diff mbox series

[v7,02/12] iommu/arm-smmu-v3: Remove unrecoverable faults reporting

Message ID 20231115030226.16700-3-baolu.lu@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series iommu: Prepare to deliver page faults to user space | expand

Commit Message

Baolu Lu Nov. 15, 2023, 3:02 a.m. UTC 
No device driver registers fault handler to handle the reported
unrecoveraable faults. Remove it to avoid dead code.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 46 ++++++---------------
 1 file changed, 13 insertions(+), 33 deletions(-)

Comments

Jason Gunthorpe Dec. 1, 2023, 3:42 p.m. UTC | #1 
On Wed, Nov 15, 2023 at 11:02:16AM +0800, Lu Baolu wrote:
> No device driver registers fault handler to handle the reported
> unrecoveraable faults. Remove it to avoid dead code.
> 
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
>  drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 46 ++++++---------------
>  1 file changed, 13 insertions(+), 33 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>

If we do bring this back it will be in some form where the opaque
driver event information is delivered to userspace to forward to the
VM.

Jason
Liu, Yi L Dec. 4, 2023, 10:54 a.m. UTC | #2 
On 2023/11/15 11:02, Lu Baolu wrote:
> No device driver registers fault handler to handle the reported
> unrecoveraable faults. Remove it to avoid dead code.

I noticed only ARM code is removed. So intel iommu driver does not have
code that tries to report unrecoveraable faults?

> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> ---
>   drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 46 ++++++---------------
>   1 file changed, 13 insertions(+), 33 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 7445454c2af2..505400538a2e 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -1463,7 +1463,6 @@ arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
>   static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>   {
>   	int ret;
> -	u32 reason;
>   	u32 perm = 0;
>   	struct arm_smmu_master *master;
>   	bool ssid_valid = evt[0] & EVTQ_0_SSV;
> @@ -1473,16 +1472,9 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>   
>   	switch (FIELD_GET(EVTQ_0_ID, evt[0])) {
>   	case EVT_ID_TRANSLATION_FAULT:
> -		reason = IOMMU_FAULT_REASON_PTE_FETCH;
> -		break;
>   	case EVT_ID_ADDR_SIZE_FAULT:
> -		reason = IOMMU_FAULT_REASON_OOR_ADDRESS;
> -		break;
>   	case EVT_ID_ACCESS_FAULT:
> -		reason = IOMMU_FAULT_REASON_ACCESS;
> -		break;
>   	case EVT_ID_PERMISSION_FAULT:
> -		reason = IOMMU_FAULT_REASON_PERMISSION;
>   		break;
>   	default:
>   		return -EOPNOTSUPP;
> @@ -1492,6 +1484,9 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>   	if (evt[1] & EVTQ_1_S2)
>   		return -EFAULT;
>   
> +	if (!(evt[1] & EVTQ_1_STALL))
> +		return -EOPNOTSUPP;
> +
>   	if (evt[1] & EVTQ_1_RnW)
>   		perm |= IOMMU_FAULT_PERM_READ;
>   	else
> @@ -1503,32 +1498,17 @@ static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
>   	if (evt[1] & EVTQ_1_PnU)
>   		perm |= IOMMU_FAULT_PERM_PRIV;
>   
> -	if (evt[1] & EVTQ_1_STALL) {
> -		flt->type = IOMMU_FAULT_PAGE_REQ;
> -		flt->prm = (struct iommu_fault_page_request) {
> -			.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
> -			.grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
> -			.perm = perm,
> -			.addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
> -		};
> +	flt->type = IOMMU_FAULT_PAGE_REQ;
> +	flt->prm = (struct iommu_fault_page_request) {
> +		.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
> +		.grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
> +		.perm = perm,
> +		.addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
> +	};
>   
> -		if (ssid_valid) {
> -			flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
> -			flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
> -		}
> -	} 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]),
> -		};
> -
> -		if (ssid_valid) {
> -			flt->event.flags |= IOMMU_FAULT_UNRECOV_PASID_VALID;
> -			flt->event.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
> -		}
> +	if (ssid_valid) {
> +		flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
> +		flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
>   	}
>   
>   	mutex_lock(&smmu->streams_mutex);
Baolu Lu Dec. 5, 2023, 11:48 a.m. UTC | #3 
On 2023/12/4 18:54, Yi Liu wrote:
> On 2023/11/15 11:02, Lu Baolu wrote:
>> No device driver registers fault handler to handle the reported
>> unrecoveraable faults. Remove it to avoid dead code.
> 
> I noticed only ARM code is removed. So intel iommu driver does not have
> code that tries to report unrecoveraable faults?

Yes.

Best regards,
baolu
diff mbox series

Patch

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 7445454c2af2..505400538a2e 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1463,7 +1463,6 @@  arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
 static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
 {
 	int ret;
-	u32 reason;
 	u32 perm = 0;
 	struct arm_smmu_master *master;
 	bool ssid_valid = evt[0] & EVTQ_0_SSV;
@@ -1473,16 +1472,9 @@  static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
 
 	switch (FIELD_GET(EVTQ_0_ID, evt[0])) {
 	case EVT_ID_TRANSLATION_FAULT:
-		reason = IOMMU_FAULT_REASON_PTE_FETCH;
-		break;
 	case EVT_ID_ADDR_SIZE_FAULT:
-		reason = IOMMU_FAULT_REASON_OOR_ADDRESS;
-		break;
 	case EVT_ID_ACCESS_FAULT:
-		reason = IOMMU_FAULT_REASON_ACCESS;
-		break;
 	case EVT_ID_PERMISSION_FAULT:
-		reason = IOMMU_FAULT_REASON_PERMISSION;
 		break;
 	default:
 		return -EOPNOTSUPP;
@@ -1492,6 +1484,9 @@  static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
 	if (evt[1] & EVTQ_1_S2)
 		return -EFAULT;
 
+	if (!(evt[1] & EVTQ_1_STALL))
+		return -EOPNOTSUPP;
+
 	if (evt[1] & EVTQ_1_RnW)
 		perm |= IOMMU_FAULT_PERM_READ;
 	else
@@ -1503,32 +1498,17 @@  static int arm_smmu_handle_evt(struct arm_smmu_device *smmu, u64 *evt)
 	if (evt[1] & EVTQ_1_PnU)
 		perm |= IOMMU_FAULT_PERM_PRIV;
 
-	if (evt[1] & EVTQ_1_STALL) {
-		flt->type = IOMMU_FAULT_PAGE_REQ;
-		flt->prm = (struct iommu_fault_page_request) {
-			.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
-			.grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
-			.perm = perm,
-			.addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
-		};
+	flt->type = IOMMU_FAULT_PAGE_REQ;
+	flt->prm = (struct iommu_fault_page_request) {
+		.flags = IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE,
+		.grpid = FIELD_GET(EVTQ_1_STAG, evt[1]),
+		.perm = perm,
+		.addr = FIELD_GET(EVTQ_2_ADDR, evt[2]),
+	};
 
-		if (ssid_valid) {
-			flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
-			flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
-		}
-	} 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]),
-		};
-
-		if (ssid_valid) {
-			flt->event.flags |= IOMMU_FAULT_UNRECOV_PASID_VALID;
-			flt->event.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
-		}
+	if (ssid_valid) {
+		flt->prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+		flt->prm.pasid = FIELD_GET(EVTQ_0_SSID, evt[0]);
 	}
 
 	mutex_lock(&smmu->streams_mutex);