iommu/amd: Fix a stale comment about which legacy mode is user visible

Update a stale comment about which of the legacy modes is visible to the
user, i.e. can be forced via amd_iommu_intr=legacy.

Fixes: b74aa02d7a30 ("iommu/amd: Fix legacy interrupt remapping for x2APIC-enabled system")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Wei Wang <wei.w.wang@hotmail.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index f9f7180878930341e92a42b318cb61de6d569637..c726d115939a6ba8ad1cd9aac3e13f5d09fd439a 100644 (file)
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -948,12 +948,13 @@ static inline int get_hpet_devid(int id)
 }
 
 enum amd_iommu_intr_mode_type {
-       AMD_IOMMU_GUEST_IR_LEGACY,
-
-       /* This mode is not visible to users. It is used when
-        * we cannot fully enable vAPIC and fallback to only support
-        * legacy interrupt remapping via 128-bit IRTE.
+       /*
+        * The legacy format mode is not visible to users to prevent the user
+        * from crashing x2APIC systems, which for all intents and purposes
+        * require 128-bit IRTEs.   The legacy format will be forced as needed
+        * when hardware doesn't support 128-bit IRTEs.
         */
+       AMD_IOMMU_GUEST_IR_LEGACY,
        AMD_IOMMU_GUEST_IR_LEGACY_GA,
        AMD_IOMMU_GUEST_IR_VAPIC,
 };