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

From: Yigit Oguz

Date: Wed May 06 2026 - 11:08:29 EST


From: Lilit Janpoladyan <lilitj@xxxxxxxxxx>

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@xxxxxxxxxx>
Signed-off-by: Yigit Oguz <yigitogu@xxxxxxxxx>
---
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




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