iommu/vt-d: Tweak the description of a DMA fault

The Intel IOMMU driver reports the DMA fault reason in a decimal number
while the VT-d specification uses a hexadecimal one. It's inconvenient
that users need to covert them everytime before consulting the spec.
Let's use hexadecimal number for a DMA fault reason.

The fault message uses 0xffffffff as PASID for DMA requests w/o PASID.
This is confusing. Tweak this by adding "NO_PASID" explicitly.

Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210517065425.4953-1-baolu.lu@linux.intel.com
Link: https://lore.kernel.org/r/20210610020115.1637656-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/dmar.c

@@ -1913,16 +1913,23 @@ static int dmar_fault_do_one(struct intel_iommu *iommu, int type,
 	reason = dmar_get_fault_reason(fault_reason, &fault_type);
 
 	if (fault_type == INTR_REMAP)
-		pr_err("[INTR-REMAP] Request device [%02x:%02x.%d] fault index %llx [fault reason %02d] %s\n",
-			source_id >> 8, PCI_SLOT(source_id & 0xFF),
-			PCI_FUNC(source_id & 0xFF), addr >> 48,
-			fault_reason, reason);
-	else
-		pr_err("[%s] Request device [%02x:%02x.%d] PASID %x fault addr %llx [fault reason %02d] %s\n",
+		pr_err("[INTR-REMAP] Request device [0x%02x:0x%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);
+	else if (pasid == INVALID_IOASID)
+		pr_err("[%s NO_PASID] Request device [0x%02x:0x%02x.%d] 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), pasid, addr,
+		       PCI_FUNC(source_id & 0xFF), addr,
 		       fault_reason, reason);
+	else
+		pr_err("[%s PASID 0x%x] Request device [0x%02x:0x%02x.%d] 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);
+
 	return 0;
 }
 
@@ -1989,7 +1996,7 @@ irqreturn_t dmar_fault(int irq, void *dev_id)
 		if (!ratelimited)
 			/* Using pasid -1 if pasid is not present */
 			dmar_fault_do_one(iommu, type, fault_reason,
-					  pasid_present ? pasid : -1,
+					  pasid_present ? pasid : INVALID_IOASID,
 					  source_id, guest_addr);
 
 		fault_index++;