[RFC v16 8/9] iommu/smmuv3: report additional recoverable faults

Eric Auger
2021-10-27T10:46:51Z

Up to now we have only reported translation faults. Now that
the guest can induce some configuration faults, let's report them
too. Add propagation for BAD_SUBSTREAMID, CD_FETCH, BAD_CD, WALK_EABT.
We also fix the transcoding for some existing translation faults.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v14 -> v15:
- adapt to removal of IOMMU_FAULT_UNRECOV_FETCH_ADDR_VALID
in [PATCH v13 10/10] iommu/arm-smmu-v3: Add stall support for
platform devices
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 40 +++++++++++++++++++--
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 4 +++
2 files changed, 42 insertions(+), 2 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 e84a7c3e8730..ddfc069c10ae 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1488,6 +1488,7 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
u32 perm = 0;
struct arm_smmu_master *master;
bool ssid_valid = evt[0] & EVTQ_0_SSV;
+ u8 type = FIELD_GET(EVTQ_0_ID, evt[0]);
u32 sid = FIELD_GET(EVTQ_0_SID, evt[0]);
struct iommu_fault_event fault_evt = { };
struct iommu_fault *flt = &fault_evt.fault;
@@ -1540,8 +1541,6 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
} else {
flt->type = IOMMU_FAULT_DMA_UNRECOV;
flt->event = (struct iommu_fault_unrecoverable) {
- .reason = reason,
- .flags = IOMMU_FAULT_UNRECOV_ADDR_VALID,
.perm = perm,
.addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
};
@@ -1550,6 +1549,43 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
flt->event.flags |= IOMMU_FAULT_UNRECOV_PASID_VALID;
flt->event.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
}
+
+ switch (type) {
+ case EVT_ID_TRANSLATION_FAULT:
+ flt->event.reason = IOMMU_FAULT_REASON_PTE_FETCH;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_ADDR_VALID;
+ break;
+ case EVT_ID_ADDR_SIZE_FAULT:
+ flt->event.reason = IOMMU_FAULT_REASON_OOR_ADDRESS;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_ADDR_VALID;
+ break;
+ case EVT_ID_ACCESS_FAULT:
+ flt->event.reason = IOMMU_FAULT_REASON_ACCESS;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_ADDR_VALID;
+ break;
+ case EVT_ID_PERMISSION_FAULT:
+ flt->event.reason = IOMMU_FAULT_REASON_PERMISSION;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_ADDR_VALID;
+ break;
+ case EVT_ID_BAD_SUBSTREAMID:
+ flt->event.reason = IOMMU_FAULT_REASON_PASID_INVALID;
+ break;
+ case EVT_ID_CD_FETCH:
+ flt->event.reason = IOMMU_FAULT_REASON_PASID_FETCH;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_FETCH_ADDR_VALID;
+ break;
+ case EVT_ID_BAD_CD:
+ flt->event.reason = IOMMU_FAULT_REASON_BAD_PASID_ENTRY;
+ break;
+ case EVT_ID_WALK_EABT:
+ flt->event.reason = IOMMU_FAULT_REASON_WALK_EABT;
+ flt->event.flags |= IOMMU_FAULT_UNRECOV_ADDR_VALID |
+ IOMMU_FAULT_UNRECOV_FETCH_ADDR_VALID;
+ break;
+ default:
+ /* TODO: report other unrecoverable faults. */
+ return -EFAULT;
+ }
}

mutex_lock(&smmu->streams_mutex);
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 05959df01618..b914570ee5ba 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -379,6 +379,10 @@

#define EVTQ_0_ID GENMASK_ULL(7, 0)

+#define EVT_ID_BAD_SUBSTREAMID 0x08
+#define EVT_ID_CD_FETCH 0x09
+#define EVT_ID_BAD_CD 0x0a
+#define EVT_ID_WALK_EABT 0x0b
#define EVT_ID_TRANSLATION_FAULT 0x10
#define EVT_ID_ADDR_SIZE_FAULT 0x11
#define EVT_ID_ACCESS_FAULT 0x12
--
2.26.3