iommu/vt-d: Always reserve a domain ID for identity setup

We will use a global static identity domain. Reserve a static domain ID
for it.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Link: https://lore.kernel.org/r/20240809055431.36513-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 723ea9f3f501af9032ea34782736fa602a427e10..c019fb3b3e783fb3fc02df360366c9ff916d7663 100644 (file)
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1440,10 +1440,10 @@ static int iommu_init_domains(struct intel_iommu *iommu)
         * entry for first-level or pass-through translation modes should
         * be programmed with a domain id different from those used for
         * second-level or nested translation. We reserve a domain id for
-        * this purpose.
+        * this purpose. This domain id is also used for identity domain
+        * in legacy mode.
         */
-       if (sm_supported(iommu))
-               set_bit(FLPT_DEFAULT_DID, iommu->domain_ids);
+       set_bit(FLPT_DEFAULT_DID, iommu->domain_ids);
 
        return 0;
 }