iommu/vt-d: Do not wipe out the page table NID when devices detach

The NID is used to control which NUMA node memory for the page table is
allocated it from. It should be a permanent property of the page table
when it was allocated and not change during attach/detach of devices.

Reviewed-by: Wei Wang <[email protected]>
Reviewed-by: Kevin Tian <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lu Baolu <[email protected]>
Fixes: 7c20442 ("iommu/vt-d: Add domain_alloc_paging support")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

Author: jgunthorpe

drivers/iommu/intel/iommu.c

@@ -1391,7 +1391,6 @@ void domain_detach_iommu(struct dmar_domain *domain, struct intel_iommu *iommu)
 	if (--info->refcnt == 0) {
 		ida_free(&iommu->domain_ida, info->did);
 		xa_erase(&domain->iommu_array, iommu->seq_id);
-		domain->nid = NUMA_NO_NODE;
 		kfree(info);
 	}
 }