_err_ratelimited("  device=%s domain=0x%04x\n",
+						   devid_str, domain_id);
 				goto out;
 			}
 
@@ -887,13 +913,12 @@ static void amd_iommu_report_page_fault(struct amd_iommu *iommu,
 		}
 
 		if (__ratelimit(&dev_data->rs)) {
-			pci_err(pdev, "Event logged [IO_PAGE_FAULT domain=0x%04x address=0x%llx flags=0x%04x]\n",
-				domain_id, address, flags);
+			pci_err(pdev, "Event logged [IO_PAGE_FAULT device=%s domain=0x%04x address=0x%llx flags=0x%04x]\n",
+				devid_str, domain_id, address, flags);
 		}
 	} else {
-		pr_err_ratelimited("Event logged [IO_PAGE_FAULT device=%04x:%02x:%02x.%x domain=0x%04x address=0x%llx flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			domain_id, address, flags);
+		pr_err_ratelimited("Event logged [IO_PAGE_FAULT device=%s domain=0x%04x address=0x%llx flags=0x%04x]\n",
+			devid_str, domain_id, address, flags);
 	}
 
 out:
@@ -909,6 +934,7 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
 	int count = 0;
 	u64 address, ctrl;
 	u32 pasid;
+	char devid_str[AMD_IOMMU_DEVID_SIZE];
 
 retry:
 	type    = (event[1] >> EVENT_TYPE_SHIFT)  & EVENT_TYPE_MASK;
@@ -934,24 +960,22 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
 		return;
 	}
 
+	amd_iommu_devid_str(iommu, devid, devid_str, sizeof(devid_str));
+
 	switch (type) {
 	case EVENT_TYPE_ILL_DEV:
-		dev_err(dev, "Event logged [ILLEGAL_DEV_TABLE_ENTRY device=%04x:%02x:%02x.%x pasid=0x%05x address=0x%llx flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			pasid, address, flags);
+		dev_err(dev, "Event logged [ILLEGAL_DEV_TABLE_ENTRY device=%s pasid=0x%05x address=0x%llx flags=0x%04x]\n",
+			devid_str, pasid, address, flags);
 		dev_err(dev, "Control Reg : 0x%llx\n", ctrl);
 		dump_dte_entry(iommu, devid);
 		break;
 	case EVENT_TYPE_DEV_TAB_ERR:
-		dev_err(dev, "Event logged [DEV_TAB_HARDWARE_ERROR device=%04x:%02x:%02x.%x "
-			"address=0x%llx flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			address, flags);
+		dev_err(dev, "Event logged [DEV_TAB_HARDWARE_ERROR device=%s address=0x%llx flags=0x%04x]\n",
+			devid_str, address, flags);
 		break;
 	case EVENT_TYPE_PAGE_TAB_ERR:
-		dev_err(dev, "Event logged [PAGE_TAB_HARDWARE_ERROR device=%04x:%02x:%02x.%x pasid=0x%04x address=0x%llx flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			pasid, address, flags);
+		dev_err(dev, "Event logged [PAGE_TAB_HARDWARE_ERROR device=%s pasid=0x%04x address=0x%llx flags=0x%04x]\n",
+			devid_str, pasid, address, flags);
 		break;
 	case EVENT_TYPE_ILL_CMD:
 		dev_err(dev, "Event logged [ILLEGAL_COMMAND_ERROR address=0x%llx]\n", address);
@@ -962,14 +986,12 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
 			address, flags);
 		break;
 	case EVENT_TYPE_IOTLB_INV_TO:
-		dev_err(dev, "Event logged [IOTLB_INV_TIMEOUT device=%04x:%02x:%02x.%x address=0x%llx]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			address);
+		dev_err(dev, "Event logged [IOTLB_INV_TIMEOUT device=%s address=0x%llx]\n",
+			devid_str, address);
 		break;
 	case EVENT_TYPE_INV_DEV_REQ:
-		dev_err(dev, "Event logged [INVALID_DEVICE_REQUEST device=%04x:%02x:%02x.%x pasid=0x%05x address=0x%llx flags=0x%04x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
-			pasid, address, flags);
+		dev_err(dev, "Event logged [INVALID_DEVICE_REQUEST device=%s pasid=0x%05x address=0x%llx flags=0x%04x]\n",
+			devid_str, pasid, address, flags);
 		break;
 	case EVENT_TYPE_RMP_FAULT:
 		amd_iommu_report_rmp_fault(iommu, event);
@@ -980,8 +1002,8 @@ static void iommu_print_event(struct amd_iommu *iommu, void *__evt)
 	case EVENT_TYPE_INV_PPR_REQ:
 		pasid = PPR_PASID(*((u64 *)__evt));
 		tag = event[1] & 0x03FF;
-		dev_err(dev, "Event logged [INVALID_PPR_REQUEST device=%04x:%02x:%02x.%x pasid=0x%05x address=0x%llx flags=0x%04x tag=0x%03x]\n",
-			iommu->pci_seg->id, PCI_BUS_NUM(devid), PCI_SLOT(devid), PCI_FUNC(devid),
+		dev_err(dev, "Event logged [INVALID_PPR_REQUEST device=%s pasid=0x%05x address=0x%llx flags=0x%04x tag=0x%03x]\n",
+			devid_str,
 			pasid, address, flags, tag);
 		break;
 	default:
-- 
2.47.3




Amazon Web Services Development Center Germany GmbH
Tamara-Danz-Str. 13
10243 Berlin
Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger
Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B
Sitz: Berlin
Ust-ID: DE 365 538 597

Re: [PATCH 1/3] iommu/arm-smmu-v3: Print PCI vendor:device ID in SMMU translation fault logs

[Pranjal Shrivastava]

On Wed, May 06, 2026 at 03:05:37PM +0000, Yigit Oguz wrote:
> From: Lilit Janpoladyan <lilitj@amazon.com>
> 
> For translation, address-size, access, and permission faults, look up
> the pci_dev from the event and append the PCI vendor:device ID after
> the device name, e.g.:
> 
>   event: F_TRANSLATION client: 0001:02:02.4 [1d0f:8061] sid: ...
> 
> For non-PCI devices or unassigned SIDs the output is unchanged.
> 
> Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
> Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 ++++++++++++++++++---
>  1 file changed, 25 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index e8d7dbe495f0..ab1afa36965a 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -2213,12 +2213,30 @@ static void arm_smmu_dump_raw_event(struct arm_smmu_device *smmu, u64 *raw,
>  
>  #define ARM_SMMU_EVT_KNOWN(e)	((e)->id < ARRAY_SIZE(event_str) && event_str[(e)->id])
>  #define ARM_SMMU_LOG_EVT_STR(e) ARM_SMMU_EVT_KNOWN(e) ? event_str[(e)->id] : "UNKNOWN"
> -#define ARM_SMMU_LOG_CLIENT(e)	(e)->dev ? dev_name((e)->dev) : "(unassigned sid)"
> +
> +/* "SSSS:BB:DD.F [VVVV:DDDD]\0" — 12 + 1 + 11 + 1 = 25; round to power of 2 */
> +#define ARM_SMMU_CLIENT_LEN	32
> +

Nit: s/ARM_SMMU_CLIENT_LEN/ARM_SMMU_LOG_CLIENT_LEN to maintain the
convention?

> +static const char *arm_smmu_fmt_client(struct arm_smmu_event *e, char *buf, size_t sz)
> +{
> +	struct pci_dev *p;

Minor nit: maybe we could intialized it here?

struct pci_dev *p = to_pci_dev(e->dev);

Not a strong opinion though.

> +
> +	if (!e->dev)
> +		return "(unassigned sid)";
> +	if (!dev_is_pci(e->dev))
> +		return dev_name(e->dev);
> +
> +	p = to_pci_dev(e->dev);
> +	snprintf(buf, sz, "%s [%04x:%04x]", dev_name(e->dev), p->vendor, p->device);
> +	return buf;
> +}
>  
>  static void arm_smmu_dump_event(struct arm_smmu_device *smmu, u64 *raw,
>  				struct arm_smmu_event *evt,
>  				struct ratelimit_state *rs)
>  {
> +	char clientbuf[ARM_SMMU_CLIENT_LEN];

Nit: s/clientbuf/client_str ?

I was able to test this with 7.1-rc1 & it looks good:

   [  106.880820] arm-smmu-v3 9050000.smmuv3: event: F_TRANSLATION client: 0000:00:01.0 [8086:10c9] sid: 0x8 ssid: 0x0 iova: 0xffffc000 ipa: 0x0
   [  106.880855] arm-smmu-v3 9050000.smmuv3: unpriv data read s1 "Input address caused fault" stag: 0x0
   [  106.880894] arm-smmu-v3 9050000.smmuv3: event 0x10 received:
   [  106.880922] arm-smmu-v3 9050000.smmuv3:     0x0000000800000010
   [  106.880948] arm-smmu-v3 9050000.smmuv3:     0x0000020800000000
   [  106.880974] arm-smmu-v3 9050000.smmuv3:     0x00000000ffffc004
   [  106.881001] arm-smmu-v3 9050000.smmuv3:     0x0000000000000000
   [  106.881030] arm-smmu-v3 9050000.smmuv3: event: F_TRANSLATION client: 0000:00:01.0 [8086:10c9] sid: 0x8 ssid: 0x0 iova: 0xffffc004 ipa: 0x0
   [  106.881061] arm-smmu-v3 9050000.smmuv3: unpriv data read s1 "Input address caused fault" stag: 0x0
   [  106.881104] arm-smmu-v3 9050000.smmuv3: event 0x10 received:
   [  106.881136] arm-smmu-v3 9050000.smmuv3:     0x0000000800000010
   [  106.881163] arm-smmu-v3 9050000.smmuv3:     0x0000020800000000
   [  106.881189] arm-smmu-v3 9050000.smmuv3:     0x00000000ffffc008
   [  106.881215] arm-smmu-v3 9050000.smmuv3:     0x0000000000000000

Apart from the nits above:

Reviewed-by: Pranjal Shrivastava <praan@google.com>
Tested-by: Pranjal Shrivastava <praan@google.com>

Thanks,
Praan

Re: [PATCH 2/3] iommu/vt-d: Add PCI segment and vendor:device ID to DMAR fault logs

[Pranjal Shrivastava]

On Wed, May 06, 2026 at 03:05:38PM +0000, Yigit Oguz wrote:
> Include the full SSSS:BB:DD.F address with PCI segment and
> vendor:device ID (VVVV:DDDD) in DMAR fault messages. Uses
> iommu->segment for the PCI domain and pci_get_domain_bus_and_slot
> to look up the pci_dev. Falls back to segment:BDF without
> vendor:device if the device is not found.
> 
> This brings Intel IOMMU fault logging in line with the ARM SMMUv3
> event decoding, making it easier to identify faulting devices
> (e.g. after FLR) without cross-referencing lspci.
> 
> Before:
>   DMAR: [DMA Write NO_PASID] Request device [86:00.0] fault addr 0xe0000000
> 	[fault reason 0x05] PTE Write access is not set
> 
> After:
>   DMAR: [DMA Write NO_PASID] Request device [0000:86:00.0 8086:1533] fault addr 0xe0000000
>   	[fault reason 0x05] PTE Write access is not set
> 
> Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
> Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
> Assisted-by: Claude:claude-4.6-opus
> ---
>  drivers/iommu/intel/dmar.c | 33 +++++++++++++++++++++------------
>  1 file changed, 21 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
> index d33c119a935e..225fa498d714 100644
> --- a/drivers/iommu/intel/dmar.c
> +++ b/drivers/iommu/intel/dmar.c
> @@ -1890,30 +1890,39 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
>  {
>  	const char *reason;
>  	int fault_type;
> +	u8 bus = source_id >> 8;
> +	u8 devfn = source_id & 0xFF;
> +	struct pci_dev *pdev;
> +	char devid[48];

Why not have a #define for this like you have for AMD and Arm?

>  
>  	reason = dmar_get_fault_reason(fault_reason, &fault_type);
>  
> +	pdev = pci_get_domain_bus_and_slot(iommu->segment, bus, devfn);

Not an Intel iommu expert, but I have concerns about using 
pci_get_domain_bus_and_slot() in this path.

AFAICT, dmar_fault_do_one() is running in a IRQ context & the pci_get_* 
family of functions iterates the global PCI klist. It eventually calls
bus_to_subsys(), which takes a plain spin_lock(&bus_kset->list_lock) [1]
which isn't IRQ-safe. Same thing with klist_put [2] called in klist_iter_exit

> +	if (pdev) {
> +		snprintf(devid, sizeof(devid), "%04x:%02x:%02x.%d %04x:%04x",
> +			 iommu->segment, bus, PCI_SLOT(devfn), PCI_FUNC(devfn),
> +			 pdev->vendor, pdev->device);
> +		pci_dev_put(pdev);

Same here, pci_dev_put call put_device which might sleep [3] and hence
shouldn't be called in hard IRQ context.

> +	} else {
> +		snprintf(devid, sizeof(devid), "%04x:%02x:%02x.%d",
> +			 iommu->segment, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
> +	}
> +
>  	if (fault_type == INTR_REMAP) {
> -		pr_err("[INTR-REMAP] Request device [%02x:%02x.%d] fault index 0x%llx [fault reason 0x%02x] %s\n",
> -		       source_id >> 8, PCI_SLOT(source_id & 0xFF),
> -		       PCI_FUNC(source_id & 0xFF), addr >> 48,
> -		       fault_reason, reason);
> +		pr_err("[INTR-REMAP] Request device [%s] fault index 0x%llx [fault reason 0x%02x] %s\n",
> +		       devid, addr >> 48, fault_reason, reason);
>  
>  		return 0;
>  	}
>  

[-------------- >8 -------------------]

Thanks,
Praan

[1] https://elixir.bootlin.com/linux/v7.0.1/source/drivers/base/bus.c#L60
[2] https://elixir.bootlin.com/linux/v7.0.1/source/lib/klist.c#L209
[3] https://elixir.bootlin.com/linux/v7.0.1/source/drivers/base/core.c#L3794

Re: [PATCH 3/3] iommu/amd: Add vendor:device ID to AMD IOMMU event logs

[Pranjal Shrivastava]

On Wed, May 06, 2026 at 03:05:39PM +0000, Yigit Oguz wrote:
> Add amd_iommu_devid_str() helper that formats PCI device identity as
> SSSS:BB:DD.F VVVV:DDDD by looking up the pci_dev via
> pci_get_domain_bus_and_slot. Falls back to SSSS:BB:DD.F when the
> device is not found.
> 
> Before:
>   AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 domain=0x000a
>   	address=0xe0000000 flags=0x0020]
> 
> After:
>   AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 8086:1533 domain=0x000a
>   	address=0xe0000000 flags=0x0020]
> 
> Signed-off-by: Yigit Oguz <yigitogu@amazon.de>
> Signed-off-by: Lilit Janpoladyan <lilitj@amazon.com>
> Assisted-by: Claude:claude-4.6-opus
> ---
>  drivers/iommu/amd/iommu.c | 94 ++++++++++++++++++++++++---------------
>  1 file changed, 58 insertions(+), 36 deletions(-)
> 
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index 01171361f9bc..441b4a7e85d5 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -779,11 +779,34 @@ static void dump_command(unsigned long phys_addr)
>  		pr_err("CMD[%d]: %08x\n", i, cmd->data[i]);
>  }
>  
> +#define AMD_IOMMU_DEVID_SIZE	48
> +
> +static void amd_iommu_devid_str(struct amd_iommu *iommu, u16 devid, char *buf,
> +				size_t size)
> +{
> +	struct pci_dev *pdev;
> +
> +	pdev = pci_get_domain_bus_and_slot(iommu->pci_seg->id,
> +					   PCI_BUS_NUM(devid), devid & 0xff);
> +	if (pdev) {
> +		snprintf(buf, size, "%04x:%02x:%02x.%x %04x:%04x",
> +			 iommu->pci_seg->id, PCI_BUS_NUM(devid),
> +			 PCI_SLOT(devid), PCI_FUNC(devid),
> +			 pdev->vendor, pdev->device);
> +		pci_dev_put(pdev);

From a quick glance it looks like we call this in bottom halves, which
looks fine.

> +	} else {
> +		snprintf(buf, size, "%04x:%02x:%02x.%x",
> +			 iommu->pci_seg->id, PCI_BUS_NUM(devid),
> +			 PCI_SLOT(devid), PCI_FUNC(devid));
> +	}
> +}
> +
>  static void amd_iommu_report_rmp_hw_error(struct amd_iommu *iommu, volatile u32 *event)
>  {
>  	struct iommu_dev_data *dev_data = NULL;
>  	int devid, vmg_tag, flags;
>  	struct pci_dev *pdev;
> +	char devid_str[AMD_IOMMU_DEVID_SIZE];
>  	u64 spa;
>  
>  	devid   = (event[0] >> EVENT_DEVID_SHIFT) & EVENT_DEVID_MASK;
> @@ -796,15 +819,16 @@ static void amd_iommu_report_rmp_hw_error(struct amd_iommu *iommu, volatile u32
>  	if (pdev)
>  		dev_data = dev_iommu_priv_get(&pdev->dev);
>  
> +	amd_iommu_devid_str(iommu, devid, devid_str, sizeof(devid_str));

Will this iterate the global pci dev list for EVERY event? I'm wondering
if we could improve that somehow?

[------------- >8 ---------------]

Thanks,
Praan

Re: [PATCH 0/3] iommu: Add PCI vendor:device ID to IOMMU fault logs

[Robin Murphy]

On 2026-05-06 4:05 pm, Yigit Oguz wrote:
> IOMMU fault and event logs currently identify devices using only their
> PCI segment/bus/device/function (SSSS:BB:DD.F). While mapping a single
> BDF to a device type is straightforward, doing so at scale across many
> hosts and thousands of fault events requires additional tooling and
> manual cross-referencing. Including the vendor:device ID directly in
> the log line makes each event self-contained and immediately actionable
> without any post-processing.

Sorry, but why are unexpected DMA faults happening "at scale" in the 
first place? If you have so many broken drivers that disambiguating them 
needs help from the kernel, something seems fundamentally wrong with 
that picture. Conversely if these are devices assigned to userspace then 
we should perhaps reconsider their ability to spam up the host kernel 
log at will anyway.

I'm not saying I necessarily have anything against this change in 
particular, but it has a strong smell of effort being spent on the wrong 
thing...

(And even then AFAICS it only really helps in the specific scenario of 
having only one of each type of device, otherwise you're back to still 
needing per-system knowledge of how BDFs map to physical instances to 
know what's what.)

Thanks,
Robin.

> This series adds vendor:device ID (VVVV:DDDD) to IOMMU event logs for
> ARM SMMUv3, Intel VT-d and AMD IOMMU.
> 
> Before:
>    arm-smmu-v3 arm-smmu-v3.0.auto: event: F_TRANSLATION client: 0000:2b:11.6
>      sid: 0x158e ssid: 0x0 iova: 0x280000000000 ipa: 0x0
>    DMAR: [DMA Write NO_PASID] Request device [86:00.0] fault addr 0xe0000000
>      [fault reason 0x05] PTE Write access is not set
>    AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 domain=0x000a
>      address=0xe0000000 flags=0x0020]
> 
> After:
>    arm-smmu-v3 arm-smmu-v3.0.auto: event: F_TRANSLATION client: 0000:2b:11.6 [8086:1533]
>      sid: 0x158e ssid: 0x0 iova: 0x280000000000 ipa: 0x0
>    DMAR: [DMA Write NO_PASID] Request device [0000:86:00.0 8086:1533] fault addr 0xe0000000
>      [fault reason 0x05] PTE Write access is not set
>    AMD-Vi: Event logged [IO_PAGE_FAULT device=0000:41:00.0 8086:1533 domain=0x000a
>      address=0xe0000000 flags=0x0020]
> 
> Patch 1 adds vendor:device ID to ARM SMMUv3 translation fault logs.
> Patch 2 adds PCI segment and vendor:device ID to Intel VT-d DMAR
>          fault logs.
> Patch 3 adds a devid_str helper and vendor:device ID to all AMD IOMMU
>          event log paths.
> 
> Testing:
> Build-tested against mainline Linux (torvalds/master).
> 
> Runtime-tested on a custom downstream branch on ARM SMMUv3, Intel VT-d and
> AMD IOMMU hosts. Translation faults were induced in a virtualized setup
> by removing DMA mappings for an in-use region, causing the assigned device's
> subsequent DMA transactions to hit unmapped IOVAs and produce
> translation fault events. The resulting log lines were verified to
> contain the PCI vendor:device ID on all three platforms.
> 
> Lilit Janpoladyan (1):
>    iommu/arm-smmu-v3: Print PCI vendor:device ID in SMMU translation
>      fault logs
> 
> Yigit Oguz (2):
>    iommu/vt-d: Add PCI segment and vendor:device ID to DMAR fault logs
>    iommu/amd: Add vendor:device ID to AMD IOMMU event logs
> 
>   drivers/iommu/amd/iommu.c                   | 94 +++++++++++++--------
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 ++++++-
>   drivers/iommu/intel/dmar.c                  | 33 +++++---
>   3 files changed, 104 insertions(+), 52 deletions(-)
>