[PATCH v3 6/7] iommu/vt-d: Warn on out-of-range invalidation address

From: Jacob Pan
Date: Wed Jul 01 2020 - 11:27:37 EST


For guest requested IOTLB invalidation, address and mask are provided as
part of the invalidation data. VT-d HW silently ignores any address bits
below the mask. SW shall also allow such case but give warning if
address does not align with the mask. This patch relax the fault
handling from error to warning and proceed with invalidation request
with the given mask.

Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 6a0c62c7395c..2e1b53ade784 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5439,13 +5439,12 @@ intel_iommu_sva_invalidate(struct iommu_domain *domain, struct device *dev,

switch (BIT(cache_type)) {
case IOMMU_CACHE_INV_TYPE_IOTLB:
+ /* HW will ignore LSB bits based on address mask */
if (inv_info->granularity == IOMMU_INV_GRANU_ADDR &&
size &&
(inv_info->addr_info.addr & ((BIT(VTD_PAGE_SHIFT + size)) - 1))) {
- pr_err_ratelimited("Address out of range, 0x%llx, size order %llu\n",
- inv_info->addr_info.addr, size);
- ret = -ERANGE;
- goto out_unlock;
+ pr_err_ratelimited("User address not aligned, 0x%llx, size order %llu\n",
+ inv_info->addr_info.addr, size);
}

/*
--
2.7.4