intel-iommu: Warn about unmatched unmap requests
This would have found the bug in i386 pci_unmap_addr() a long time ago.
We shouldn't just silently return without doing anything.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 02223e2..2bbc3fc 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -2640,7 +2640,8 @@
iommu = domain_get_iommu(domain);
iova = find_iova(&domain->iovad, IOVA_PFN(dev_addr));
- if (!iova)
+ if (WARN_ONCE(!iova, "Driver unmaps unmatched page at PFN %llx\n",
+ (unsigned long long)dev_addr))
return;
start_pfn = mm_to_dma_pfn(iova->pfn_lo);
@@ -2730,7 +2731,8 @@
iommu = domain_get_iommu(domain);
iova = find_iova(&domain->iovad, IOVA_PFN(sglist[0].dma_address));
- if (!iova)
+ if (WARN_ONCE(!iova, "Driver unmaps unmatched sglist at PFN %llx\n",
+ (unsigned long long)sglist[0].dma_address))
return;
start_pfn = mm_to_dma_pfn(iova->pfn_lo);