CVE-2026-64152

In the Linux kernel, the following vulnerability has been resolved:

iommu: Handle unmap error when iommu_debug is enabled

Sashiko noticed a latent bug where the map error flow called iommu_unmap()

which calls iommu_debug_unmap_begin()/iommu_debug_unmap_end() however

since this is an error path the map flow never actually established the

original iommu_debug_map() it will malfunction.

Lift the unmap error handling into iommu_map_nosync() and reorder it so

the trace_map()/iommu_debug_map() records the partial mapping and then

immediately unmaps it. This avoid creating the unbalanced tracking and

provides saner tracing instead of a unmap unmatched to any map.