iommu: minor fixes

Signed-off-by: Cheng Li <cheng.li10@unsw.edu.au>

Author: Cheng-Li1

build_sdk.py

@@ -67,7 +67,6 @@
 DEFAULT_KERNEL_OPTIONS_X86_64 = {
     "KernelPlatform": "pc99",
     "KernelX86MicroArch": "generic",
-    # See https://github.com/seL4/microkit/issues/418 for details.
     "KernelIOMMU": True,
 } | DEFAULT_KERNEL_OPTIONS
 

tool/microkit/src/capdl/iomem.rs

@@ -13,7 +13,7 @@ use crate::{
     sel4::Config,
 };
 
-// Logic of seL4 setting VT-d page table level: 
+// Logic of seL4 setting VT-d page table level:
 // Determine whether three-level VT-d pt is supported by host. If supported, set PT level to three if supported.
 // If not, check whether 4, 5, 6, 2 level is supported one by one.
 // https://github.com/seL4/seL4/blob/15.0.0/src/plat/pc99/machine/intel-vtd.c#L498
@@ -48,7 +48,7 @@ pub fn create_iospace(
         }),
     });
 
-    // Domain ID cannot be negative so add one to PD ID
+    // Domain ID cannot be zero so add one to PD ID
     const PD_TO_DOMAIN_ID_OFFSET: u16 = 1;
 
     spec_container.add_root_object(CapDLNamedObject {

tool/microkit/src/sdf.rs

@@ -1775,7 +1775,7 @@ fn io_check_maps(
                 if map_end > crate::capdl::iomem::VTD_MAX_ADDR {
                     return Err(
                         format!(
-                            "Error: iomap for '{}' has address 0x{:x} which exceeds the upper limits of 0x{:x} in {} '{}' @ {}",
+                            "Error: iomap for '{}' has address {:#x} which exceeds the upper limits of {:#x} in {} '{}' @ {}",
                             io_map.name,
                             map_end,
                             crate::capdl::iomem::VTD_MAX_ADDR,

tool/microkit/tests/sdf/iommu_out_of_bound.system

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
- Copyright 2024, UNSW.
+ Copyright 2026, UNSW.
 
  SPDX-License-Identifier: BSD-2-Clause
 -->

tool/microkit/tests/test.rs

@@ -697,11 +697,11 @@ mod protection_domain {
     }
 
     #[test]
-    fn test_iommu_valid_on_x86() {
+    fn test_iommu_out_of_bound() {
         check_error(
             &DEFAULT_X86_64_KERNEL_CONFIG,
             "iommu_out_of_bound.system",
-            "Error: iomap for 'region' has address 0x8000001000 which exceeds the upper limits of 549755813887 in protection domain 'test' @ iommu_out_of_bound.system:13:9",
+            "Error: iomap for 'region' has address 0x8000001000 which exceeds the upper limits of 0x7FFFFFFFFF in protection domain 'test' @ iommu_out_of_bound.system:13:9",
         )
     }
 }