[PATCH v2 13/17] iommu/vt-d: Remove BUG_ON in handling iotlb cache invalidation

From: Lu Baolu
Date: Thu Apr 13 2023 - 00:08:30 EST


From: Tina Zhang <tina.zhang@xxxxxxxxx>

VT-d iotlb cache invalidation request with unexpected type is considered
as a bug to developers, which can be fixed. So, when such kind of issue
comes out, it needs to be reported through the kernel log, instead of
halting the system. Replacing BUG_ON with warning reporting.

Signed-off-by: Tina Zhang <tina.zhang@xxxxxxxxx>
Link: https://lore.kernel.org/r/20230406065944.2773296-4-tina.zhang@xxxxxxxxx
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index c4847a5aaf52..dd61bb554aa7 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1272,7 +1272,9 @@ static void __iommu_flush_context(struct intel_iommu *iommu,
| DMA_CCMD_SID(source_id) | DMA_CCMD_FM(function_mask);
break;
default:
- BUG();
+ pr_warn("%s: Unexpected context-cache invalidation type 0x%llx\n",
+ iommu->name, type);
+ return;
}
val |= DMA_CCMD_ICC;

@@ -1308,7 +1310,9 @@ static void __iommu_flush_iotlb(struct intel_iommu *iommu, u16 did,
val_iva = size_order | addr;
break;
default:
- BUG();
+ pr_warn("%s: Unexpected iotlb invalidation type 0x%llx\n",
+ iommu->name, type);
+ return;
}
/* Note: set drain read/write */
#if 0
@@ -1483,7 +1487,8 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
uint64_t addr = (uint64_t)pfn << VTD_PAGE_SHIFT;
u16 did = domain_id_iommu(domain, iommu);

- BUG_ON(pages == 0);
+ if (WARN_ON(!pages))
+ return;

if (ih)
ih = 1 << 6;
--
2.34.1